From VM Tue Jan 2 13:33:18 2001 X-VM-Summary-Format: "%n %*%a %-17.17F %-3.3m %2d %4l/%-5c %I\"%s\"\n" X-VM-Labels: nil X-VM-VHeader: ("Resent-" "From:" "Sender:" "To:" "Apparently-To:" "Cc:" "Subject:" "Date:") nil X-VM-Last-Modified: (15015 61160 151879) X-VM-IMAP-Retrieved: nil X-VM-POP-Retrieved: nil X-VM-Bookmark: 1 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1058" "Tuesday" "2" "January" "2001" "16:23:02" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "26" "starship-design: Going Up? Space Elevator: Next Stop, Earth Orbit" "^From:" nil nil "1" nil nil nil nil nil] nil) Content-Length: 1058 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f02LNIO20819 for starship-design-outgoing; Tue, 2 Jan 2001 13:23:18 -0800 (PST) Received: from imo-r01.mx.aol.com (imo-r01.mx.aol.com [152.163.225.1]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f02LNHm20813 for ; Tue, 2 Jan 2001 13:23:17 -0800 (PST) Received: from KellySt@aol.com by imo-r01.mx.aol.com (mail_out_v28.35.) id n.d6.7b06e4 (4198); Tue, 2 Jan 2001 16:23:02 -0500 (EST) Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: DTaylor648@aol.com, JohnFrance@aol.com, moschleg@erols.com, SFnoirSD@aol.com, starship-design@lists.uoregon.edu, DotarSojat@aol.com, rddesign@rddesigns.com, RICKJ@btio.com Subject: starship-design: Going Up? Space Elevator: Next Stop, Earth Orbit Date: Tue, 2 Jan 2001 16:23:02 EST http://www.space.com/businesstechnology/technology/space_elevator_001226.html Interesting short article on nanotube based skyhooks, which are now considered more nearterm then I would have expected. Kelly ========================================================== Bradley Edwards, a physicist at Los Alamos National Laboratories in New Mexico, is a keen supporter of fabricating an elevator to space. He recently completed research on lengthy space elevators thanks to a NASA Institute for Advanced Concepts grant. "The space elevator appears much closer to reality than has been suspected in terms of available technology, cost and schedule," Edwards said. "The major hurdle is the required carbon nanotubes, but that's getting closer each day," he said. Edwards has scripted a plan that suggests an operational cable to space can be installed within 10 to 20 years. From VM Tue Jan 2 17:55:51 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1803" "Tuesday" "2" "January" "2001" "17:36:30" "-0800" "N. Lindberg" "nlindber@u.washington.edu" nil "46" "Re: starship-design: Going Up? Space Elevator: Next Stop, Earth Orbit" "^From:" nil nil "1" nil nil nil nil nil] nil) Content-Length: 1803 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f031aXp07436 for starship-design-outgoing; Tue, 2 Jan 2001 17:36:33 -0800 (PST) Received: from jason04.u.washington.edu (root@jason04.u.washington.edu [140.142.8.53]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f031aVm07429 for ; Tue, 2 Jan 2001 17:36:31 -0800 (PST) Received: from dante36.u.washington.edu (nlindber@dante36.u.washington.edu [140.142.15.196]) by jason04.u.washington.edu (8.9.3+UW00.05/8.9.3+UW00.12) with ESMTP id RAA23996; Tue, 2 Jan 2001 17:36:31 -0800 Received: from localhost (nlindber@localhost) by dante36.u.washington.edu (8.9.3+UW00.05/8.9.3+UW00.12) with ESMTP id RAA55776; Tue, 2 Jan 2001 17:36:30 -0800 In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Precedence: bulk Reply-To: "N. Lindberg" From: "N. Lindberg" Sender: owner-starship-design@lists.uoregon.edu To: KellySt@aol.com cc: starship design Subject: Re: starship-design: Going Up? Space Elevator: Next Stop, Earth Orbit Date: Tue, 2 Jan 2001 17:36:30 -0800 (PST) Neat article. It seems like the nanotubes are the thing. A question though. Since nanotubes are (as i recall) electricly conductive, do you think it likely that friction with the atmosphere at lowerlevels, and photoelectric charging in space would tend to induce currents in the cable? It seems reasonable to me that the potential between one part of the cable and another could be quite high. Comments? Nels _____________________________________________ Nobody's perfect, but we are working on it. -Manfred Freiherr von Richthofen When you come to a fork in the road, take it. -Yogi Berra _____________________________________________ On Tue, 2 Jan 2001 KellySt@aol.com wrote: > > http://www.space.com/businesstechnology/technology/space_elevator_001226.html > > Interesting short article on nanotube based skyhooks, which are now > considered more nearterm then I would have expected. > > Kelly > > > > ========================================================== > Bradley Edwards, a physicist at Los Alamos National > Laboratories in New Mexico, is a keen supporter of > fabricating > an elevator to space. He recently completed research on > lengthy space elevators thanks to a NASA Institute for > Advanced Concepts grant. > > "The space elevator appears much closer to reality than has > been suspected in terms of available technology, cost and > schedule," Edwards said. "The major hurdle is the required > carbon nanotubes, but that's getting closer each day," he > said. > > Edwards has scripted a plan that suggests an operational > cable to space can be installed within 10 to 20 years. > From VM Wed Jan 3 10:10:07 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2337" "Tuesday" "2" "January" "2001" "22:05:28" "-0500" "Curtis Manges" "curtismanges@netscape.net" nil "64" "[Fwd: Re: starship-design: Going Up? Space Elevator: Next Stop, EarthOrbit]" "^From:" nil nil "1" nil nil nil nil nil] nil) Content-Length: 2337 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f0335a005865 for starship-design-outgoing; Tue, 2 Jan 2001 19:05:36 -0800 (PST) Received: from imo-r15.mail.aol.com (imo-r15.mx.aol.com [152.163.225.69]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f0335Ym05859 for ; Tue, 2 Jan 2001 19:05:35 -0800 (PST) Received: from curtismanges@netscape.net by imo-r15.mx.aol.com (mail_out_v28.35.) id z.3.62c955 (16246) for ; Tue, 2 Jan 2001 22:05:25 -0500 (EST) Received: from netscape.com (aimmail10.aim.aol.com [205.188.144.202]) by air-in03.mx.aol.com (v77.31) with ESMTP; Tue, 02 Jan 2001 22:05:25 -0500 Mime-Version: 1.0 Message-ID: <38943D3A.715F979C.74D2F445@netscape.net> X-Mailer: Franklin Webmailer 1.0 Content-Type: text/plain; charset="ISO-8859-1" Precedence: bulk Reply-To: curtismanges@netscape.net (Curtis Manges) From: curtismanges@netscape.net (Curtis Manges) Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: [Fwd: Re: starship-design: Going Up? Space Elevator: Next Stop, EarthOrbit] Date: Tue, 02 Jan 2001 22:05:28 -0500 Hmmm -- a lightning rod . . . -------- Original Message -------- Subject: Re: starship-design: Going Up? Space Elevator: Next Stop, EarthOrbit Date: Tue, 2 Jan 2001 17:36:30 -0800 (PST) From: "N. Lindberg" Reply-To: "N. Lindberg" To: KellySt@aol.com Cc: starship design Neat article.  It seems like the nanotubes are the thing.  A question though.  Since nanotubes are (as i recall) electricly conductive, do you think it likely that friction with the atmosphere at lowerlevels, and photoelectric charging in space would tend to induce currents in the cable?  It seems reasonable to me that the potential between one part of the cable and another could be quite high.  Comments? Nels _____________________________________________ Nobody's perfect, but we are working on it.    -Manfred Freiherr von Richthofen When you come to a fork in the road, take it.    -Yogi Berra _____________________________________________ On Tue, 2 Jan 2001 KellySt@aol.com wrote: > > http://www.space.com/businesstechnology/technology/space_elevator_001226.html > > Interesting short article on nanotube based skyhooks, which are now > considered more nearterm then I would have expected. > > Kelly > > > > ========================================================== > Bradley Edwards, a physicist at Los Alamos National >                   Laboratories in New Mexico, is a keen supporter of > fabricating >                   an elevator to space. He recently completed research on >                   lengthy space elevators thanks to a NASA Institute for >                   Advanced Concepts grant. > >                   "The space elevator appears much closer to reality than has >                   been suspected in terms of available technology, cost and >                   schedule," Edwards said. "The major hurdle is the required >                   carbon nanotubes, but that's getting closer each day," he > said. > >                   Edwards has scripted a plan that suggests an operational >                   cable to space can be installed within 10 to 20 years. > __________________________________________________________________ Get your own FREE, personal Netscape Webmail account today at http://webmail.netscape.com/ From VM Wed Jan 3 10:10:07 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["593" "Wednesday" "3" "January" "2001" "00:25:25" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "14" "Re: starship-design: Going Up? Space Elevator: Next Stop, Earth Orbit" "^From:" nil nil "1" nil nil nil nil nil] nil) Content-Length: 593 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f035PeV18929 for starship-design-outgoing; Tue, 2 Jan 2001 21:25:40 -0800 (PST) Received: from imo-r07.mx.aol.com (imo-r07.mx.aol.com [152.163.225.7]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f035Pcm18923 for ; Tue, 2 Jan 2001 21:25:38 -0800 (PST) Received: from KellySt@aol.com by imo-r07.mx.aol.com (mail_out_v28.35.) id z.16.6f364f5 (3706) for ; Wed, 3 Jan 2001 00:25:26 -0500 (EST) Message-ID: <16.6f364f5.278411c5@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: Going Up? Space Elevator: Next Stop, Earth Orbit Date: Wed, 3 Jan 2001 00:25:25 EST In a message dated 1/2/01 7:36:51 PM, nlindber@u.washington.edu writes: >Neat article. It seems like the nanotubes are the thing. A question >though. Since nanotubes are (as i recall) electricly conductive, do you >think it likely that friction with the atmosphere at lowerlevels, and >photoelectric charging in space would tend to induce currents in the >cable? It seems reasonable to me that the potential between one part of >the cable and another could be quite high. Comments? > >Nels Very true. It would be a spectacular lightnight rod, and could cause arcing up to the orbit. From VM Wed Jan 3 10:10:07 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1825" "Tuesday" "2" "January" "2001" "22:34:34" "-0800" "Steve VanDevender" "stevev@efn.org" nil "36" "Re: starship-design: Going Up? Space Elevator: Next Stop, Earth Orbit" "^From:" nil nil "1" nil nil nil nil nil] nil) Content-Length: 1825 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f036YQT08818 for starship-design-outgoing; Tue, 2 Jan 2001 22:34:26 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f036YMm08812 for ; Tue, 2 Jan 2001 22:34:23 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f036YIb17673 for ; Tue, 2 Jan 2001 22:34:18 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f036YZi00231; Tue, 2 Jan 2001 22:34:35 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <14930.51194.182334.887678@localhost.efn.org> In-Reply-To: <16.6f364f5.278411c5@aol.com> References: <16.6f364f5.278411c5@aol.com> X-Mailer: VM 6.89 under 21.1 (patch 12) "Channel Islands" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: Going Up? Space Elevator: Next Stop, Earth Orbit Date: Tue, 2 Jan 2001 22:34:34 -0800 KellySt@aol.com writes: > In a message dated 1/2/01 7:36:51 PM, nlindber@u.washington.edu writes: > > >Neat article. It seems like the nanotubes are the thing. A question > >though. Since nanotubes are (as i recall) electricly conductive, do you > >think it likely that friction with the atmosphere at lowerlevels, and > >photoelectric charging in space would tend to induce currents in the > >cable? It seems reasonable to me that the potential between one part of > >the cable and another could be quite high. Comments? > > > >Nels > > Very true. It would be a spectacular lightnight rod, and could cause arcing > up to the orbit. Either the skyhook cable's a conductor or it's not. If it's a conductor, then a potential difference between the ends of the skyhook will just produce current flow along the cable, which will probably be more of a problem at the anchor site than along the skyhook itself, unless the current flow is so great that it results in resistive heating of the cable to a dangerous level. If it's an insulator, then you might get arcing as potential differences build up, but that would happen primarily in the atmosphere -- you don't get arcing in vacuum, although charge buildup could be a problem for anything that comes in contact with the cable. Lightning rods don't work by attracting lightning; they actually prevent lightning from happening by dissipating the potential difference gradually via corona discharge off the lightning rod's tip. If the skyhook cable is an insulator, then studding it with lightning rods in the atmosphere or running conductors along the part in the atmosphere could help protect it. I certainly don't remember seeing this issue discussed in the articles I've seen about skyhooks, although they tended not to be deeply technical, either. From VM Wed Jan 3 10:10:07 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["467" "Wednesday" "3" "January" "2001" "00:42:42" "-0600" "Gene & James Marlin" "rmarlin@network-one.com" nil "17" "Re: starship-design: Going Up? Space Elevator: Next Stop, Earth Orbit" "^From:" nil nil "1" nil nil nil nil nil] nil) Content-Length: 467 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f036hTF10769 for starship-design-outgoing; Tue, 2 Jan 2001 22:43:29 -0800 (PST) Received: from mail.ayrix.net (mail.ayrix.net [64.49.1.26]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f036hRm10763 for ; Tue, 2 Jan 2001 22:43:28 -0800 (PST) Received: from y4c7d6 ([64.49.6.86]) by mail.ayrix.net (Post.Office MTA v3.5.3 release 223 ID# 0-57710U53000L800S0V35) with SMTP id net for ; Wed, 3 Jan 2001 00:44:15 -0600 Message-ID: <000901c07550$640ed120$56063140@y4c7d6> References: <16.6f364f5.278411c5@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Precedence: bulk Reply-To: rmarlin@network-one.com (Gene & James Marlin) From: rmarlin@network-one.com (Gene & James Marlin) Sender: owner-starship-design@lists.uoregon.edu To: Subject: Re: starship-design: Going Up? Space Elevator: Next Stop, Earth Orbit Date: Wed, 3 Jan 2001 00:42:42 -0600 > Since nanotubes are (as i recall) electricly conductive, It depends on the arrangement of carbon atoms in the tube. The "Barber Pole" arrangement is semiconducting. As I understand it, the more common arrangement is not such a good conductor. > Very true. It would be a spectacular lightnight rod, and >could cause arcing > up to the orbit. Because it is linear and therefore "sharp", and has a high surface area, a coronal discharge seems more likely. Gene From VM Tue Feb 6 10:30:54 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["10666" "Tuesday" "6" "February" "2001" "10:05:22" "-0600" "Johnny Thunderbird" "jthunderbird@nternet.com" nil "225" "starship-design: Faster Than Light Vehicles" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 10666 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f16G42F18987 for starship-design-outgoing; Tue, 6 Feb 2001 08:04:02 -0800 (PST) Received: from eagle.nternet.com (eagle.nternet.com [208.60.58.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with SMTP id f16G41518979 for ; Tue, 6 Feb 2001 08:04:01 -0800 (PST) Received: (qmail 6689 invoked from network); 6 Feb 2001 16:02:54 -0000 Received: from unknown (HELO nless) (66.21.216.190) by eagle.nternet.com with SMTP; 6 Feb 2001 16:02:54 -0000 Message-ID: <001401c09056$9d8e26a0$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0011_01C09024.514877A0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "Johnny Thunderbird" From: "Johnny Thunderbird" Sender: owner-starship-design@lists.uoregon.edu To: Subject: starship-design: Faster Than Light Vehicles Date: Tue, 6 Feb 2001 10:05:22 -0600 This is a multi-part message in MIME format. ------=_NextPart_000_0011_01C09024.514877A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Alternative Cosmology Offers FTL Transport Tom van Flandern, an astronomer formerly of the Naval Observatory, now a = full-time heretic, offers a full stem-to-stern housecleaning of = cosmology at his website, http://www.metaresearch.org which is = absolutely essential reading for folks into astrophysics. Astronomy has gone into an inflationary phase, so to speak, in the past = 3-5 years, due to order of magnitude increases in the new observational = capabilities made available to our species recently: planetary probes, = orbiting EUV, Xray, and gamma ray observatories, the Hubble, VLBI radio = networks, vastly larger dirtside optical telescopes, adaptive optics, = etc. We see the universe lots better than we used to, and it's a very = confusing place. Seems hardly a week goes by without some new = observation "challenging" the basis of standard theories, requiring a = paradigm shift. Big Bang cosmology is in a heap of trouble, for it can = hardly keep up with all the adjustments it has to make to keep itself = from looking like an elaborate fantasy. New cosmologies wait hungrily in = the wings, watching for signs of weakness. Van Flandern (in papers published in Astrophysics Journal and Physical = Review Letters) offers his "Meta Model" cosmology which mercilessly cuts = the standard interpretations off at the knees. He favors a = quasi-steady-state cosmology, differing from the MOND (Modified = Newtonian Dynamics) model by hypothesizing a characteristic path length = (~2 kiloparsec) for gravity, beyond which its attraction decays, = completely avoiding any requirement for dark matter supplements to = explain galactic motions. There are lots of observations he can explain = this way that assorted flavors of Big Bang theory are having a very = awkward time with. But that's not the funny part. Space theories aren't = sexy without bangs of some sort, so he has a solar system dynamics = reminiscent of Velikovsky or Donelly bashing their planets around, = except van Flandern has his planets popping spontaneously without = waiting for cosmic billiards impacts. Planetary cores are hot and = pressurized; cooling induces phase changes, which can suddenly change = the size they need for lebensraum, and a planetary crust ain't gonna = hold it in. Hot superfluids get into cold vacuum, and lo, they vaporize, = whereas, big time. He calls this his "Exploded Planets Hypothesis", but = that's not the funny part either. The funny part is about his relativity theory: to replace GTR (General = Theory of Relativity) as an explanation for gravity, his groundwork = involves adopting Lorentzian Relativity (LR) instead of Einstein's = Special Theory of Relativity (STR). LR, it turns out, is practically = indistinguishable from STR within the framework of tests which have been = conducted to date, actually fitting more comfortably with the data in = many cases with moving clocks (like GPS satellites are). The atomic = clocks in GPS satellites are precompensated for relativistic effects = before launch, so when in orbit they keep perfect synchrony with each = other and with ground clocks, although in Einstein's theory this would = be forbidden! Lorentz relativity allows Earth's gravity well to = establish a preferred "local" coordinate system, which Einstein would = disallow; the clocks work, when STR says they couldn't. But the feature = of all this mathematizing which should be of most interest to starship = designers, such as me and thee, is that Lorentzian relativity has = absolutely no requirement that the speed of light establish a maximum = velocity. There have been a spate of recent experiments in physics labs which have = shown "superluminal" transmission of signals, actual information, = transferred faster than C. Phase velocity, group velocity, signal = velocity, all the speed limits have apparently been broken by quantum = tunneling. These results are in contradiction to Einstein's STR but are = taken in stride by LR. See van Flandern's web site for the details, but = it looks to me like we have some rethinking to do as starship designers. = He never mentions the possibility there, of accelerating matter to = superluminal velocity, but I just did. To my mind, the quandry that it's = supposed to take "infinite" energy to accelerate a mass to lightspeed, = because its mass would increase to "infinity", may be another delusion = like other supposed "infinitudes" have proved to be. Philosophically, I = am prejudiced against all forms of unlimited quantitative growth curves = in nature, because I honestly don't believe in them. So let's find out, = shall we? Johnny Thunderbird http://fly.to/heavylight ------=_NextPart_000_0011_01C09024.514877A0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Alternative Cosmology Offers FTL=20 Transport
 
Tom van Flandern, an astronomer = formerly of the=20 Naval Observatory, now a full-time heretic, offers a full stem-to-stern=20 housecleaning of cosmology at his website, http://www.metaresearch.org = which is=20 absolutely essential reading for folks into astrophysics.
 
Astronomy has gone into an inflationary = phase, so=20 to speak, in the past 3-5 years, due to order of magnitude increases in = the new=20 observational capabilities made available to our species recently: = planetary=20 probes, orbiting EUV, Xray, and gamma ray observatories, the Hubble, = VLBI radio=20 networks, vastly larger dirtside optical telescopes, adaptive optics, = etc. We=20 see the universe lots better than we used to, and it's a very confusing = place.=20 Seems hardly a week goes by without some new observation "challenging" = the basis=20 of standard theories, requiring a paradigm shift. Big Bang cosmology is = in a=20 heap of trouble, for it can hardly keep up with all the adjustments it = has to=20 make to keep itself from looking like an elaborate fantasy. New = cosmologies wait=20 hungrily in the wings, watching for signs of weakness.
 
Van Flandern (in papers published in = Astrophysics=20 Journal and Physical Review Letters) offers his "Meta Model" cosmology = which=20 mercilessly cuts the standard interpretations off at the knees. He = favors a=20 quasi-steady-state cosmology, differing from the MOND (Modified = Newtonian=20 Dynamics) model by hypothesizing a characteristic path length (~2 = kiloparsec)=20 for gravity, beyond which its attraction decays, completely avoiding any = requirement for dark matter supplements to explain galactic motions. = There are=20 lots of observations he can explain this way that assorted flavors of = Big Bang=20 theory are having a very awkward time with. But that's not the funny = part. Space=20 theories aren't sexy without bangs of some sort, so he has a solar = system=20 dynamics reminiscent of Velikovsky or Donelly bashing their planets = around,=20 except van Flandern has his planets popping spontaneously without = waiting for=20 cosmic billiards impacts. Planetary cores are hot and pressurized; = cooling=20 induces phase changes, which can suddenly change the size they need for=20 lebensraum, and a planetary crust ain't gonna hold it in. Hot = superfluids get=20 into cold vacuum, and lo, they vaporize, whereas, big time. He calls = this his=20 "Exploded Planets Hypothesis", but that's not the funny part=20 either.
 
The funny part is about his relativity = theory: to=20 replace GTR (General Theory of Relativity) as an explanation for = gravity, his=20 groundwork involves adopting Lorentzian Relativity (LR) instead of = Einstein's=20 Special Theory of Relativity (STR). LR, it turns out, is practically=20 indistinguishable from STR within the framework of tests which have been = conducted to date, actually fitting more comfortably with the data in = many cases=20 with moving clocks (like GPS satellites are). The atomic clocks in GPS=20 satellites are precompensated for relativistic effects before launch, so = when in=20 orbit they keep perfect synchrony with each other and with ground = clocks,=20 although in Einstein's theory this would be forbidden! Lorentz = relativity allows=20 Earth's gravity well to establish a preferred "local" coordinate system, = which=20 Einstein would disallow; the clocks work, when STR says they couldn't. = But the=20 feature of all this mathematizing which should be of most interest to = starship=20 designers, such as me and thee, is that Lorentzian relativity has = absolutely no=20 requirement that the speed of light establish a maximum = velocity.
 
There have been a spate of recent = experiments in=20 physics labs which have shown "superluminal" transmission of signals, = actual=20 information, transferred faster than C. Phase velocity, group velocity, = signal=20 velocity, all the speed limits have apparently been broken by quantum = tunneling.=20 These results are in contradiction to Einstein's STR but are taken in = stride by=20 LR. See van Flandern's web site for the details, but it looks to me like = we have=20 some rethinking to do as starship designers. He never mentions the = possibility=20 there, of accelerating matter to superluminal velocity, but I just did. = To my=20 mind, the quandry that it's supposed to take "infinite" energy to = accelerate a=20 mass to lightspeed, because its mass would increase to "infinity", may = be=20 another delusion like other supposed "infinitudes" have proved to be.=20 Philosophically, I am prejudiced against all forms of unlimited = quantitative=20 growth curves in nature, because I honestly don't believe in them. So = let's find=20 out, shall we?
 
Johnny Thunderbird
http://fly.to/heavylight
------=_NextPart_000_0011_01C09024.514877A0-- From VM Tue Feb 6 11:26:07 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["4164" "Tuesday" "6" "February" "2001" "13:06:57" "-0600" "Johnny Thunderbird" "jthunderbird@nternet.com" nil "95" "starship-design: Proton-Lithium Fusion Drive" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 4164 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f16J5Zu04096 for starship-design-outgoing; Tue, 6 Feb 2001 11:05:35 -0800 (PST) Received: from eagle.nternet.com (eagle.nternet.com [208.60.58.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with SMTP id f16J5Y504079 for ; Tue, 6 Feb 2001 11:05:34 -0800 (PST) Received: (qmail 6023 invoked from network); 6 Feb 2001 19:04:33 -0000 Received: from unknown (HELO nless) (66.21.216.190) by eagle.nternet.com with SMTP; 6 Feb 2001 19:04:33 -0000 Message-ID: <000e01c0906f$fbd231c0$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_000B_01C0903D.AF5A2820" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "Johnny Thunderbird" From: "Johnny Thunderbird" Sender: owner-starship-design@lists.uoregon.edu To: Subject: starship-design: Proton-Lithium Fusion Drive Date: Tue, 6 Feb 2001 13:06:57 -0600 This is a multi-part message in MIME format. ------=_NextPart_000_000B_01C0903D.AF5A2820 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable p + 7.Li --> 2 (4.He) + 17.3 ev Having been a longtime advocate of proton-beryllium fusion reaction as a = spaceship drive, when I heard of the proton-lithium cycle I immediately = converted because of the universal abundance of lithium compared to = beryllium. Both these cycles have the insuperable advantage of not = yielding neutrons, as do other fusion cycles, making them clean and not = dirty. My proposal for a compact space drive includes a lithium electric = arc centered between cyclotron dees, to project lithium ions through = gaseous hydrogen, as the basis for a fusion drive. Lithium is not as = abundant as hydrogen, which suggests it should be the accelerated = species, that a higher proportion of it might be involved in fusion = reactions. The ideal material for a combustion chamber would be 12.C = isotopic CVD (chemical vapor deposition) diamond deposited over cooling = channels through which liquid hydrogen circulates; no solid material = conducts heat better than diamond made of carbon-12, nor does any = element carry heat away faster than hydrogen, superfluid helium III = excepted, for which cryogenic requirements are too strict for use in = engines. Diamond can be used only because there are no oxidizing = conditions present, and under reducing conditions diamond will serve as = a fair refractory, so long as its temperature can be kept below its = sublimation point. As with any rocket drive, I would wrap a = superconducting coil around the exit jet, for the magnetoplasmadynamic = benefits. Johnny Thunderbird http://personal.msy.bellsouth.net/msy/b/u/bugzappr ------=_NextPart_000_000B_01C0903D.AF5A2820 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
p + 7.Li --> 2 (4.He) + 17.3 = ev
 
Having been a longtime advocate of = proton-beryllium=20 fusion reaction as a spaceship drive, when I heard of the proton-lithium = cycle I=20 immediately converted because of the universal abundance of lithium = compared to=20 beryllium. Both these cycles have the insuperable advantage of not = yielding=20 neutrons, as do other fusion cycles, making them clean and not dirty. My = proposal for a compact space drive includes a lithium electric arc = centered=20 between cyclotron dees, to project lithium ions through gaseous = hydrogen, as the=20 basis for a fusion drive. Lithium is not as abundant as hydrogen, which = suggests=20 it should be the accelerated species, that a higher proportion of it = might be=20 involved in fusion reactions. The ideal material for a combustion = chamber would=20 be 12.C isotopic CVD (chemical vapor deposition) diamond deposited over = cooling=20 channels through which liquid hydrogen circulates; no solid material = conducts=20 heat better than diamond made of carbon-12, nor does any element carry = heat away=20 faster than hydrogen, superfluid helium III excepted, for which = cryogenic=20 requirements are too strict for use in engines. Diamond can be used only = because=20 there are no oxidizing conditions present, and under reducing conditions = diamond=20 will serve as a fair refractory, so long as its temperature can be kept = below=20 its sublimation point. As with any rocket drive, I  would wrap a=20 superconducting coil around the exit jet, for the magnetoplasmadynamic=20 benefits.
 
Johnny Thunderbird
http://personal.msy.bellsouth.net/msy/b/u/bugzappr
<= /BODY> ------=_NextPart_000_000B_01C0903D.AF5A2820-- From VM Tue Feb 6 12:07:49 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2131" "Saturday" "3" "February" "2001" "19:24:02" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "41" "Re: starship-design: Proton-Lithium Fusion Drive" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 2131 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f16JtP705918 for starship-design-outgoing; Tue, 6 Feb 2001 11:55:25 -0800 (PST) Received: from main.jetnet.ab.ca (root@jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f16JtL505828 for ; Tue, 6 Feb 2001 11:55:21 -0800 (PST) Received: from jetnet.ab.ca (dialin34.jetnet.ab.ca [207.153.6.34]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id MAA24558 for ; Tue, 6 Feb 2001 12:46:40 -0700 (MST) Message-ID: <3A7CBD42.D13A9853@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: <000e01c0906f$fbd231c0$0a0a0a0a@nless> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: Proton-Lithium Fusion Drive Date: Sat, 03 Feb 2001 19:24:02 -0700 For all the people who can't read stupid attached files. Johnny Thunderbird wrote: > p + 7.Li --> 2 (4.He) + 17.3 ev > > Having been a longtime advocate of proton-beryllium fusion > reaction as a spaceship drive, when I heard of the > proton-lithium cycle I immediately converted because of the > universal abundance of lithium compared to beryllium. Both > these cycles have the insuperable advantage of not yielding > neutrons, as do other fusion cycles, making them clean and not > dirty. My proposal for a compact space drive includes a lithium > electric arc centered between cyclotron dees, to project > lithium ions through gaseous hydrogen, as the basis for a > fusion drive. Lithium is not as abundant as hydrogen, which > suggests it should be the accelerated species, that a higher > proportion of it might be involved in fusion reactions. The > ideal material for a combustion chamber would be 12.C isotopic > CVD (chemical vapor deposition) diamond deposited over cooling > channels through which liquid hydrogen circulates; no solid > material conducts heat better than diamond made of carbon-12, > nor does any element carry heat away faster than hydrogen, > superfluid helium III excepted, for which cryogenic > requirements are too strict for use in engines. Diamond can be > used only because there are no oxidizing conditions present, > and under reducing conditions diamond will serve as a fair > refractory, so long as its temperature can be kept below its > sublimation point. As with any rocket drive, I would wrap a > superconducting coil around the exit jet, for the > magnetoplasmadynamic benefits. > > Johnny Thunderbird To all would be fusion drive designers - it looks good on paper can we build it? Check here for answers. http://fusor.blogspot.com/ The speed of dark. Some interesting new ideas on light from autodynamics make change space propulsion. http://www.autodynamics.org/new99/Atomic/PhotoRest/index.html -- "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk From VM Wed Feb 7 10:00:58 2001 X-VM-v5-Data: ([nil nil nil nil t nil nil nil nil] ["1133" "Wednesday" "7" "February" "2001" "02:37:39" "-0600" "Johnny Thunderbird" "jthunderbird@nternet.com" "<000701c090e1$3b6b4120$0a0a0a0a@nless>" "21" "starship-design: Attatchmment?" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1133 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f178aU714098 for starship-design-outgoing; Wed, 7 Feb 2001 00:36:30 -0800 (PST) Received: from eagle.nternet.com (eagle.nternet.com [208.60.58.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with SMTP id f178aT514091 for ; Wed, 7 Feb 2001 00:36:29 -0800 (PST) Received: (qmail 3527 invoked from network); 7 Feb 2001 08:35:24 -0000 Received: from unknown (HELO nless) (66.21.216.190) by eagle.nternet.com with SMTP; 7 Feb 2001 08:35:24 -0000 Message-ID: <000701c090e1$3b6b4120$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "Johnny Thunderbird" From: "Johnny Thunderbird" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: starship-design: Attatchmment? Date: Wed, 7 Feb 2001 02:37:39 -0600 Anybody else besides Ben have trouble seeing my post? My mail client sends HTML as the default. I know people who use pine (for example) for a client, don't see that too well. I didn't attatch anything, just typed and sent. My echo from the list looked just like what I sent. Well, I've changed the default to plain text, in case anybody else has that problem. Or was that a grammatical criticism? Long sentences aren't ungrammatical in themselves, though they may not be as readable as conversational mode. If you're into fusion and relativity, maybe you can unscramble my sentence construction with a bit of effort. I seem to recall we did something like this last year, where I proposed accelerator fusion and you came back with Farnsworth. Good stuff, just not as straightforward as slamming particles into each other, and not so obviously a simple space drive. Note that fusion which produces only alphas does not initiate chain reactions, doesn't do anything else complicated, just shoots stuff out the back. Check out that http://www.metaresearch.org if you haven't already. Johnny T. http://www.geocities.com/jthunderbird From VM Wed Feb 7 10:20:48 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1102" "Wednesday" "7" "February" "2001" "10:09:53" "-0800" "Steve VanDevender" "stevev@darkwing.uoregon.edu" nil "20" "starship-design: Attatchmment?" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1102 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f17I9sS26510 for starship-design-outgoing; Wed, 7 Feb 2001 10:09:54 -0800 (PST) Received: (from stevev@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f17I9rj26501; Wed, 7 Feb 2001 10:09:53 -0800 (PST) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <14977.36721.5203.796247@darkwing.uoregon.edu> In-Reply-To: <000701c090e1$3b6b4120$0a0a0a0a@nless> References: <000701c090e1$3b6b4120$0a0a0a0a@nless> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "Johnny Thunderbird" Cc: "Starship Design List" Subject: starship-design: Attatchmment? Date: Wed, 7 Feb 2001 10:09:53 -0800 Johnny Thunderbird writes: > Anybody else besides Ben have trouble seeing my post? > > My mail client sends HTML as the default. I know people who use pine (for > example) for a client, don't see that too well. I didn't attatch anything, > just typed and sent. My echo from the list looked just like what I sent. > Well, I've changed the default to plain text, in case anybody else has that > problem. I recommend to all posters to avoid redundant HTML attachments. Besides causing problems for many mail readers, they make messages 2-3 times larger than they need to be without adding anything useful. Also, as a reminder, postings over 40,000 bytes in size will be bounced to me for manual approval. I may manually approve postings that aren't too much over the limit if they have merit (i.e. a sufficiently lengthy discussion, one of the space newsletters that Lee occasionally forwards, etc.) but in general you should avoid sending large messages to the list. And, if you have redundant HTML attachments turned on, that'll make a 20,000 character plaintext posting go over the limit. From VM Wed Feb 7 14:14:24 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1510" "Wednesday" "7" "February" "2001" "16:04:34" "-0600" "L. Parker" "lparker@cacaphony.net" "<005601c09152$231972b0$0100a8c0@broadsword>" "32" "starship-design: Thoughts on antimatter and fusion..." "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1510 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f17M6kh03251 for starship-design-outgoing; Wed, 7 Feb 2001 14:06:47 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f17M6jQ03233 for ; Wed, 7 Feb 2001 14:06:45 -0800 (PST) Received: from broadsword (p449.gnt.com [204.49.91.65]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id QAA26281 for ; Wed, 7 Feb 2001 16:06:41 -0600 Message-ID: <005601c09152$231972b0$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "Starship-Design \(E-mail\)" Subject: starship-design: Thoughts on antimatter and fusion... Date: Wed, 7 Feb 2001 16:04:34 -0600 While reading a recent post a thought occurred to me. Forgetting for the moment that ANY drive that requires reaction mass is inherently unsuited for Interstellar space... Everyone has always assumed that the epitome of reaction drives is the Antimatter Drive. The basis for this belief has been the supposition that since antimatter/matter reaction is the ONLY way to get 100 percent conversion of mass to energy, then it would naturally be the ONLY way to get nearly 100 percent efficiency out of the engine. Here is the thought: The key here is getting 100 percent conversion of mass to energy, NOT the antimatter/matter reaction. What we are actually looking for is ANY method of converting a given amount of mass into 100 percent energy, preferably in a (somewhat) controlled manner. So perhaps we should expand our thinking a little. There might be some method (don't ask me, I'm just brainstorming) to persuade matter to give up its all without resorting to antimatter. Maybe there is some way of causing a stick of beryllium to turn into a coherent beam of gamma radiation without wasting an enormous amount of energy in the process. This would constitute a photon drive, every bit as efficient as antimatter/matter conversion. Or perhaps, along the line of the guns in Hammer's Slammers, some interesting construction of plastic that merely requires a moderate amount of current to set it off. Or maybe we could create and focus a directed release of vacuum energy, now THERE is an idea... Lee From VM Wed Feb 7 14:49:53 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2214" "Wednesday" "7" "February" "2001" "14:40:30" "-0800" "Steve VanDevender" "stevev@efn.org" nil "40" "starship-design: Thoughts on antimatter and fusion..." "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 2214 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f17Melt23810 for starship-design-outgoing; Wed, 7 Feb 2001 14:40:47 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f17MejQ23791 for ; Wed, 7 Feb 2001 14:40:46 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f17MehZ08436 for ; Wed, 7 Feb 2001 14:40:43 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f17MeVg17327; Wed, 7 Feb 2001 14:40:31 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <14977.52958.450520.114735@tzadkiel.efn.org> In-Reply-To: <005601c09152$231972b0$0100a8c0@broadsword> References: <005601c09152$231972b0$0100a8c0@broadsword> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "Starship-Design \(E-mail\)" Subject: starship-design: Thoughts on antimatter and fusion... Date: Wed, 7 Feb 2001 14:40:30 -0800 L. Parker writes: > While reading a recent post a thought occurred to me. Forgetting for the > moment that ANY drive that requires reaction mass is inherently unsuited for > Interstellar space... > > Everyone has always assumed that the epitome of reaction drives is the > Antimatter Drive. The basis for this belief has been the supposition that > since antimatter/matter reaction is the ONLY way to get 100 percent > conversion of mass to energy, then it would naturally be the ONLY way to get > nearly 100 percent efficiency out of the engine. > > Here is the thought: > > The key here is getting 100 percent conversion of mass to energy, NOT the > antimatter/matter reaction. What we are actually looking for is ANY method > of converting a given amount of mass into 100 percent energy, preferably in > a (somewhat) controlled manner. So perhaps we should expand our thinking a > little. There might be some method (don't ask me, I'm just brainstorming) to > persuade matter to give up its all without resorting to antimatter. > > Maybe there is some way of causing a stick of beryllium to turn into a > coherent beam of gamma radiation without wasting an enormous amount of > energy in the process. This would constitute a photon drive, every bit as > efficient as antimatter/matter conversion. Actually, I think I've said much the same thing in the past. The theoretically maximally efficient reaction drive would convert fuel mass entirely to photons. In fact, matter/antimatter reactions aren't 100% efficient at converting mass to photons, partly because it's hard to get a complete reaction and even if the reaction is complete not all of the reaction products are photons. I'm not expert enough at particle physics to know if there's any deep reason why converting a quantity of mass (as opposed to equal quantities of matter and antimatter) entirely to photons would be difficult or impossible. I suspect that some of the more subtle conservation laws in particle physics may prevent 100% complete conversion. In fact, there are things that probably also come into play like the charge-parity asymmetry which makes matter more prevalent in the universe than antimatter. From VM Wed Feb 7 16:49:04 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["218" "Wednesday" "7" "February" "2001" "19:27:02" "-0500" "Connor Ireland" "chithree@boo.net" nil "5" "Re: starship-design: Thoughts on antimatter and fusion..." "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 218 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f180WkN04629 for starship-design-outgoing; Wed, 7 Feb 2001 16:32:46 -0800 (PST) Received: from boo-mda02.boo.net (IDENT:root@boo-mda02.boo.net [216.200.67.22]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f180WjQ04616 for ; Wed, 7 Feb 2001 16:32:45 -0800 (PST) Received: from 0018514826 (dc-lata-1-106.dynamic-dialup.coretel.net [162.33.62.106]) by boo-mda02.boo.net (8.9.3/8.9.3) with SMTP id TAA28379 for ; Wed, 7 Feb 2001 19:32:25 -0500 Message-ID: <002801c09165$df151880$6a3e21a2@0018514826> References: <005601c09152$231972b0$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.00.2615.200 X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2615.200 Precedence: bulk Reply-To: "Connor Ireland" From: "Connor Ireland" Sender: owner-starship-design@lists.uoregon.edu To: "Starship-Design (E-mail)" Subject: Re: starship-design: Thoughts on antimatter and fusion... Date: Wed, 7 Feb 2001 19:27:02 -0500 > Or maybe we could create and focus a directed release of vacuum energy, > now THERE is an idea... I already thought of that. Remember my Casimir Forward baloon from a year or two ago? I can understand if you don't. From VM Thu Feb 8 10:06:26 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1887" "Wednesday" "7" "February" "2001" "19:15:42" "-0600" "L. Parker" "lparker@cacaphony.net" nil "42" "RE: starship-design: Thoughts on antimatter and fusion..." "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1887 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f181vaY19246 for starship-design-outgoing; Wed, 7 Feb 2001 17:57:36 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f181vZQ19237 for ; Wed, 7 Feb 2001 17:57:35 -0800 (PST) Received: from broadsword (p470.gnt.com [204.49.91.86]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id TAA05721 for ; Wed, 7 Feb 2001 19:57:34 -0600 Message-ID: <005701c09172$61fd1890$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 In-Reply-To: <14977.52958.450520.114735@tzadkiel.efn.org> Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "'Starship-Design \(E-mail\)'" Subject: RE: starship-design: Thoughts on antimatter and fusion... Date: Wed, 7 Feb 2001 19:15:42 -0600 > Actually, I think I've said much the same thing in the past. The > theoretically maximally efficient reaction drive would > convert fuel mass > entirely to photons. In fact, matter/antimatter reactions aren't 100% > efficient at converting mass to photons, partly because it's > hard to get > a complete reaction and even if the reaction is complete not > all of the > reaction products are photons. > > I'm not expert enough at particle physics to know if there's any deep > reason why converting a quantity of mass (as opposed to equal > quantities > of matter and antimatter) entirely to photons would be difficult or > impossible. I suspect that some of the more subtle > conservation laws in > particle physics may prevent 100% complete conversion. In fact, there > are things that probably also come into play like the charge-parity > asymmetry which makes matter more prevalent in the universe than > antimatter. I'm guessing here, but besides the obvious thermodynamic problems, I believe that there is also a chaotic component of most reactions that make them inherently inefficient. But what I was getting at is that it may be possible once we understand the nature of matter a little better, to simply coerce it into changing states in an organized manner to produce nearly one hundred percent efficient thrust. Of course, I have no idea now how that might be done... However, I'm still with Marc Millis on the precept that true interstellar flight requires a "breakthrough" in propulsion physics, that reaction drives are NOT the answer. What I just described is an evolutionary approach, not a revolutionary approach. My personal favorite has always been inertia, which seems to be yielding a few hints of being manipulable based on recent theoretical work. One can always hope, meanwhile, we keep whittling away at what we know works to make it better... Lee From VM Thu Feb 8 10:06:26 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1398" "Wednesday" "7" "February" "2001" "19:54:41" "-0600" "L. Parker" "lparker@cacaphony.net" nil "24" "starship-design: =?iso-8859-1?Q?Millis's_hypothetical_=22Space_Drives=22_?=" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1398 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f181vcZ19256 for starship-design-outgoing; Wed, 7 Feb 2001 17:57:38 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f181vbQ19249 for ; Wed, 7 Feb 2001 17:57:37 -0800 (PST) Received: from broadsword (p470.gnt.com [204.49.91.86]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id TAA05735 for ; Wed, 7 Feb 2001 19:57:37 -0600 Message-ID: <005801c09172$66220a20$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 Importance: Normal Content-Transfer-Encoding: 8bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "Starship-Design \(E-mail\)" Subject: starship-design: =?iso-8859-1?Q?Millis's_hypothetical_=22Space_Drives=22_?= Date: Wed, 7 Feb 2001 19:54:41 -0600 Millis’s hypothetical "Space Drives" A "space drive" can be defined as an idealized form of propulsion where the fundamental properties of matter and spacetime are used to create propulsive forces anywhere in space without having to carry and expel a reaction mass. Such an achievement would revolutionize space travel as it would circumvent the need for propellant. A variety of hypothetical space drives were created and analyzed by Millis to identify the specific problems that have to be solved to make such schemes plausible. These hypothetical drives are just briefly introduced here. Please note that these concepts are purely hypothetical constructs aimed to illustrate the remaining challenges. Before any of these space drives can become reality, a method must be discovered where a vehicle can create and control an external asymmetric force on itself without expelling a reaction mass and the method must satisfy conservation laws in the process. [Note: This section is excerpted from Millis' "Challenge to Create the Space Drive," in the AIAA Journal of Propulsion and Power, Vol.13, No.5, pp. 577-582, Sept.-Oct. 1997. This 6 page report uses 7 hypothetical space drive concepts to highlight the unsolved physics and candidate next steps toward creating a propellantless space drive. It also contains figures for each concept which are not currently available electronically.] Lee From VM Thu Feb 8 15:47:45 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["317" "Thursday" "8" "February" "2001" "17:16:29" "-0500" "Curtis Manges" "curtismanges@netscape.net" nil "3" "starship-design: various antimatter, etc., drives" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 317 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f18MHB621745 for starship-design-outgoing; Thu, 8 Feb 2001 14:17:11 -0800 (PST) Received: from imo-r18.mx.aol.com (imo-r18.mx.aol.com [152.163.225.72]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f18MH9Q21585 for ; Thu, 8 Feb 2001 14:17:09 -0800 (PST) Received: from curtismanges@netscape.net by imo-r18.mx.aol.com (mail_out_v29.5.) id z.4.cc2528 (16232) for ; Thu, 8 Feb 2001 17:16:45 -0500 (EST) Received: from netscape.com (aimmail06.aim.aol.com [205.188.144.198]) by air-in02.mx.aol.com (v77_r1.21) with ESMTP; Thu, 08 Feb 2001 17:16:45 1900 Mime-Version: 1.0 Message-ID: <35E7C9AA.64D57683.74D2F445@netscape.net> X-Mailer: Franklin Webmailer 1.0 Content-Type: text/plain; charset="us-ascii" Precedence: bulk Reply-To: curtismanges@netscape.net (Curtis Manges) From: curtismanges@netscape.net (Curtis Manges) Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: starship-design: various antimatter, etc., drives Date: Thu, 08 Feb 2001 17:16:29 -0500 Something other than reaction drives -- I agree, and my favorite is gravity control. Though, while on the subject of photon drives, how about a big old laser? __________________________________________________________________ Get your own FREE, personal Netscape Webmail account today at http://webmail.netscape.com/ From VM Thu Feb 8 16:07:38 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1289" "Thursday" "8" "February" "2001" "17:56:38" "-0600" "L. Parker" "lparker@cacaphony.net" nil "25" "RE: starship-design: various antimatter, etc., drives" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1289 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f18Nvt228688 for starship-design-outgoing; Thu, 8 Feb 2001 15:57:55 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f18NvsQ28680 for ; Thu, 8 Feb 2001 15:57:54 -0800 (PST) Received: from broadsword (p439.gnt.com [204.49.91.55]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id RAA24001; Thu, 8 Feb 2001 17:57:42 -0600 Message-ID: <007001c0922a$cf5bde40$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 In-Reply-To: <35E7C9AA.64D57683.74D2F445@netscape.net> Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "'Curtis Manges'" , Subject: RE: starship-design: various antimatter, etc., drives Date: Thu, 8 Feb 2001 17:56:38 -0600 > Something other than reaction drives -- I agree, and my > favorite is gravity control. Though, while on the subject of > photon drives, how about a big old laser? Only if efficiency jumps to near one hundred percent, in which case it would be a photon drive. Current lasers are extremely inefficient in the power regimes that would produce even a milligram of thrust. Reasonably efficient lasers such as diode lasers are not scalable to a degree where they could produce useful thrust. The "hypothetical" laser in Hammer's Slammers still produces a great deal of waste heat and even the smallest handheld weapon is millions of times more powerful than all but the largest current lasers. Even so, a photon drive still falls in the class of carrying fuel with you. Control over inertia might allow us to achieve greater velocities from less onboard reaction mass in the near term, gravity control might let us "surf" the currents of space, but if some of the new theories work out, space may turn out to have substance after all, in which case it may be possible to simply grab it and "pull" (or push). Either way, inertia control would allow us to accelerate much faster and achieve higher velocities much more quickly without becoming a sticky green goo on the aft bulkhead... Lee From VM Sat Feb 10 16:32:01 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1109" "Friday" "9" "February" "2001" "19:12:28" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "34" "Re: starship-design: Thoughts on antimatter and fusion..." "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1109 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1A0DWR27329 for starship-design-outgoing; Fri, 9 Feb 2001 16:13:32 -0800 (PST) Received: from imo-r05.mx.aol.com (imo-r05.mx.aol.com [152.163.225.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1A0DNQ27294 for ; Fri, 9 Feb 2001 16:13:23 -0800 (PST) Received: from KellySt@aol.com by imo-r05.mx.aol.com (mail_out_v29.5.) id 4.45.22b32be (3946); Fri, 9 Feb 2001 19:12:28 -0500 (EST) Message-ID: <45.22b32be.27b5e16c@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: lparker@cacaphony.net, starship-design@lists.uoregon.edu Subject: Re: starship-design: Thoughts on antimatter and fusion... Date: Fri, 9 Feb 2001 19:12:28 EST In a message dated 2/7/01 8:02:11 PM, lparker@cacaphony.net writes: > >But what I was getting at is that it may be possible once we understand >the >nature of matter a little better, to simply coerce it into changing states >in an organized manner to produce nearly one hundred percent efficient >thrust. Of course, I have no idea now how that might be done... Agreed. A direct mass energy conversion concept would be a great idea, and might be possible -- somehow? >However, I'm still with Marc Millis on the precept that true interstellar >flight requires a "breakthrough" in propulsion physics, that reaction drives >are NOT the answer. What I just described is an evolutionary approach, >not a >revolutionary approach. > > My personal favorite has always been inertia, which seems to be yielding >a >few hints of being manipulable based on recent theoretical work. One can >always hope, meanwhile, we keep whittling away at what we know works to >make >it better... > >Lee I also note that kinetic energy is something we don't understand, and hence might be able to play games with. ;0 Kelly From VM Mon Feb 12 10:19:35 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1619" "Monday" "12" "February" "2001" "06:01:58" "-0600" "Johnny Thunderbird" "jthunderbird@nternet.com" nil "29" "Re: starship-design: Thoughts on antimatter and fusion..." "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1619 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1CCwZQ03723 for starship-design-outgoing; Mon, 12 Feb 2001 04:58:35 -0800 (PST) Received: from eagle.nternet.com (eagle.nternet.com [208.60.58.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with SMTP id f1CCwXQ03717 for ; Mon, 12 Feb 2001 04:58:33 -0800 (PST) Received: (qmail 10551 invoked from network); 12 Feb 2001 12:57:24 -0000 Received: from unknown (HELO nless) (208.60.58.77) by eagle.nternet.com with SMTP; 12 Feb 2001 12:57:24 -0000 Message-ID: <000a01c094eb$9add6580$4d3a3cd0@nless> References: <005601c09152$231972b0$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "Johnny Thunderbird" From: "Johnny Thunderbird" Sender: owner-starship-design@lists.uoregon.edu To: "L. Parker" , "Starship-Design \(E-mail\)" Subject: Re: starship-design: Thoughts on antimatter and fusion... Date: Mon, 12 Feb 2001 06:01:58 -0600 > ANY drive that requires reaction mass is inherently unsuited for > Interstellar space... It's unwarranted to dismiss the reaction drive out of hand. That's the only thing that we know works. We have firm physical expectation that the photon drive will work, but no concrete reason to believe it preferable to rocketry. We can also expect that acceleration may be available from crossing magnetic lines of force, which are demonstrably present in interstellar space, for electric motors work that way. However, no net impetus is attained parallel to such lines of force. Electromagnetic drives won't get you much of anywhere. These three possibilities exhaust the physically demonstrated principles for space drives, and beyond these lies ectoplasmic vaporware. I feel it's presumptuous to reject rocketry for the flashlight drive, when no one has a clue how the photons might be generated. Respondents here favor the (near) perfect conversion of mass to energy; so do we all. Until we know how to perfectly transduce one form of energy into another, say electricity into light, this is not even theorizing, just wishful thinking. I'd like to get some engineering done, show us the iron. OK, a resistance heater will perfectly transform electrical energy into (mostly infrared) light, but this has a blackbody spectrum, can't be collimated, so makes a lousy drive. I think what I proposed last year, a relativistic linear accelerator for a reaction drive, will equal or beat (in terms of efficiency) any specific proposal you can produce for a drive based on photons generated onboard the ship. Johnny Thunderbird From VM Mon Feb 12 13:40:02 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2098" "Monday" "12" "February" "2001" "13:27:21" "-0800" "N. Lindberg" "nlindber@u.washington.edu" nil "45" "Re: starship-design: Thoughts on antimatter and fusion..." "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 2098 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1CLRUt07537 for starship-design-outgoing; Mon, 12 Feb 2001 13:27:30 -0800 (PST) Received: from jason02.u.washington.edu (root@jason02.u.washington.edu [140.142.8.52]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1CLRSQ07522 for ; Mon, 12 Feb 2001 13:27:28 -0800 (PST) Received: from dante40.u.washington.edu (nlindber@dante40.u.washington.edu [140.142.15.200]) by jason02.u.washington.edu (8.9.3+UW00.05/8.9.3+UW00.12) with ESMTP id NAA52862; Mon, 12 Feb 2001 13:27:21 -0800 Received: from localhost (nlindber@localhost) by dante40.u.washington.edu (8.9.3+UW00.05/8.9.3+UW00.12) with ESMTP id NAA39508; Mon, 12 Feb 2001 13:27:21 -0800 In-Reply-To: <000a01c094eb$9add6580$4d3a3cd0@nless> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Precedence: bulk Reply-To: "N. Lindberg" From: "N. Lindberg" Sender: owner-starship-design@lists.uoregon.edu To: Johnny Thunderbird cc: "L. Parker" , "Starship-Design (E-mail)" Subject: Re: starship-design: Thoughts on antimatter and fusion... Date: Mon, 12 Feb 2001 13:27:21 -0800 (PST) Johnny, Ion accelerators (linacs, cyclotrons, betatrons, etc.) are usually quite inefficient. For example, last year i worked at a high current vandegraff tandem that ran at 10's of MeV, and 10's of nA (so beam power about .1 watt) - would anyone like to guess how much power it took to run the thing? And the accelerator is the size of a double-wide. Nels On Mon, 12 Feb 2001, Johnny Thunderbird wrote: > > ANY drive that requires reaction mass is inherently unsuited for > > Interstellar space... > > It's unwarranted to dismiss the reaction drive out of hand. That's the only > thing that we know works. We have firm physical expectation that the photon > drive will work, but no concrete reason to believe it preferable to > rocketry. We can also expect that acceleration may be available from > crossing magnetic lines of force, which are demonstrably present in > interstellar space, for electric motors work that way. However, no net > impetus is attained parallel to such lines of force. Electromagnetic drives > won't get you much of anywhere. These three possibilities exhaust the > physically demonstrated principles for space drives, and beyond these lies > ectoplasmic vaporware. > > I feel it's presumptuous to reject rocketry for the flashlight drive, when > no one has a clue how the photons might be generated. Respondents here favor > the (near) perfect conversion of mass to energy; so do we all. Until we know > how to perfectly transduce one form of energy into another, say electricity > into light, this is not even theorizing, just wishful thinking. I'd like to > get some engineering done, show us the iron. OK, a resistance heater will > perfectly transform electrical energy into (mostly infrared) light, but this > has a blackbody spectrum, can't be collimated, so makes a lousy drive. > > I think what I proposed last year, a relativistic linear accelerator for a > reaction drive, will equal or beat (in terms of efficiency) any specific > proposal you can produce for a drive based on photons generated onboard the > ship. > > Johnny Thunderbird > > From VM Tue Feb 13 10:25:59 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["3066" "Monday" "12" "February" "2001" "21:17:57" "-0600" "Johnny Thunderbird" "jthunderbird@nternet.com" nil "55" "starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 3066 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1D4EkQ06447 for starship-design-outgoing; Mon, 12 Feb 2001 20:14:46 -0800 (PST) Received: from eagle.nternet.com (eagle.nternet.com [208.60.58.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with SMTP id f1D4EiQ06416 for ; Mon, 12 Feb 2001 20:14:44 -0800 (PST) Received: (qmail 22299 invoked from network); 13 Feb 2001 04:13:29 -0000 Received: from unknown (HELO nless) (208.60.58.86) by eagle.nternet.com with SMTP; 13 Feb 2001 04:13:29 -0000 Message-ID: <000901c0956b$90e15660$563a3cd0@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "Johnny Thunderbird" From: "Johnny Thunderbird" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: starship-design: LINAC efficiency Date: Mon, 12 Feb 2001 21:17:57 -0600 Nels said these machines are usually quite inefficient, but did not say that these machines must be constrained to be quite inefficient in the general case. Of course, they are not, for their efficiency limitations are aspects of their engineering rather than fundamental physical restrictions. The efficiency problems connected with accelerators are engineering issues, while laser efficiency is inherently limited by material characteristics. An accelerator device has never been designed as a main mover, for all large accelerators currently are built as instruments to investigate other aspects of physics. An accelerator purpose built for a spaceship engine could eliminate ohmic losses by use of superconductors throughout. Since it would be made for continuous operation, the losses associated with the run up of power levels would not be a factor. Since it would be made for operation at a constant power level, and thus at a single excitation frequency, none of the losses in inductive and capacitative elements need be tolerated, for resonant cavities could be used as the frequency determining component. Needless to say, the pump down cycle would not drain any power, for the best vacuum you could ask for is all around it in space! Of course, Van de Graaf and Wimshurst type high-voltage machines, which comb static electrons off a moving wheel or belt, are not suitable for efficiency comparisons. Frictional forces and wear involving moving parts should not be a feature of spaceship drive components. In general, moving streams of plasma manipulated only by electromagnetic forces, without any contact with solid structural elements, offer extraordinary opportunities for engineering optimizations. In contrast, the monochromatic light sources available to us have no comparable possibilities, because they are explicitly bounded by the physical characteristics of the material of which they are composed. Efficiencies exceeding 50% are doubtful for solid state lasers, though quantum discoveries continually surprise us. With waveguides propagating a constant excitation frequency to alternating linac segments, and the entire structure attuned to the fundamental frequency, there would be every reason to hope for a 99%+ electrical efficiency measured against ohmic losses. Waveguide and resonator surfaces could universally be of superconducting material, built to tuned dimensions. We could hope to make this machine firing off protons, among the most efficient machines we will ever be able to built. (And a good thing, too, since it might be among the biggest and costliest machines we'll build for a long, long time...) Johnny Thunderbird Nels Lindgren wrote: ------- Johnny, Ion accelerators (linacs, cyclotrons, betatrons, etc.) are usually quite inefficient. For example, last year i worked at a high current vandegraff tandem that ran at 10's of MeV, and 10's of nA (so beam power about .1 watt) - would anyone like to guess how much power it took to run the thing? And the accelerator is the size of a double-wide. Nels -------- From VM Tue Feb 13 10:25:59 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2708" "Monday" "12" "February" "2001" "23:46:01" "-0600" "Johnny Thunderbird" "jthunderbird@nternet.com" nil "42" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 2708 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1D6gjQ28715 for starship-design-outgoing; Mon, 12 Feb 2001 22:42:45 -0800 (PST) Received: from eagle.nternet.com (eagle.nternet.com [208.60.58.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with SMTP id f1D6ghQ28708 for ; Mon, 12 Feb 2001 22:42:44 -0800 (PST) Received: (qmail 27621 invoked from network); 13 Feb 2001 06:41:33 -0000 Received: from unknown (HELO nless) (208.60.58.94) by eagle.nternet.com with SMTP; 13 Feb 2001 06:41:33 -0000 Message-ID: <001001c09580$3f973300$5e3a3cd0@nless> References: <000901c0956b$90e15660$563a3cd0@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "Johnny Thunderbird" From: "Johnny Thunderbird" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: LINAC efficiency Date: Mon, 12 Feb 2001 23:46:01 -0600 Having a hungry linac may be fun and exciting, but we will need to figure out what to feed it. I favor the ram scoop method pioneered by Bussard. The structural requirement for a current loop meant to serve as a magnet, is that the current carrying conductor, which in all cases should be operating in superconducting mode, need have the mechanical rigidity to resist collapsing into its own magnetic field. Neglecting for the moment any axial components of force, its radial, inwardly-compressive component could be compensated by rotation. The superconducting ring defining the magnetism, can thus be weaker mechanically, than a non-rotating ring which produces a magnetic field of the same strength. That means it can be less massive, so a gracile magnet ring, in place of a more robust ring, can be a durable starship component. This becomes a very desirable feature, when very large scale constructions are considered. Very large scale magnets are useful for ram scoops. As we are all quite aware, none of us want to try designing a starship which carries all its own reaction mass, fuel and energy from launch point. That's one of the things we can agree just won't work. We have to pick up some fuel, and/or some reaction mass, and/or some energy along the way somewhere, somehow. We can get express shipments from our friends back home for some of these things, but it seems to me best, not to count on home base assistance for more the first fraction of the journey. After that, we will need a way to live off the land, so to speak, even though interstellar space offers really sparse pickings. Since we know a way to make gracile magnet rings real big, we can push them along in front of the ship with radiation pressure from lasers. The interstellar plasma, with a partial pressure I expect to be about one proton/electron pair per cubic centimeter, will be concentrated by this magnetism into a brisk refreshing breeze on the ship's bow. Hopefully neutral atoms will also be ducted in to us by the winds stirred up by our magnets. This is the time to introduce our our mass spectrometry, by which we can magnetically deflect the electrons and ions away from the neutrally charged interstellar gas. This gas we ionize, and merge it with the ion and electron streams, flowing so swiftly by. Carefully separating the protons from the ions which astronomers call "metals", we duct the protons into our linac, to be booted out the business end, at relativistic velocity, as reaction mass. The remaining ions are mined for lithium, to feed our fusion reactor. (I mentioned proton-lithium fusion in a post last week.) Anything heavier, we keep with us in case it might be useful. Johnny Thunderbird From VM Tue Feb 13 10:25:59 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2821" "Monday" "12" "February" "2001" "23:32:51" "-0800" "Steve VanDevender" "stevev@efn.org" nil "47" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 2821 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1D7XVn15665 for starship-design-outgoing; Mon, 12 Feb 2001 23:33:31 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1D7XSQ15652 for ; Mon, 12 Feb 2001 23:33:28 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f1D7XMC01135 for ; Mon, 12 Feb 2001 23:33:22 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f1D7XBA07394; Mon, 12 Feb 2001 23:33:11 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <14984.58147.354637.729830@tzadkiel.efn.org> In-Reply-To: <001001c09580$3f973300$5e3a3cd0@nless> References: <000901c0956b$90e15660$563a3cd0@nless> <001001c09580$3f973300$5e3a3cd0@nless> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: LINAC efficiency Date: Mon, 12 Feb 2001 23:32:51 -0800 Johnny Thunderbird writes: > Having a hungry linac may be fun and exciting, but we will need to figure > out what to feed it. I favor the ram scoop method pioneered by Bussard. There's a problem with ramscoops. Yes, you can sweep up interstellar hydrogen and fuse it for thrust. But once your ship is at speed, sweeping up that hydrogen induces drag. If you're trying to put that hydrogen into a fusion reactor, you have to bring it up to the speed of the ship to get it in there; eventually, the thrust you get from the hydrogen only matches the drag of the ramscoop. In the case where you have to bring the hydrogen fully up to the speed of the ship before you fuse and expel it, it's expected that the ship will top out at about 0.1 c. The incoming stream of hydrogen moving at 0.1 c relative to your ship is exactly balanced by an equal mass of outgoing fusion products moving at 0.1 c. At that point you may as well shut down the ramscoop and coast. It's not physically impossible that you might be able to use a ramscoop to gather hydrogen and "pinch" it into a concentrated stream without slowing it down appreciably, and then induce it to fuse, _and_ then be able to get the fusion exhaust to interact with the ship such that it actually induces thrust. That might be able to squeeze a couple more tenths of a c more out of a ramscoop drive, but the problem of confining and inducing fusion in a relativistic stream of hydrogen is non-trivial. I can see how Lee would be tempted by the idea of "reactionless" drives, but conservation of momentum and energy seem to be rather fundamental to physics as we know it, and probably even as we don't yet know it. Most likely a "reactionless" drive would just produce some exotic reaction product; Larry Niven's fictional reactionless drive that turns energy into a coherent stream of neutrinos, or other hypothetical drives that produced photons or gravity waves (which also carry momentum) would really still be reaction drives. Also, no matter what drive you use, in order to get to high relativistic speeds you need some extremely copious source of energy, whether it be a huge mass of hydrogen or a smaller, but still quite impressive, quantity of matter and antimatter. Getting a ship up to 0.7 c or so requires about as much energy as would be obtained by converting an amount of mass equal to the ship's own mass entirely to energy. That's why interstellar travel at high relativistic speeds is currently considered to be a big problem. No matter what your drive system, you need quite a bit more fuel than ship -- and if your power source is as relatively inefficient (compared to the ideal of total mass-energy conversion) as fusion, you need a _lot_ more fuel and reaction mass than final payload mass, on the order of a million-to-one ratio. From VM Tue Feb 13 16:05:33 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["382" "Tuesday" "13" "February" "2001" "18:59:45" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "8" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 382 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1E006018137 for starship-design-outgoing; Tue, 13 Feb 2001 16:00:06 -0800 (PST) Received: from imo-r08.mx.aol.com (imo-r08.mx.aol.com [152.163.225.8]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1E004Q18105 for ; Tue, 13 Feb 2001 16:00:04 -0800 (PST) Received: from KellySt@aol.com by imo-r08.mx.aol.com (mail_out_v29.5.) id z.41.758b95b (24896) for ; Tue, 13 Feb 2001 18:59:45 -0500 (EST) Message-ID: <41.758b95b.27bb2471@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: LINAC efficiency Date: Tue, 13 Feb 2001 18:59:45 EST In a message dated 2/13/01 12:44:06 AM, jthunderbird@nternet.com writes: >Having a hungry linac may be fun and exciting, but we will need to figure >out what to feed it. I favor the ram scoop method pioneered by Bussard. I think we figured out that their was so little mass out there to scoop, that you really couldn't scoop up more mass then the weight of the scoop equipment. From VM Wed Feb 14 14:34:17 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1525" "Wednesday" "14" "February" "2001" "16:11:17" "-0600" "L. Parker" "lparker@cacaphony.net" nil "32" "RE: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1525 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1EMN6T17599 for starship-design-outgoing; Wed, 14 Feb 2001 14:23:06 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1EMN3Q17582 for ; Wed, 14 Feb 2001 14:23:04 -0800 (PST) Received: from broadsword (p474.gnt.com [204.49.91.90]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id QAA08170; Wed, 14 Feb 2001 16:23:02 -0600 Message-ID: <009901c096d4$8fecfc40$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 In-Reply-To: <14984.58147.354637.729830@tzadkiel.efn.org> Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "'Steve VanDevender'" , Subject: RE: starship-design: LINAC efficiency Date: Wed, 14 Feb 2001 16:11:17 -0600 > There's a problem with ramscoops. Yes, you can sweep up interstellar > hydrogen and fuse it for thrust. But once your ship is at speed, > sweeping up that hydrogen induces drag. If you're trying to put that > hydrogen into a fusion reactor, you have to bring it up to > the speed of > the ship to get it in there; eventually, the thrust you get from the > hydrogen only matches the drag of the ramscoop. > ......(clip) Steve puts it rather succinctly, for more in-depth treatment try NASA's website "Warp Drive When?" by Marc Millis. There are some excellent PowerPoint slides there that illustrate the mass vs. velocity problem as well as the basis for Marc's reasoning that reaction drives, although useful at the moment, just won't cut it for long term interstellar travel. I would like to clarify a term however. What I meant by reaction drive is a classical rocket - whether it is chemical, nuclear, fusion or antimatter is irrelevant - they are all rockets. By "reactionless" I actually meant REACTANTLESS, a slightly different animal. Carrying propellant, as Steve points out, is a terrible drag as is trying to scoop it out of space. Ideally, we would discover two things: 1) A source of propulsive energy extraneous to the ship, 2) A method of nullifying the effects of inertia These two things alone would make interstellar travel possible in "real-time", i.e. Alpha Centauri would only be 4 years away, not fifty. Warp drive, worm holes and hyper space, although nice, are not absolutely necessary. Lee From VM Wed Feb 14 15:03:18 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2484" "Wednesday" "14" "February" "2001" "16:45:50" "-0600" "L. Parker" "lparker@cacaphony.net" nil "64" "starship-design: FW: SSRT: Qualification testing on X-33 flight engines" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 2484 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1EMrsD06004 for starship-design-outgoing; Wed, 14 Feb 2001 14:53:54 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1EMrpQ05990 for ; Wed, 14 Feb 2001 14:53:52 -0800 (PST) Received: from broadsword (p474.gnt.com [204.49.91.90]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id QAA17171 for ; Wed, 14 Feb 2001 16:53:55 -0600 Message-ID: <009b01c096d8$de6cd2b0$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "Starship-Design \(E-mail\)" Subject: starship-design: FW: SSRT: Qualification testing on X-33 flight engines Date: Wed, 14 Feb 2001 16:45:50 -0600 -----Original Message----- From: listserv@ds.cc.utexas.edu [mailto:listserv@ds.cc.utexas.edu]On Behalf Of Chris W. Johnson Sent: Friday, February 09, 2001 1:33 PM To: Single Stage Rocket Technology News Subject: SSRT: Qualification testing on X-33 flight engines From : For Release: Feb. 7, 2001 Release: 01-051 Qualification testing on X-33 flight engines now underway at Stennis Space Center, Miss. Qualification test firings of the unique engines designed to propel America's X-33 space plane into high-speed, suborbital flight in 2003 began Tuesday at NASA's John C. Stennis Space Center in Bay St. Louis, Miss. The ignition test went the full scheduled duration of 1.1 seconds with no observed anomalies. Initial tandem test firings of the XRS-2200 Linear Aerospike engines will be short bursts such as this, eventually leading to durations required to send the unpiloted vehicle from a launch pad in California to landings in either Utah or Montana. The engines will power the X-33, a half-scale, sub-orbital flight demonstrator of technology required for a reusable launch vehicle. "Initial indications are all test objectives were met in this first test of the flight engines," said Mike McKeon, program manager for the XRS-2200 aerospike engine at the Rocketdyne Propulsion & Power business of The Boeing Company. "We are now reviewing the data and preparing to move into longer duration testing." "I'm excited about beginning this phase of testing," said Dr. Don Chenevert, NASA's X-33 project manager at Stennis. "I'm confident the remainder of dual-engine testing will perform equally as well as this initial ignition test." Eight more test firings of the twin flight engines are planned at Stennis before they are delivered to Lockheed Martin's X-33 assembly facility in Palmdale, Calif. Fourteen single-engine test firings of a development configuration of the unique Aerospike engine were successfully completed at Stennis Space Center in May 2000. Boeing Rocketdyne developed the XRS-2200 Aerospike engine at its Canoga Park, Calif., facility. Final engine assembly was done by the NASA/Boeing Rocketdyne team at Stennis Space Center. The X-33 project is being developed under a cooperative agreement between NASA and Lockheed Martin Space Systems Company, Denver, Colo. Marshall Space Flight Center in Huntsville, Ala., manages the X-33 program for NASA. From VM Thu Feb 15 10:12:02 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["4332" "Thursday" "15" "February" "2001" "10:40:01" "-0600" "Johnny Thunderbird" "jthunderbird@nternet.com" nil "76" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 4332 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1FHaUn29510 for starship-design-outgoing; Thu, 15 Feb 2001 09:36:30 -0800 (PST) Received: from eagle.nternet.com (eagle.nternet.com [208.60.58.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with SMTP id f1FHaSQ29503 for ; Thu, 15 Feb 2001 09:36:29 -0800 (PST) Received: (qmail 12373 invoked from network); 15 Feb 2001 17:35:14 -0000 Received: from unknown (HELO nless) (208.60.58.71) by eagle.nternet.com with SMTP; 15 Feb 2001 17:35:14 -0000 Message-ID: <001001c0976d$f1cac0c0$473a3cd0@nless> References: <000901c0956b$90e15660$563a3cd0@nless><001001c09580$3f973300$5e3a3cd0@nless> <14984.58147.354637.729830@tzadkiel.efn.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "Johnny Thunderbird" From: "Johnny Thunderbird" Sender: owner-starship-design@lists.uoregon.edu To: Subject: Re: starship-design: LINAC efficiency Date: Thu, 15 Feb 2001 10:40:01 -0600 Steve, your objection (although it is of course relevant) is directed to Bussard's concept of using a fusion drive with ramscoop material. Though I have spoken of using proton-lithium fusion, for a drive it only suffices "in system", because its exhaust particles do not achieve relativistic velocity. I do not intend to use fusion rocketry for the main legs of a starship, but as an onboard power source, so this makes its propulsion efficiency irrelevant. For the legs, one uses a tuned linac, as I specified. This makes some of the objections moot, for with an accelerator drive you are putting out relativistic particles, meaning you can achieve an arbitrary thrust from a small amount of reaction mass, if you have the energy to do so. That someone is dissatisfied with fusion efficiency, is no reason not to have a fusion power reactor aboard the ship. Clearly, it is better to have a working fusion power reactor aboard, than not to have one. People might have theories about other power sources, but wishes are not horses. When they show me something that works, we might be talking engineering. Call the propulsion portion covered, for no one has a motive system giving greater efficiency, than I believe electrical acceleration of particles to near lightspeed can be. The question remains, how to provide the electrical energy to power this drive. Nuclear fusion is the most obvious answer. I have advocated using stored energy as well, in motor-generator flywheel devices of overstressed iron rings, spinning in toroidal superconducting solenoids. Quibbling over the theoretical limitations of nuclear fusion is not productive, for the components making up the fuel for the fusion reactor are continuously being gleaned from the ambient surroundings. If the fusion reaction is not efficient enough for your tastes, just make it bigger. There is lots of hydrogen out there, and within it is a teeny taste of lithium, so this energy is not metered. You can indeed feed your fusion reactor with the mass equivalent of your starship, dozens of times over, so in effect there is no practical limit to the amount of energy you can generate by fusion, when you are not required to carry its fuel components. The important modification, that this fusion energy is diverted to a highly efficient accelerator to comprise your drive, rather than being expended (thermally) in a fruitless attempt to speed up the fusion products themselves, for reaction mass, makes a world of difference in the basis of your calculations. Your point on drag is well taken. It clearly must be considered, in considering designs using ramscoops. Perhaps a partial answer would lie in reducing the ram cross section, during the critical acceleration phase just before turnover. This is when the most nearly relativistic ship velocity is needed, and you would want your highest acceleration capability at this time. At this juncture, you might shut down the fusion reactor altogether, to eliminate its demand for mass throughput, and run on your stored power. You would keep just enough ram scoop area showing, during this final boost before turnover, to feed the linac. After turnover, the drag force you mentioned can only assist deceleration, so the greater the ram cross sectional area the better. Johnny Thunderbird >From Steve VanDevender: > Johnny Thunderbird writes: > > Having a hungry linac may be fun and exciting, but we will need to figure > > out what to feed it. I favor the ram scoop method pioneered by Bussard. > > There's a problem with ramscoops. Yes, you can sweep up interstellar > hydrogen and fuse it for thrust. But once your ship is at speed, > sweeping up that hydrogen induces drag. If you're trying to put that > hydrogen into a fusion reactor, you have to bring it up to the speed of > the ship to get it in there; eventually, the thrust you get from the > hydrogen only matches the drag of the ramscoop. > > In the case where you have to bring the hydrogen fully up to the speed > of the ship before you fuse and expel it, it's expected that the ship > will top out at about 0.1 c. The incoming stream of hydrogen moving at > 0.1 c relative to your ship is exactly balanced by an equal mass of > outgoing fusion products moving at 0.1 c. At that point you may as well > shut down the ramscoop and coast. From VM Thu Feb 15 12:27:02 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["3739" "Thursday" "15" "February" "2001" "12:38:54" "-0600" "Johnny Thunderbird" "jthunderbird@nternet.com" nil "65" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 3739 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1FJZOU11340 for starship-design-outgoing; Thu, 15 Feb 2001 11:35:24 -0800 (PST) Received: from eagle.nternet.com (eagle.nternet.com [208.60.58.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with SMTP id f1FJZMQ11193 for ; Thu, 15 Feb 2001 11:35:22 -0800 (PST) Received: (qmail 17878 invoked from network); 15 Feb 2001 19:34:08 -0000 Received: from unknown (HELO nless) (208.60.58.111) by eagle.nternet.com with SMTP; 15 Feb 2001 19:34:08 -0000 Message-ID: <002401c0977e$8d335940$473a3cd0@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "Johnny Thunderbird" From: "Johnny Thunderbird" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: LINAC efficiency Date: Thu, 15 Feb 2001 12:38:54 -0600 Roy Bennett writes: Hello, I am new ish to the list and have not posted before so forgive me if there's anything wrong with this post. I assume that by 'turnover' you mean the point at which the ship turns round in order to decellerate. If this is the case your ram scoop will be pretty useless as it's facing backwards. How can a ram scoop ship decellerate? :) Roy All the starship voyages that I like are all just about the same, because they all take about two and a half years one way, as it seems to you anyway. The way this works out, is that you fiddle around in the system for a couple of months, and then you boost outward for one year. It takes one year, at one gravity acceleration, to get within a gnat's ass of C, which is 300,000 kliks per second. At that time, you want to hop around like a little bunny, time's a-wasting, get that ship cranked around quick as you possibly can, so you can start slowing down. Your time slippage is radical. The ratio of your time dilation factor to clocks back home, is something you don't want to think about, lucky thing you're so busy. When you have your proper weight again at 1 g, your destination star system is straight down under your feet, and the home you came from is straight up over your head. You will have one year of slowing down to do, and then a few months fiddling around in the system, before you can hop off your ride. Starship journeys are all alike. When they're done right, that is. If you you do them wrong, they can get to be a real drag. Starship journeys done right, at a constant 1 g boost to turnover, then a constant 1 g boost (the other way) to destination, will all take just about the same amount of subjective ship time, whether you are going 4 light years or 400 light years. That's because the real traveling you're doing, is mostly done during that hectic period near the turn around, while time in the stationary universe goes whizzing by too fast for you to notice it. Rocket jockeys, people used to solar system dynamics, get the horrors when you ask them for a constant 1 g boost. Nobody's that rich, they say. We starship designers shrug, and tell them that's what we have to have; they asked us what we needed to get the job done, and we told them. You can either do it the right way, or you can do it any old way you want, because it doesn't matter. The difference is, if you do it the right way, you can get there and back, otherwise not. When you're slowing down, your ramscoop is gathering in stuff from ahead of the ship, just like it was in boost phase. The difference is, your jet is also firing off in the same direction. Design-wise, you have to turn around that stiff breeze your scoop hauls in. It's made of cosmic rays, or you might as well call it that, because when you begin slowing down that stiff breeze is whistling in at awfully close to lightspeed. You don't want to let the ions blow on anything solid, because it gets eroded fast. The only way you can turn them is with magnets, so you curl them around into your drive and blow them all out ahead of you. This has the useful effect of ionizing everything you're going to run into. What you don't want to deal with, is neutral atoms coming that fast, because neutral winds can't be turned with magnets. My version of the ram scoop, you may notice, is not attatched to the ship by material structures. It floats out ahead of the ship a ways, consisting of thin rings pushed out there by light pressure from lasers, as I said, or pushed out there by neutral beams, as I didn't say. These don't have to be turned around, but the rest of the ship does. My LINAC is going to be long, and it bothers me to have to turn it around, especially in a hurry. Johnny Thunderbird From VM Thu Feb 15 12:58:57 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1646" "Thursday" "15" "February" "2001" "12:47:05" "-0800" "Steve VanDevender" "stevev@efn.org" nil "25" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1646 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1FKlMc25195 for starship-design-outgoing; Thu, 15 Feb 2001 12:47:22 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1FKlKQ25170 for ; Thu, 15 Feb 2001 12:47:20 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f1FKlHC04851; Thu, 15 Feb 2001 12:47:17 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f1FKl6Q16949; Thu, 15 Feb 2001 12:47:06 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <14988.16457.384927.288560@tzadkiel.efn.org> In-Reply-To: <001001c0976d$f1cac0c0$473a3cd0@nless> References: <000901c0956b$90e15660$563a3cd0@nless> <001001c09580$3f973300$5e3a3cd0@nless> <14984.58147.354637.729830@tzadkiel.efn.org> <001001c0976d$f1cac0c0$473a3cd0@nless> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "Johnny Thunderbird" Cc: Subject: Re: starship-design: LINAC efficiency Date: Thu, 15 Feb 2001 12:47:05 -0800 Johnny Thunderbird writes: > Steve, your objection (although it is of course relevant) is directed to > Bussard's concept of using a fusion drive with ramscoop material. Though I > have spoken of using proton-lithium fusion, for a drive it only suffices "in > system", because its exhaust particles do not achieve relativistic velocity. > I do not intend to use fusion rocketry for the main legs of a starship, but > as an onboard power source, so this makes its propulsion efficiency > irrelevant. For the legs, one uses a tuned linac, as I specified. This makes > some of the objections moot, for with an accelerator drive you are putting > out relativistic particles, meaning you can achieve an arbitrary thrust from > a small amount of reaction mass, if you have the energy to do so. > > That someone is dissatisfied with fusion efficiency, is no reason not to > have a fusion power reactor aboard the ship. Clearly, it is better to have a > working fusion power reactor aboard, than not to have one. People might have > theories about other power sources, but wishes are not horses. When they > show me something that works, we might be talking engineering. Think about this more carefully. You have to get more energy to obtain that "arbitrary thrust"; that means that you have to gather more hydrogen with your ramscoop, fuse it, then concentrate that energy into a smaller amount of reaction mass. But by gathering that larger quantity of hydrogen, you've just induced more drag on your ship. This extra drag ends up counteracting whatever benefit you hoped to get by producing a higher-velocity, lower-mass exhaust. From VM Thu Feb 15 16:13:39 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1191" "Thursday" "15" "February" "2001" "19:03:05" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "45" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1191 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1G03Ok17111 for starship-design-outgoing; Thu, 15 Feb 2001 16:03:24 -0800 (PST) Received: from imo-r06.mx.aol.com (imo-r06.mx.aol.com [152.163.225.6]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1G03MQ17085 for ; Thu, 15 Feb 2001 16:03:23 -0800 (PST) Received: from KellySt@aol.com by imo-r06.mx.aol.com (mail_out_v29.5.) id r.91.6f1096d (4401); Thu, 15 Feb 2001 19:03:05 -0500 (EST) Message-ID: <91.6f1096d.27bdc839@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: jthunderbird@nternet.com, starship-design@lists.uoregon.edu Subject: Re: starship-design: LINAC efficiency Date: Thu, 15 Feb 2001 19:03:05 EST >Starship journeys done right, at a constant 1 g boost to turnover, then >a > >constant 1 g boost (the other way) to destination, will all take just about > >the same amount of subjective ship time, whether you are going 4 light >years > >or 400 light years. That's because the real traveling you're doing, is > >mostly done during that hectic period near the turn around, while time >in > >the stationary universe goes whizzing by too fast for you to notice it. Of course we haven't even any theoretical idea on how to build a sustain 1G thrust for months at a time. So your ideas mear fantasy. Might as well talk about faster then light drives. > > >My version of the ram scoop, you may notice, is not attatched to the ship >by > >material structures. It floats out ahead of the ship a ways, consisting >of > >thin rings pushed out there by light pressure from lasers, as I said, or > >pushed out there by neutral beams, as I didn't say. These don't have to >be > >turned around, but the rest of the ship does. My LINAC is going to be long, > >and it bothers me to have to turn it around, especially in a hurry. How do you push, and even more difficult - pull them at 1 g? From VM Thu Feb 15 16:13:39 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1872" "Thursday" "15" "February" "2001" "19:03:07" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "43" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1872 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1G03bA17176 for starship-design-outgoing; Thu, 15 Feb 2001 16:03:37 -0800 (PST) Received: from imo-r06.mx.aol.com (imo-r06.mx.aol.com [152.163.225.6]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1G03ZQ17155 for ; Thu, 15 Feb 2001 16:03:35 -0800 (PST) Received: from KellySt@aol.com by imo-r06.mx.aol.com (mail_out_v29.5.) id s.53.26f8901 (4401); Thu, 15 Feb 2001 19:03:07 -0500 (EST) Message-ID: <53.26f8901.27bdc83b@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: stevev@efn.org, jthunderbird@nternet.com CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: LINAC efficiency Date: Thu, 15 Feb 2001 19:03:07 EST In a message dated 2/15/01 2:48:54 PM, stevev@efn.org writes: >Johnny Thunderbird writes: > > Steve, your objection (although it is of course relevant) is directed >to > > Bussard's concept of using a fusion drive with ramscoop material. Though >I > > have spoken of using proton-lithium fusion, for a drive it only suffices >"in > > system", because its exhaust particles do not achieve relativistic velocity. > > I do not intend to use fusion rocketry for the main legs of a starship, >but > > as an onboard power source, so this makes its propulsion efficiency > > irrelevant. For the legs, one uses a tuned linac, as I specified. This >makes > > some of the objections moot, for with an accelerator drive you are putting > > out relativistic particles, meaning you can achieve an arbitrary thrust >from > > a small amount of reaction mass, if you have the energy to do so. > > > > That someone is dissatisfied with fusion efficiency, is no reason not >to > > have a fusion power reactor aboard the ship. Clearly, it is better to >have a > > working fusion power reactor aboard, than not to have one. People might >have > > theories about other power sources, but wishes are not horses. When >they > > show me something that works, we might be talking engineering. > >Think about this more carefully. You have to get more energy to obtain >that "arbitrary thrust"; that means that you have to gather more >hydrogen with your ramscoop, fuse it, then concentrate that energy into >a smaller amount of reaction mass. But by gathering that larger >quantity of hydrogen, you've just induced more drag on your ship. This >extra drag ends up counteracting whatever benefit you hoped to get by >producing a higher-velocity, lower-mass exhaust. And again, our analysis here was that you couldn't scoop up as much mass as the mass of the scoop over any nearby mission. From VM Thu Feb 15 16:28:46 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["651" "Wednesday" "14" "February" "2001" "02:32:37" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "14" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 651 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1G0O4G29370 for starship-design-outgoing; Thu, 15 Feb 2001 16:24:04 -0800 (PST) Received: from main.jetnet.ab.ca (root@jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1G0NvQ29335 for ; Thu, 15 Feb 2001 16:23:58 -0800 (PST) Received: from jetnet.ab.ca (dialin55.jetnet.ab.ca [207.153.6.55]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id RAA15064 for ; Thu, 15 Feb 2001 17:14:11 -0700 (MST) Message-ID: <3A8A50B5.69C10DB8@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: <91.6f1096d.27bdc839@aol.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: LINAC efficiency Date: Wed, 14 Feb 2001 02:32:37 -0700 KellySt@aol.com wrote: > Of course we haven't even any theoretical idea on how to build a sustain 1G > thrust for months at a time. So your ideas mear fantasy. Might as well talk > about faster then light drives. Good point - any ideas on using faster light? I am thinking of the experiments that claim to have light traveling 300C in Cesium. >turned around, but the rest of the ship does. My LINAC is going to be long, Can't you reverse the magnets? Then in becomes out. -- "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk From VM Thu Feb 15 16:44:54 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["748" "Thursday" "15" "February" "2001" "16:37:39" "-0800" "Steve VanDevender" "stevev@efn.org" nil "15" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 748 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1G0c4W06983 for starship-design-outgoing; Thu, 15 Feb 2001 16:38:04 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1G0c1Q06973 for ; Thu, 15 Feb 2001 16:38:01 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f1G0bvC20915 for ; Thu, 15 Feb 2001 16:37:57 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f1G0bkd17377; Thu, 15 Feb 2001 16:37:46 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <14988.30291.516081.791684@tzadkiel.efn.org> In-Reply-To: <53.26f8901.27bdc83b@aol.com> References: <53.26f8901.27bdc83b@aol.com> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: LINAC efficiency Date: Thu, 15 Feb 2001 16:37:39 -0800 KellySt@aol.com writes: > And again, our analysis here was that you couldn't scoop up as much mass as > the mass of the scoop over any nearby mission. You would need a large scoop cross-section, but it's not inconceivable. Let's say your scoop can pick up on average 1 hydrogen atom per cubic centimeter. Over a distance of 4.3 light years, you can pick up about 7 * 10^-5 kilograms of hydrogen per square meter of scoop area. So to pick up 10^9 kg of hydrogen during that trip, for example, you'd need a scoop with an area of 1.5 * 10^13 m^2, or some 2000 km in radius. This is all just back-of-the-envelope calculation, of course, but it's clearly an indication that you'd need a very large ramscoop to make a reasonably-sized ship work. From VM Thu Feb 15 20:49:48 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["524" "Thursday" "15" "February" "2001" "21:55:15" "-0600" "L. Parker" "lparker@cacaphony.net" nil "13" "RE: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 524 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1G4k1A16959 for starship-design-outgoing; Thu, 15 Feb 2001 20:46:01 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1G4jxQ16950 for ; Thu, 15 Feb 2001 20:45:59 -0800 (PST) Received: from broadsword (p455.gnt.com [204.49.91.71]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id WAA20672; Thu, 15 Feb 2001 22:45:39 -0600 Message-ID: <000701c097d3$2a2e87c0$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) Importance: Normal In-Reply-To: <14988.30291.516081.791684@tzadkiel.efn.org> X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "'Steve VanDevender'" , Subject: RE: starship-design: LINAC efficiency Date: Thu, 15 Feb 2001 21:55:15 -0600 > Let's say your scoop can pick up on average 1 hydrogen atom per cubic > centimeter. Over a distance of 4.3 light years, you can pick > up about 7 > * 10^-5 kilograms of hydrogen per square meter of scoop area. So to > pick up 10^9 kg of hydrogen during that trip, for example, > you'd need a > scoop with an area of 1.5 * 10^13 m^2, or some 2000 km in radius. Did I miss something? I thought the local interstellar medium had been determined to be thinner than once thought - like only 0.1 atom per cubic meter... Lee From VM Mon Feb 19 10:37:37 2001 Content-Length: 767 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["767" "Thursday" "15" "February" "2001" "21:58:13" "-0800" "Steve VanDevender" "stevev@efn.org" nil "18" "RE: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 767 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1G5wor12104 for starship-design-outgoing; Thu, 15 Feb 2001 21:58:50 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1G5wkQ12090 for ; Thu, 15 Feb 2001 21:58:47 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f1G5wfC14431 for ; Thu, 15 Feb 2001 21:58:42 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f1G5wUR17862; Thu, 15 Feb 2001 21:58:30 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <14988.49525.494885.989296@tzadkiel.efn.org> In-Reply-To: <000701c097d3$2a2e87c0$0100a8c0@broadsword> References: <14988.30291.516081.791684@tzadkiel.efn.org> <000701c097d3$2a2e87c0$0100a8c0@broadsword> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: Subject: RE: starship-design: LINAC efficiency Date: Thu, 15 Feb 2001 21:58:13 -0800 L. Parker writes: > > Let's say your scoop can pick up on average 1 hydrogen atom per cubic > > centimeter. Over a distance of 4.3 light years, you can pick > > up about 7 > > * 10^-5 kilograms of hydrogen per square meter of scoop area. So to > > pick up 10^9 kg of hydrogen during that trip, for example, > > you'd need a > > scoop with an area of 1.5 * 10^13 m^2, or some 2000 km in radius. > > Did I miss something? I thought the local interstellar medium had been > determined to be thinner than once thought - like only 0.1 atom per cubic > meter... I have to admit the density figure of 1 atom H per cm^3 came off the top of my head and may be old and inaccurate. If it's 0.1 atom per cubic meter, then yeah, ramscoops will have huge problems. From VM Mon Feb 19 10:37:37 2001 Content-Length: 605 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["605" "Friday" "16" "February" "2001" "12:14:23" "+0100" "Roy Bennett" "roybennett@bigfoot.com" nil "17" "starship-design: LINAC" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 605 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1GBEvV06367 for starship-design-outgoing; Fri, 16 Feb 2001 03:14:57 -0800 (PST) Received: from edfms5.muc.edf.de ([195.127.214.202]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1GBEtQ06357 for ; Fri, 16 Feb 2001 03:14:55 -0800 (PST) Received: from bigfoot.com (edf07.muc.edf.de [172.28.1.7]) by edfms5.muc.edf.de with SMTP (Microsoft Exchange Internet Mail Service Version 5.5.2650.21) id FBKN8CZZ; Fri, 16 Feb 2001 12:15:28 +0100 Message-ID: <3A8D0B8F.8EB21AE7@bigfoot.com> X-Mailer: Mozilla 4.07 [en] (X11; I; AIX 4.3) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Roy Bennett From: Roy Bennett Sender: owner-starship-design@lists.uoregon.edu To: Starship Design List Subject: starship-design: LINAC Date: Fri, 16 Feb 2001 12:14:23 +0100 Johnny Thunderbird wrote: > > All the starship voyages that I like are all just about the same, because > they all take about two and a half years one way, as it seems to you anyway. > The way this works out, is that you fiddle around in the system for a couple > of months, and then you boost outward for one year. It takes one year, at > one gravity acceleration, to get within a gnat's ass of C, Where is the energy going to come from? It would take an enormous amount of energy to accelerate anything with significant mass at 1g for a year! even if you ignore relativistic mass increase. ;-0 Roy From VM Mon Feb 19 10:37:43 2001 Content-Length: 465 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["465" "Saturday" "17" "February" "2001" "00:48:28" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "12" "starship-design: Hi honey, I'm home" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 465 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1H7ipW09974 for starship-design-outgoing; Fri, 16 Feb 2001 23:44:51 -0800 (PST) Received: from mail1.mco.bellsouth.net (mail1.mco.bellsouth.net [205.152.111.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1H7inQ09968 for ; Fri, 16 Feb 2001 23:44:50 -0800 (PST) Received: from nless (host-209-214-157-61.msy.bellsouth.net [209.214.157.61]) by mail1.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id CAA09689 for ; Sat, 17 Feb 2001 02:44:47 -0500 (EST) Message-ID: <004001c098ad$a4dd3ae0$f595fea9@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: Subject: starship-design: Hi honey, I'm home Date: Sat, 17 Feb 2001 00:48:28 -0600 Some mixup trashed out the ISP account at nternet.com which I have used for some years. So I have resubscribed at an alternate email address. Hopefully I can get the mess all straightened out, but it won't be over the weekend for sure. So I have probably missed the last few messages exchanged. That's a shame, because I felt like I was just fixing to get into a good fuss. Fussing is all good clean fun, and it's so refreshing. Respectfully, Johnny Thunderbird From VM Mon Feb 19 10:37:44 2001 Content-Length: 1177 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1177" "Saturday" "17" "February" "2001" "13:28:52" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "26" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1177 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1HITFS09318 for starship-design-outgoing; Sat, 17 Feb 2001 10:29:15 -0800 (PST) Received: from imo-d01.mx.aol.com (imo-d01.mx.aol.com [205.188.157.33]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1HITDQ09312 for ; Sat, 17 Feb 2001 10:29:13 -0800 (PST) Received: from KellySt@aol.com by imo-d01.mx.aol.com (mail_out_v29.5.) id s.8d.2839c7e (3945); Sat, 17 Feb 2001 13:28:52 -0500 (EST) Message-ID: <8d.2839c7e.27c01ce4@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: stevev@efn.org, starship-design@lists.uoregon.edu Subject: Re: starship-design: LINAC efficiency Date: Sat, 17 Feb 2001 13:28:52 EST In a message dated 2/15/01 6:38:56 PM, stevev@efn.org writes: >KellySt@aol.com writes: > > And again, our analysis here was that you couldn't scoop up as much >mass as > > the mass of the scoop over any nearby mission. > >You would need a large scoop cross-section, but it's not inconceivable. > >Let's say your scoop can pick up on average 1 hydrogen atom per cubic >centimeter. Over a distance of 4.3 light years, you can pick up about >7 >* 10^-5 kilograms of hydrogen per square meter of scoop area. So to >pick up 10^9 kg of hydrogen during that trip, for example, you'd need a >scoop with an area of 1.5 * 10^13 m^2, or some 2000 km in radius. > >This is all just back-of-the-envelope calculation, of course, but it's >clearly an indication that you'd need a very large ramscoop to make a >reasonably-sized ship work. And do you really expect the mass of the equipment needed to manage a 2000km ramscoop, projected far enough ahead to scoop in without excessive drag or power loads, and able to hold together at high thrust levels, would weigh less then 10^9 kg? Also this area of the galaxy has significantly less then 1 hydrogen atom per cubic centimeter. From VM Mon Feb 19 10:37:44 2001 Content-Length: 544 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["544" "Saturday" "17" "February" "2001" "13:28:50" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "15" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 544 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1HIT0T09263 for starship-design-outgoing; Sat, 17 Feb 2001 10:29:00 -0800 (PST) Received: from imo-d01.mx.aol.com (imo-d01.mx.aol.com [205.188.157.33]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1HISwQ09255 for ; Sat, 17 Feb 2001 10:28:59 -0800 (PST) Received: from KellySt@aol.com by imo-d01.mx.aol.com (mail_out_v29.5.) id z.7f.10503ab2 (3945) for ; Sat, 17 Feb 2001 13:28:50 -0500 (EST) Message-ID: <7f.10503ab2.27c01ce2@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: LINAC efficiency Date: Sat, 17 Feb 2001 13:28:50 EST In a message dated 2/15/01 6:24:59 PM, bfranchuk@jetnet.ab.ca writes: >> Of course we haven't even any theoretical idea on how to build a sustain >1G >> thrust for months at a time. So your ideas mear fantasy. Might as well >talk >> about faster then light drives. >Good point - any ideas on using faster light? I am thinking of the experiments >that claim to have light traveling 300C in Cesium. That didn't mean what folks think. You might want to look at NASA's "Warp drive when" site. It covers their best guess's at the moment. From VM Mon Feb 19 10:37:44 2001 Content-Length: 738 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["738" "Saturday" "17" "February" "2001" "13:28:53" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "21" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 738 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1HIT4309285 for starship-design-outgoing; Sat, 17 Feb 2001 10:29:04 -0800 (PST) Received: from imo-d01.mx.aol.com (imo-d01.mx.aol.com [205.188.157.33]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1HIT3Q09273 for ; Sat, 17 Feb 2001 10:29:03 -0800 (PST) Received: from KellySt@aol.com by imo-d01.mx.aol.com (mail_out_v29.5.) id z.68.c245032 (3945) for ; Sat, 17 Feb 2001 13:28:54 -0500 (EST) Message-ID: <68.c245032.27c01ce5@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: LINAC efficiency Date: Sat, 17 Feb 2001 13:28:53 EST In a message dated 2/15/01 10:47:13 PM, lparker@cacaphony.net writes: >> Let's say your scoop can pick up on average 1 hydrogen atom per cubic >> centimeter. Over a distance of 4.3 light years, you can pick >> up about 7 >> * 10^-5 kilograms of hydrogen per square meter of scoop area. So to >> pick up 10^9 kg of hydrogen during that trip, for example, >> you'd need a >> scoop with an area of 1.5 * 10^13 m^2, or some 2000 km in radius. > >Did I miss something? I thought the local interstellar medium had been >determined to be thinner than once thought - like only 0.1 atom per cubic >meter... > >Lee Yup, recent supernova in the area cleaned out the area. The formal name is something lige a local bubble or something. Kelly From VM Mon Feb 19 10:37:46 2001 Content-Length: 1480 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1480" "Saturday" "17" "February" "2001" "19:10:24" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "42" "starship-design: Fwd: What the hell was that NASA hoax thing!!!!" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1480 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1I0Dh402428 for starship-design-outgoing; Sat, 17 Feb 2001 16:13:43 -0800 (PST) Received: from imo-r16.mx.aol.com (imo-r16.mx.aol.com [152.163.225.70]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1I0DfQ02416 for ; Sat, 17 Feb 2001 16:13:41 -0800 (PST) Received: from KellySt@aol.com by imo-r16.mx.aol.com (mail_out_v29.5.) id n.fc.27b173d (16492); Sat, 17 Feb 2001 19:10:24 -0500 (EST) Message-ID: MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="part1_fc.27b173d.27c06cf0_boundary" X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: Kryswalker@aol.com, DTaylor648@aol.com, JohnFrance@aol.com, moschleg@erols.com, SFnoirSD@aol.com, alford@netcom.com, bbbark@surfree.com, ASARO@stars.gsfc.nasa.gov, jcavelos@mindspring.com, DotarSojat@aol.com, rddesign@rddesigns.com, RICKJ@btio.com, Kath2go@yahoo.com, t.dyson2@genie.geis.com, Michnavi@aol.com, millahnna@yahoo.com, lparker@cacaphony.net, edrataj@earthlink.net, alwermter@netzero.net, starship-design@lists.uoregon.edu Subject: starship-design: Fwd: What the hell was that NASA hoax thing!!!! Date: Sat, 17 Feb 2001 19:10:24 EST --part1_fc.27b173d.27c06cf0_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In case, like me, you'ld like to write Fox tv a scathing letter about their special "proving" the Apollo program was a hoax askfox@foxinc.com Kelly --part1_fc.27b173d.27c06cf0_boundary Content-Type: message/rfc822 Content-Disposition: inline Return-Path: Received: from rly-yd03.mx.aol.com (rly-yd03.mail.aol.com [172.18.150.3]) by air-yd04.mail.aol.com (v77_r1.21) with ESMTP; Fri, 16 Feb 2001 14:01:53 -0500 Received: from fw01.collins.rockwell.com (gatekeeper.collins.rockwell.com [205.175.225.1]) by rly-yd03.mx.aol.com (v77_r1.21) with ESMTP; Fri, 16 Feb 2001 14:01:30 -0500 Received: by fw01.collins.rockwell.com; id NAA19010; Fri, 16 Feb 2001 13:01:25 -0600 (CST) From: Received: from nodnsquery(131.198.213.32) by fw01.collins.rockwell.com via smap (V5.5) id xmac18775; Fri, 16 Feb 01 13:00:13 -0600 Subject: What the hell was that NASA hoax thing!!!! To: kellyst@aol.com Date: Fri, 16 Feb 2001 12:53:53 -0600 Message-ID: X-MIMETrack: Serialize by Router on CollinsCRSMTP01/CedarRapids/Collins/Rockwell(Release 5.0.6 |December 14, 2000) at 02/16/2001 01:00:14 PM MIME-Version: 1.0 Content-type: text/plain; charset=us-ascii X-Mailer: Unknown (No Version) askfox@foxinc.com --part1_fc.27b173d.27c06cf0_boundary-- From VM Mon Feb 19 10:37:47 2001 Content-Length: 106 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["106" "Saturday" "17" "February" "2001" "20:46:35" "-0500" "Connor Ireland" "chithree@boo.net" nil "2" "Re: starship-design: Fwd: What the hell was that NASA hoax thing!!!!" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 106 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1I1uXc04968 for starship-design-outgoing; Sat, 17 Feb 2001 17:56:33 -0800 (PST) Received: from boo-mda02.boo.net (IDENT:root@boo-mda02.boo.net [216.200.67.22]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1I1uVQ04960 for ; Sat, 17 Feb 2001 17:56:32 -0800 (PST) Received: from 0018514826 (dc-lata-1-13.dynamic-dialup.coretel.net [162.33.62.13]) by boo-mda02.boo.net (8.9.3/8.9.3) with SMTP id UAA29925; Sat, 17 Feb 2001 20:52:59 -0500 Message-ID: <003901c0994c$a32d67c0$0d3e21a2@0018514826> References: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.00.2615.200 X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2615.200 Precedence: bulk Reply-To: "Connor Ireland" From: "Connor Ireland" Sender: owner-starship-design@lists.uoregon.edu To: , , , , , , , , , , , , , , , , , , , , Subject: Re: starship-design: Fwd: What the hell was that NASA hoax thing!!!! Date: Sat, 17 Feb 2001 20:46:35 -0500 My letter was scathing indeed. I told them to "eat me" and wished that they "choke on [their] own vomit." From VM Mon Feb 19 10:22:11 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1493" "Sunday" "18" "February" "2001" "10:08:14" "-0500" "pk" "thida@videotron.ca" nil "41" "RE: starship-design: Fwd: What the hell was that NASA hoax thing!!!!" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1493 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1IF7Im20392 for starship-design-outgoing; Sun, 18 Feb 2001 07:07:18 -0800 (PST) Received: from VL-MS-MR003.sc1.videotron.ca (relais.videotron.ca [24.201.245.36]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1IF7HQ20386 for ; Sun, 18 Feb 2001 07:07:17 -0800 (PST) Received: from ordi1 ([24.201.247.226]) by VL-MS-MR003.sc1.videotron.ca (Netscape Messaging Server 4.15) with SMTP id G8YKL904.PGE; Sun, 18 Feb 2001 10:05:33 -0500 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2314.1300 Importance: Normal Precedence: bulk Reply-To: "pk" From: "pk" Sender: owner-starship-design@lists.uoregon.edu To: , , , , , , , , , , , , , , , , , , , , Subject: RE: starship-design: Fwd: What the hell was that NASA hoax thing!!!! Date: Sun, 18 Feb 2001 10:08:14 -0500 ...Should have sent it to the lsit, but i can't rememebr the address 8) Anyway, does anyone have a point by point summary of what they said?? BC, it'd be easier to rebutt all of their arguments. The only ones i remember are: 1. More than 1 lightsource 2. The flag is moving 3. Same "set" used for different locations. Reasons i see: 1. Earth reflects light too, just like moon. 2. While there is no wind in itself on the moon, there is the solar wind, right? With 1/10 of our gravity and near to no atmosphere, it doesn't have to exert as much pressure 3. In the desert every dune look the same... > -----Original Message----- > From: owner-starship-design@lists.uoregon.edu > [mailto:owner-starship-design@lists.uoregon.edu]On Behalf Of > KellySt@aol.com > Sent: 17 février, 2001 19:10 > To: Kryswalker@aol.com; DTaylor648@aol.com; JohnFrance@aol.com; > moschleg@erols.com; SFnoirSD@aol.com; alford@netcom.com; > bbbark@surfree.com; ASARO@stars.gsfc.nasa.gov; jcavelos@mindspring.com; > DotarSojat@aol.com; rddesign@rddesigns.com; RICKJ@btio.com; > Kath2go@yahoo.com; t.dyson2@genie.geis.com; Michnavi@aol.com; > millahnna@yahoo.com; lparker@cacaphony.net; edrataj@earthlink.net; > alwermter@netzero.net; starship-design@lists.uoregon.edu > Subject: starship-design: Fwd: What the hell was that NASA hoax > thing!!!! > > > > In case, like me, you'ld like to write Fox tv a scathing letter > about their > special "proving" the Apollo program was a hoax > > > askfox@foxinc.com > > > Kelly > From VM Mon Feb 19 10:22:11 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["95" "Monday" "19" "February" "2001" "01:03:13" "-0000" "Daishi" "andrew@hmm.u-net.com" nil "4" "Re: starship-design: Fwd: What the hell was that NASA hoax thing!!!!" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 95 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1J122p12455 for starship-design-outgoing; Sun, 18 Feb 2001 17:02:02 -0800 (PST) Received: from mail1-gui.server.ntli.net (mail1-gui.server.ntli.net [194.168.222.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1J11vQ12435 for ; Sun, 18 Feb 2001 17:01:57 -0800 (PST) Received: from daishi ([62.252.49.166]) by mail1-gui.server.ntli.net (Post.Office MTA v3.1 release PO203a ID# 0-33929U70000L2S50) with SMTP id AAA20187 for ; Mon, 19 Feb 2001 00:55:15 +0000 Message-ID: <002301c09a0f$bc78e380$a631fc3e@daishi> References: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "Daishi" From: "Daishi" Sender: owner-starship-design@lists.uoregon.edu To: Subject: Re: starship-design: Fwd: What the hell was that NASA hoax thing!!!! Date: Mon, 19 Feb 2001 01:03:13 -0000 http://www.badastronomy.com/bad/tv/foxapollo.html has a rebuttal to the whole show. TV Sucks. From VM Mon Feb 19 10:22:11 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["11996" "Sunday" "18" "February" "2001" "19:40:46" "-0600" "L. Parker" "lparker@cacaphony.net" nil "217" "starship-design: A Mass of Inertia (An article about mass and inertia-long)" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 11996 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1J1g5N23018 for starship-design-outgoing; Sun, 18 Feb 2001 17:42:05 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1J1g3Q22997 for ; Sun, 18 Feb 2001 17:42:03 -0800 (PST) Received: from broadsword (p438.gnt.com [204.49.91.54]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id TAA10180 for ; Sun, 18 Feb 2001 19:42:07 -0600 Message-ID: <004301c09a14$ffb43f00$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "Starship-Design \(E-mail\)" Subject: starship-design: A Mass of Inertia (An article about mass and inertia-long) Date: Sun, 18 Feb 2001 19:40:46 -0600 A Mass of Inertia by Marcus Chown London - Feb. 3, 2001 What is this thing called mass? Pondering this apparently simple question, two scientists have come up with a radical theory that could explain the nature of inertia, abolish gravity and, just possibly, lead to bizarre new forms of spacecraft propulsion. Faced with the same question, you might answer that mass is what makes a loaded shopping trolley hard to get moving -- its inertia. Or, perhaps, that mass is what makes a bag of sugar or a grand piano weigh something. Either way, the origin of mass is one of nature's deepest mysteries. Some particle physicists claim that a hypothetical particle called the Higgs boson gives mass to subatomic particles such as electrons. Late last year, hints that the Higgs really exists were found at CERN, the European centre for particle physics near Geneva. So, does the Higgs explain weight and inertia? The answer is probably no. Wait a minute. How can these physicists claim they have discovered the origin of mass when their proposed mechanism fails to explain the very things that make it what it is? Well, as Bill Clinton might say, it all depends on what you mean by mass. When these particle physicists speak of mass, they are not thinking in terms of inertia or weight. Matter is a concentrated form of energy. It can be changed into other forms of energy and other forms of energy can be changed into matter -- an equivalence embodied in Einstein's famous equation E = mc2. So in this sense, the mass of a subatomic particle is a measure of the amount of energy needed to make it. The Higgs can account for that, at least partly (see "Mass delusion", p 25). "But the Higgs mechanism does not explain why mass, or its energy equivalent, resists motion or reacts to gravity," says Bernard Haisch of the California Institute for Physics and Astrophysics in Palo Alto. He believes instead that inertia and gravity are manifestations of far more familiar effects. When you lift that sack of potatoes or shove your shopping trolley, the forces you feel might be plain old electricity and magnetism. If the forces are familiar, their origin is anything but. For in Haisch's view, they come out of the quantum vacuum. What we think of as a vacuum is, according to quantum theory, a sea of force fields. The best understood of all these fields is the electromagnetic field, and it affects us constantly -- our bodies are held together by electromagnetic forces, and light is an oscillation in the electromagnetic field. That these fields pop up in the vacuum is reflected by Heisenberg's uncertainty principle, which states that the shorter the length of time over which an energy measurement is made, the less precise the result will be. So although the energy of the electromagnetic field in the vacuum averages to zero over long periods of time, it fluctuates wildly on very short timescales. Rather than being empty, the vacuum is a choppy sea of randomly fluctuating electromagnetic waves. We don't see or feel them because they pop in and out of existence incredibly quickly, appearing only for a split second. These fleeting apparitions are called virtual photons. But sometimes, virtual becomes real. Stephen Hawking worked out that the powerful gravity of a black hole distorts this quantum sea so much that when a virtual photon appears, it can break free and escape into space, becoming real and visible just like an ordinary photon. And a fundamental principle of Einstein's theory of general relativity is that gravity is indistinguishable from acceleration. So if gravity can release photons from the vacuum, why shouldn't acceleration do the same? In the mid-1970s, Paul Davies at the University of Newcastle upon Tyne and Bill Unruh at the University of British Columbia in Vancouver realised that an observer accelerated through the quantum vacuum should be bathed in electromagnetic radiation. The quantum vacuum becomes a real and detectable thing. This idea hit Haisch in February 1991, when Alfonso Rueda of California State University gave a talk about the Davies-Unruh effect at Lockheed Martin's Solar and Astrophysics Laboratory in Palo Alto. If an accelerated body sees radiation coming at it from the front, Haisch thought, that radiation might apply a retarding force. "I'm an astrophysicist," he says. "So I am used to the idea that radiation -- for instance, sunlight - can exert a pressure on bodies such as comet particles." Rueda said he would do some calculations. Some months later, he left a message on Haisch's answering machine in the middle of the night. When Haisch played it back the next morning he heard an excited Rueda saying, "I think I can derive Newton's second law." According to Rueda, photons boosted out of the quantum vacuum by an object's acceleration would bounce off electric charges in the object. The result is a retarding force which is proportional to the acceleration, as in Newton's second law, which defines inertial mass as the ratio of the force acting on an object to the acceleration produced. Haisch and Rueda, along with their colleague Harold Puthoff of the Institute for Advanced Studies in Austin, Texas, published their initial work in February 1994 (Physical Review A, vol 49, p 678). This electromagnetic drag certainly sounds like inertia. But do the calculations agree with the known inertial masses of subatomic particles? Why are quarks heavier than electrons, even though they have less charge? And why are the particles called muons and taus heavier than electrons, even though they appear to be identical in other ways? It might be because they are doing a different kind of dance. In deriving his result, Rueda adapted an old idea proposed by quantum pioneers Louis-Victor de Broglie and Erwin Schrsdinger. When low-energy photons bounce off electrons, they are scattered as if the electron were a ball of charge with a finite size. But in very high-energy interactions, the electrons behave more as if they are point-like. So de Broglie and Schrsdinger proposed that an electron is actually a point-like charge which jitters about randomly within a certain volume. This can account for both kinds of behaviour: at high energies, the interaction is fast and the electron appears frozen in place; at low energies, it is slow, and the electron has time to jiggle about so much that it appears to be a fuzzy sphere. Haisch and Rueda believe that de Broglie and Schrsdinger's idea was on the right lines. The electron's jitter could be caused by virtual photons in the quantum vacuum, just like the Brownian motion of a dust particle bombarded by molecules in the air. "Random battering by the jittery vacuum smears out the electron," says Haisch. This is important because Haisch and Rueda suspect that their inertia-producing mechanism occurs at a resonant frequency. Photons in the quantum vacuum with the same frequency as the jitter are much more likely to bounce off a particle, so they dominate its inertia. They speculate that muons and taus may be some kind of excited state of the electron, with a correspondingly higher resonance frequency. That would probably mean a greater mass, as there are more high-frequency vacuum photons to bounce off. Quarks might also be resonating in a different way from electrons. "If we knew what caused the resonance we would probably be able to explain the ratio of the various quarks' rest masses to the electron rest mass," says Haisch. The cause of such excitations might lie in string theory, which treats particles as tiny vibrating strings, but this is only conjecture. If inertial mass is an electromagnetic effect, why does the neutrino appear to have some mass, even though it doesn't feel electromagnetic forces? This might be easier to explain. The electromagnetic field is not the only field in the vacuum. There are two other force fields: the weak nuclear force and the strong nuclear force. Both could make contributions to mass in a similar way to the electromagnetic field. Neutrinos only feel the weak force, which could explain their small mass. Quarks feel the strong nuclear force, and that could affect their mass. It is even possible that strong-force fluctuations in the vacuum dominate the masses of quarks and gluons. As these contributions are much harder to work out than the electromagnetic ones, no one has attempted them yet. Vacuum-packed So much for inertia. But what about the force holding you to the floor? Can the vacuum account for gravitational mass too? The idea of linking gravity with the quantum vacuum was suggested by Russian physicist Andrei Sakharov in 1968 and has been developed recently by Puthoff. Haisch and Rueda's latest project is to connect this idea with their work on inertia. It's still highly speculative, but they think they can explain away gravity as an effect of electromagnetic forces. Oscillating charges in a chunk of matter affect the charged virtual particles in the vacuum. This polarised vacuum then exerts a force on the charges in another chunk of matter. In this rather tortuous manner the two chunks of matter attract each other. "This might explain why gravity is so weak," says Haisch. "One mass does not pull directly on another mass but only through the intermediary of the vacuum." Einstein's theory of general relativity already explains gravity beautifully in terms of the warping of space-time by matter, so this "geometrical" description ought to be compatible with the quantum-vacuum picture. Haisch points out that the curvature of space can only be inferred from the bending of the paths of light rays. But the polarised vacuum would bend light paths, just as a piece of glass does when light enters or leaves it. "The warpage of space might be equivalent to a variation in the refractive index of the vacuum," Haisch conjectures. "In this way, all the mathematics of general relativity could stay, intact, since space-time would look as if it were warped." And all the strange predictions of general relativity, such as black holes and gravitational waves, would be manifestations of this polarised vacuum. If they can get their idea to work, Haisch and Rueda will have a theory of quantum gravity -- the long-sought marriage of Einstein's general relativity with quantum mechanics. It would finally allow physicists to understand the first moments after the big bang, and the crushing singularity at the core of a black hole. That just leaves rest mass, the kind of mass that's equivalent to energy. According to Haisch, the Higgs might not be needed to explain rest mass at all. The inherent energy in a particle may be a result of its jittering motion, the buffeting caused by virtual particles in the vacuum. "A massless particle may pick up energy from it, hence acquiring what we think of as rest mass," he says. If this were the case, all three facets of mass would be different aspects of the battering of the quantum vacuum. "It would be a tidy package." It may be that there is no explanation for inertial and gravitational mass. They may just come hand in hand with rest mass. This is what many particle physicists believe. "Some people think Haisch and Rueda are on the right track, others think they are on a wild goose chase," says Paul Wesson, an astrophysicist at the University of Waterloo in Ontario, Canada. But if gravitational and inertial mass do emerge from the vacuum, perhaps we could take control of them. It might be possible to cancel mass, creating an inertia-less drive that could accelerate a spaceship to nearly the speed of light in the blink of an eye. To do this we would have to exclude quantum fluctuations from a region where there is matter -- blow a bubble in the vacuum. Haisch doesn't know if that is possible. "Nature does not abhor a vacuum," he says. "However, it may abhor a vacuum in the vacuum." This article appeared in the February 3 issue of New Scientist. Copyright 2001 - All rights reserved. From VM Mon Feb 19 10:22:11 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2523" "Monday" "19" "February" "2001" "01:02:43" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "51" "starship-design: Local Gas Density" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 2523 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1J6xFi14404 for starship-design-outgoing; Sun, 18 Feb 2001 22:59:15 -0800 (PST) Received: from mail1.mco.bellsouth.net (mail1.mco.bellsouth.net [205.152.111.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1J6xDQ14394 for ; Sun, 18 Feb 2001 22:59:13 -0800 (PST) Received: from nless (host-209-214-156-171.msy.bellsouth.net [209.214.156.171]) by mail1.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id BAA05821 for ; Mon, 19 Feb 2001 01:59:11 -0500 (EST) Message-ID: <001001c09a41$f7b8a980$f595fea9@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: starship-design: Local Gas Density Date: Mon, 19 Feb 2001 01:02:43 -0600 Looks like I missed my fuss! Anyway, it could have been a good one. I see some snippets quoted from posts I missed over the weekend that I lost my ISP, that I'll have to read in next quarter's archive. Like: >Did I miss something? I thought the local interstellar medium had been >determined to be thinner than once thought - like only 0.1 atom per cubic >meter... > >Lee Yup, recent supernova in the area cleaned out the area. The formal name is something lige a local bubble or something. Kelly Have you missed something? Priscella C. Frisch of the University of Chicago opined back in 1994 that we just entered an interstellar gas cloud. "Using cosmic-ray data and stellar spectra gathered by seven satellites... According to Frisch, until just a few thousand years ago, the solar system was cruising through interstellar space that was almost devoid of matter. Then, perhaps within historical times, 2,000-8,000 years ago, the solar system plunged into an interstellar gas cloud. This cloud is believed to be the remnant of the bubble of matter shot into space perhaps 250,000 years ago by a supernova in the Scorpius-Centaurus region." http://www.science-frontiers.com/sf098/sf098a04.htm (Frisch, Priscella C.; "Morphology and Ionization of the Interstellar Cloud Surrounding the Solar System," Science, 265:1423, 1994. Also: Peterson, I.; "Finding a Place for the Sun in a Cloud," Science News, 146:148, 1994.) More recently, Markus Landgraf et al. of ESA, working with the Ulysses probe which has been orbiting out of the ecliptic for 8 years, confirm the presence of a gas and dust cloud. 'The best match, they found, was with a mixture of silicates detected in interstellar clouds elsewhere in the Milky Way, suggesting that we are moving through an identical cloud. "We were very excited when we found that the composition fits," says Landgraf. The notion that we are travelling through an interstellar cloud is not new. First a cloud of gas was discovered moving through the solar system. Then by 1995, Ulysses had detected enough galactic dust grains to see that they travel through the solar system in the same direction as the gas, suggesting that the cloud consists of dust as well as gas.' http://www.spacedaily.com/news/stardust-99h.html Whether or not a "recent" supernova cleaned out the gas in our area, we stumbled into a cloud very recently. It's too soon to dismiss ram scoops; first let's get some hard info on what's really there. If we're in a cloud, rams will work. Johnny Thunderbird From VM Mon Feb 19 10:22:11 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["5194" "Monday" "19" "February" "2001" "04:47:17" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "80" "starship-design: Dirtside Fusion Energy" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 5194 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1JAjSM24618 for starship-design-outgoing; Mon, 19 Feb 2001 02:45:28 -0800 (PST) Received: from mail1.mco.bellsouth.net (mail1.mco.bellsouth.net [205.152.111.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1JAjQQ24610 for ; Mon, 19 Feb 2001 02:45:27 -0800 (PST) Received: from nless (host-216-78-116-218.msy.bellsouth.net [216.78.116.218]) by mail1.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id FAA00269 for ; Mon, 19 Feb 2001 05:45:23 -0500 (EST) Message-ID: <000901c09a61$90557a00$f595fea9@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: starship-design: Dirtside Fusion Energy Date: Mon, 19 Feb 2001 04:47:17 -0600 I was thinking on why I find fusion (in-system) drives so much easier to invent, than fusion power reactors. Fusion drives are simpler machines. Harnessing their power, for conversion to usable electricity, is a much harder problem. My approach to fusion is to use the technique which has demonstrated nuclear fusion in the laboratory since the 30's, hitting a target with a beam of fast ions. The principles I adopted were to use accelerators to produce fusion, and to avoid neutron production in the primary reaction, and to suppress secondary reactions. Since the beam is so fast, the target can be in any physical state, any temperature, or any degree of ionization. All that matters is what is in its nucleus, which is a sitting duck for the ion beam, so you will have fusion. By selecting the appropriate species for the ion beam and the target, you can keep neutrons from being produced, and you can have clean fusion, which is easier to live with. The proton-boron and proton-lithium reactions are clean. The reaction is linear in shape, with a gaseous target, which progressively absorbs the ion beam in fusion reactions down the beam. A tube of flowing hydrogen, terminated by a divergent region in a high transverse magnetic field, which divergent region is bounded by electrodes orthogonal to the field, forms a magnetohydrodynamics (MHD) generator. Thus if any events happen in that tube which produce ionization of the hydrogen, from energy being added to it, that energy will largely be recovered in the MHD generator region as direct current. If the tube carrying the hydrogen is surrounded by a boiler consisting of an annular vessel of water, any events that happen which add heat to the hydrogen, from energy added to it, that energy will largely be recovered as heat within the annular boiler. This energy can be recovered by flash evaporation of the superheated water against the blades of a turbine, which turns a generator. If you add energy to the hydrogen by means of a beam of lithium ions, much of the energy it took to accelerate the ions of lithium can be recovered from either the MHD generator, or the steam power plant. Power plants which use recondensing, triple expansion steam turbines achieve typical Carnot heat efficiencies approaching 30%. The single large-scale MHD power plant I know of, in Russia, operates at about 40% thermal efficiency. (Your car is perhaps 15% efficient.) So about a third of the energy introduced by the beam of lithium nuclei can be recycled. Except the lithium produces nuclear fusion in the hydrogen, which requires the calculation to be modified. The Earthbound fusion power reactor is thus characterized by a long, linear shape to absorb its power. The hydrogen effluent from the pipe, still no doubt too hot for turbines, has its energy scavenged magnetohydrodynamically, by flowing through a transverse magnetic field which diverts its charged components to electrode plates. It is then condensed in a liquifaction plant, fractionally distilled off the helium which is the sole fusion product, and recycled. Heat absorbed along the length of the pipe is removed by supercritical water, which is flash evaporated into steam to turn its own turbine. The electrical output from the generator is combined with the MHD power. Fusion does not require extremely fast collisions, nor exotic accelerators. Since simple electrostatic potential difference will boost ions to the speed needed to produce fusion, and since such potential difference can be generated with near perfect efficiency, accelerator design to generate nuclear fusion can be optimized. The Cockcroft-Walton rectifier stack is a device which generates high voltage electronically with high efficiency, already. Accelerators are presumed to be very lossy machines, but they don't have to be. As electrical devices, they are subject to rules which are very well understood. Since they do not involve thermal processes which have inherent loss, there is opportunity for optimization at every point of energy dissipation, so their engineering can work toward achieving efficiency levels above 99%. No process using heat can meet any such goal. Electrical motors and generators of large scale routinely exceed 95% efficiency in continuous operation. These figures include copper losses, iron losses and friction losses, none of which need be involved in accelerator operation. We know how to work with electrical machines in intimate detail, so the prospect of an extremely efficient accelerator is quite feasible. Fusion power in a pipe may be easier to handle. If the fusion reaction is extended linearly, the heat intensity at any point decreases. A long, skinny fusion reaction may be attenuated in heat intensity, to the point at which it can be held in a pipe. For a given ion beam intensity, the amount of heat any given section of the pipe must absorb, can be controlled by changing the flow speed of the target gas. Higher speed has the effect of lengthening the reaction zone, thus cooling the pipe. If this post isn't considered to be strictly on topic, consider it a test rig for a space drive, or actually a starship power plant. Johnny Thunderbird From VM Mon Feb 19 12:49:35 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2396" "Monday" "19" "February" "2001" "14:48:06" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "39" "starship-design: Mercury Polar Laser Station" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 2396 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1JKipX26109 for starship-design-outgoing; Mon, 19 Feb 2001 12:44:51 -0800 (PST) Received: from mail1.mco.bellsouth.net (mail1.mco.bellsouth.net [205.152.111.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1JKioQ26100 for ; Mon, 19 Feb 2001 12:44:50 -0800 (PST) Received: from nless (host-209-214-157-197.msy.bellsouth.net [209.214.157.197]) by mail1.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id PAA25497 for ; Mon, 19 Feb 2001 15:44:44 -0500 (EST) Message-ID: <000d01c09ab5$4d1bcec0$f595fea9@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: starship-design: Mercury Polar Laser Station Date: Mon, 19 Feb 2001 14:48:06 -0600 I don't believe in starships getting help from home, in the deceleration phase. There's no inherent reason that optics couldn't focus well enough to provide some energy help. Just call it a religious or political preference, or whatever. I just don't think starship passengers ought to rely on remote conditions, light years away, for their very survival. "Real sorry about that laser beam, folks. You know how it is, the political and economic situation just got completely impossible back here. You're lucky you're not around to see it, heh heh. Well, whenever you do go by Alpha Centauri, wave real fast for all of us, because you're headed into the wild black yonder. All of us here, really hope you'll understand..." But I do believe that a starship can use all the help it can get in the boost phase, as a supplement to its onboard energy capability. I'm not a fan of lightsails, because they lack legs. I don't think getting there is half the fun. Space for me, is all that stuff that's in the way, of where I want to be. So the way I would handle a laser beam, is to convert its energy to add to the Newtonian reaction boost. This note is just about siting. It seems clear that a polar station on the surface of the planet Mercury would be the ideal place to locate a deepspace laser. (It is not true that Mercury has an East Pole and a West Pole! It happens to have two equatorial hot spots, which get more zenith sunshine than elsewhere, because of its weird rotational resonance. That's all it is.) Arbitrarily selecting the North Pole, you have the important feature that black sky is always available anti-sunward for heat rejection. Trying to reject heat from a sunlit surface on Mercury is a frustration. Without a patch of cold black sky always in sight, you couldn't stay long. Needless to say, the other advantage of the location is constant steady sunlight. Strong sunlight. Ideal for converting it into beamed laser energy. There are some weak possible quibbles. A starship on a vector close to the ecliptic plane would get periodic outages in service, as Mercury went behind the Sun. Most destinations aren't on the ecliptic, and so the ship en route would be constantly illuminated by the laser. It might be suggested, just to orbit a laser station in free space. But Mercury has the advantage of local construction materials; the place is 70% iron! Johnny Thunderbird From VM Tue Feb 20 10:16:38 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["7116" "Tuesday" "20" "February" "2001" "01:56:55" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "109" "starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 7116 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1K7u1d26965 for starship-design-outgoing; Mon, 19 Feb 2001 23:56:01 -0800 (PST) Received: from mail1.mco.bellsouth.net (mail1.mco.bellsouth.net [205.152.111.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1K7u0Q26956 for ; Mon, 19 Feb 2001 23:56:00 -0800 (PST) Received: from nless (host-216-78-116-168.msy.bellsouth.net [216.78.116.168]) by mail1.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id CAA27908 for ; Tue, 20 Feb 2001 02:55:56 -0500 (EST) Message-ID: <006101c09b13$0e089020$f595fea9@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: starship-design: LINAC efficiency Date: Tue, 20 Feb 2001 01:56:55 -0600 Well, I shoulda known. The optimal stationing of laser power stations on Mercury has solar collection stations at the Not East Pole and the Not West Pole too. Shucks, I was hoping to get out of working at those hellacious places. Before you even get there, you have to have cooling tubes laid halfway around the planet, exactly, to meet you there. Such a project obviously involves construction in phases; you have first the (true) polar stations, which can see dark sky in the nadir direction, so they're coolable places. The second phase is building a quadrant tube around 1/4 of the planet from each pole, on brightside, to each hotspot, total of four planetary quadrant tubes, plus one between the hot spots for safety redundancy. As you build tubes in, you must spread out heatpipes (from the rotational poles) for veins in a leaflike growth of carbon plates, to glow dark red in the dark black and cool your living environment when they're in the dark, but with heat conduction shut down when they're sunlit. When your tubes all meet, you establish two planetary isotherms, which are the heat rejection channels for the energy system and life environment, with avoidance of coupling. These planetary heat pipes are single fault tolerant, for catastrophe at no one place can cause systems failure, and are the only way to keep your cool on Mercury's hot side. That's the only way you can build those fancy liquid lead boilers and stuff at the Not Hot Poles. Sure we can ship heat to the Cool Poles, and we do, in the Industrial Heat Tubes, but mainly we ship power, because in lossless helical mode waveguide tubes, it's a lot more portable than heat. Most of that power feeds the big starship pushers at the Cool Poles, large free-electron lasers. The planet's mostly iron, but nobody bothers to say "One lump or two?" any more. The mines are big borings at the poles, all the way through the crust to the planet's core. They have big mountains of slag all around their pits, with tracks tunneled through them for mass launchers to throw slugs of iron into a point in Lunar orbit. Mercury iron is usually uncompetitive with asteroid stainless, so it keeps piling up in those silver sparks, but Mercury has surplus energy, and keeps high hopes for a project someday that'll need lots of iron, and keeps building those big ring batteries for starships and asteroid pushers. The 1 g acceleration parameter isn't a "why" question, it's a "how" question. "Any way you have to" is the "how" answer. The "why" is because it's the only we can get there feeling comfortable with ourselves, which is not only the way we'd rather feel, but pretty darn close to a requirement for our health, and a starship with a sick crew is a bad sign rather than an economic savings. We don't go there. The people in that can are the most expensive people we got, and they have good credit with us. If we can, and if it's a matter of cost, we will send them to that planetary system of a remote star and bring them back in good health and relative comfort, just to prove we're a civilized species who will flagrantly expend resources for the few lucky enough to do our learning for us, so they will come back to us in good health and report at the best possible speed, what wonders they have seen. You must face the prospect that decades will lapse in many cases, to eventuate to centuries, between times Earth sees members of a ship's crew, even though spacers see seven years between journeys every time. These people have really, really, really good credit. Let me give a figure: one hundred atoms per cubic centimeter. There, now the estimates for space gas density quoted in this newsgroup this week span eight orders of magnitude! (Or so.) No, that's just the figure I have seen for typical cloud density. (An opposing view, from instruments on the same Ulysses, I found after my post on gas density: Gary P. Zank of the Bartol Research Institute at the University of Delaware -- who doesn't think we're in a cloud right now, thinks it might make us dead. "Currently, Zank says, the solar system is in a region of space containing between 3 and 4 particles per cubic inch.") http://www.sciencedaily.com/releases/1998/06/980602080449.htm but note that Landgraf published December 17, 1999 in Science, after Zank, and thinks we're in a cloud, and has seen the characteristic silicate dusts known to accompany gas clouds of 100 atoms/cc. That's a ramscoop of a different color. Local to us means everywhere we're likely to go soon, and the evidence suggests to me this space is permeated by such a relatively high density of gas. I'll not hesitate to declare the ramscoop revived, since within a year or two the Voyagers will be crossing theough the 100 AU heliopause, where the solar wind shocks against the interstellar wind, and we ought to be able to find out for sure, how soupy it is in our neighborhood. What I think would be a good magnet ring, would be a double annular aluminized polymer torus. Inside the inside ring would be a weblike pattern printed with thick-layer cuprate superconductor. A thin continuous stream of liquid helium flows over part of this pattern, the vapor pressure from which keeps the inner ring inflated. The outer ring enveloping it is held in place just because it's there, and because tiny columns of silica aerogel at intervals provide spacers separating it from its contained torus. The outer torus isn't inflated with anything if we can help it, for it provides the outer wall of the Dewar vessel to keep stray heat away from the inner tube inside it, and pushes on it to make it go forward. So the magnet ring is as light as we can get away with. After all, the things do wear out in a few months as their helium goes away, if nothing else happens to them first, like a vagrant dust speck that just wouldn't be repelled, and they have to be replaced. So we grow them from the front of the ship, and graduate them forward as they get larger, extruded from the little growbots around their rim, which we feed with neutral beams from the ship. Growbots spin with their rings, or they couldn't extrude right, and in fact we use them to help spin their rings. Just for sport, we shoot bullets out of the bow of our spaceship, and then push on the bullets with lasers, until those poor bullets are all worn out with erosion. Nobody really expects rocks to pop up out of empty space, but just in case anything ever did materialize, we would want it to have the bad luck to be met by an almost relativistic bullet, and not us. A flash in front would be bad news, because it would be real bright, in rays that aren't good for our health. It might crisp some leading rings, but that would be a better grade of bad news than if it got closer to flash. We don't even allow solids to get anywhere close to our bows. But since that never happens, this is just a useless precaution, except that any energy we beam forward ionizes the medium, and we use our ionic winds to stir up the atomic winds, which bring us our clear sailing. Johnny Thunderbird http://members.100free.com/users/jthunderbird From VM Tue Feb 20 10:16:38 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1578" "Tuesday" "20" "February" "2001" "00:43:07" "-0800" "Steve VanDevender" "stevev@efn.org" nil "30" "starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1578 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1K8hZX07345 for starship-design-outgoing; Tue, 20 Feb 2001 00:43:35 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1K8hXQ07340 for ; Tue, 20 Feb 2001 00:43:34 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f1K8hRl20362 for ; Tue, 20 Feb 2001 00:43:27 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f1K8hLb11682; Tue, 20 Feb 2001 00:43:21 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <14994.11803.291022.428950@localhost.efn.org> In-Reply-To: <006101c09b13$0e089020$f595fea9@nless> References: <006101c09b13$0e089020$f595fea9@nless> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: starship-design: LINAC efficiency Date: Tue, 20 Feb 2001 00:43:07 -0800 Johnny Thunderbird writes: > . . . You can woolgather and ramble on about ramscoops all you want, but if you don't actually run the numbers, it doesn't matter what your verbal arguments are. For example, can you really ionize enough of the interstellar gas around you to collect it with a ramscoop? Is the energy you spend ionizing the gas really going to be recouped when you put the gas through the fusion reactor? How do you get get around the problem of the ramscoop's drag as the ship's velocity through the interstellar medium increases? Is there really proof for any figure you want to quote (or just make up) for the density of interstellar gas, what does a properly-substantiated figure mean for the effectiveness of any hypothetical ramscoop, and what's the contingency plan if the ship runs through a local void? Or, when you claim that we _have_ to sustain 1g acceleration of the ship by thrust, have you really run the numbers to determine what the energy cost to do that is for a journey of a given distance? Once you've figured out the energy cost, how do you intend to obtain the energy needed to run the ship through a trip of a few tens of light-years? Note that the energy cost in that case is many times the mass of the payload, and that it's very untenable that any ramscoop could actually provide usable thrust, let alone 1g thrust, at very high relativistic speeds. Ultimately, engineering arguments aren't verbal; they're numerical. Given some very real and frequently forbidding physical constraints, can you actually make the numbers come out? From VM Tue Feb 20 17:54:29 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1263" "Tuesday" "20" "February" "2001" "20:43:57" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "46" "Re: starship-design: Local Gas Density" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1263 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1L1iBZ16257 for starship-design-outgoing; Tue, 20 Feb 2001 17:44:11 -0800 (PST) Received: from imo-r04.mx.aol.com (imo-r04.mx.aol.com [152.163.225.4]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1L1iAR16247 for ; Tue, 20 Feb 2001 17:44:10 -0800 (PST) Received: from KellySt@aol.com by imo-r04.mx.aol.com (mail_out_v29.5.) id z.3e.7b5dc30 (8231) for ; Tue, 20 Feb 2001 20:43:58 -0500 (EST) Message-ID: <3e.7b5dc30.27c4775d@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: Local Gas Density Date: Tue, 20 Feb 2001 20:43:57 EST In a message dated 2/19/01 1:04:02 AM, bugzappr@bellsouth.net writes: >More recently, Markus Landgraf et al. of ESA, working with the Ulysses >probe > >which has been orbiting out of the ecliptic for 8 years, confirm the > >presence of a gas and dust cloud. 'The best match, they found, was with >a > >mixture of silicates detected in interstellar clouds elsewhere in the Milky > >Way, suggesting that we are moving through an identical cloud. "We were >very > >excited when we found that the composition fits," says Landgraf. The notion > >that we are travelling through an interstellar cloud is not new. First >a > >cloud of gas was discovered moving through the solar system. Then by 1995, > >Ulysses had detected enough galactic dust grains to see that they travel > >through the solar system in the same direction as the gas, suggesting that > >the cloud consists of dust as well as gas.' > >http://www.spacedaily.com/news/stardust-99h.html > > > >Whether or not a "recent" supernova cleaned out the gas in our area, we > >stumbled into a cloud very recently. It's too soon to dismiss ram scoops; > >first let's get some hard info on what's really there. If we're in a cloud, > >rams will work. > > > >Johnny Thunderbird In a cloud of dust and silicates? From VM Wed Feb 21 10:05:14 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1116" "Wednesday" "21" "February" "2001" "06:41:20" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "21" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1116 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1LCbhh16263 for starship-design-outgoing; Wed, 21 Feb 2001 04:37:43 -0800 (PST) Received: from mail1.mco.bellsouth.net (mail1.mco.bellsouth.net [205.152.111.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1LCbgR16257 for ; Wed, 21 Feb 2001 04:37:42 -0800 (PST) Received: from nless (adsl-21-216-18.msy.bellsouth.net [66.21.216.18]) by mail1.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id HAA09350 for ; Wed, 21 Feb 2001 07:37:40 -0500 (EST) Message-ID: <002901c09c03$9a3874c0$0a0a0a0a@nless> References: <006101c09b13$0e089020$f595fea9@nless> <14994.11803.291022.428950@localhost.efn.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: LINAC efficiency Date: Wed, 21 Feb 2001 06:41:20 -0600 All right, Steve, I'll get to work on the numbers for a 1 g scenario, but I don't feel limited to using those technologies (ramscoops and fusion) you've indicated you don't like. Anything that works is fair. I already agreed ramscoop drag, as you pointed out, is a major factor restricting its use, particularly approaching relativistic velocity. I did mention this drag factor is a positive contribution during deceleration phase. Like a fusion generator, I think I can show that a ram scoop is better to have, than to lack. As I pointed out in my last post, none of us know the local interstellar gas density. To recognize that, is better than to think we know it, when we don't. I shared all the most recent publications I noticed, which favor a higher density figure, than the ones which have been taken as rendering ramscoops unfeasible. Kelly, the silicate dust excited Dr. Landgraf, specifically because it marks gas clouds elsewhere. Seeing it here, probably means we're in a gas cloud, just like the others seen previously. Being in a gas cloud means ram scoops deserve a closer look. Johnny Thunderbird From VM Wed Feb 21 14:54:54 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["463" "Wednesday" "21" "February" "2001" "17:38:30" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "20" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 463 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1LMd3020587 for starship-design-outgoing; Wed, 21 Feb 2001 14:39:03 -0800 (PST) Received: from imo-r14.mx.aol.com (imo-r14.mx.aol.com [152.163.225.68]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1LMd1R20580 for ; Wed, 21 Feb 2001 14:39:01 -0800 (PST) Received: from KellySt@aol.com by imo-r14.mx.aol.com (mail_out_v29.5.) id z.c8.11124c62 (4399) for ; Wed, 21 Feb 2001 17:38:46 -0500 (EST) Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: LINAC efficiency Date: Wed, 21 Feb 2001 17:38:30 EST In a message dated 2/21/01 6:39:44 AM, bugzappr@bellsouth.net writes: > > >Kelly, the silicate dust excited Dr. Landgraf, specifically because it >marks > >gas clouds elsewhere. Seeing it here, probably means we're in a gas cloud, > >just like the others seen previously. Being in a gas cloud means ram scoops > >deserve a closer look. > > If we were in a dust clooud, it wouldn't it show up in images? Regardless of that, you still have the weight problem. From VM Thu Feb 22 10:50:47 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2664" "Wednesday" "21" "February" "2001" "21:12:25" "-0800" "Steve VanDevender" "stevev@efn.org" nil "46" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 2664 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1M5D2r23307 for starship-design-outgoing; Wed, 21 Feb 2001 21:13:02 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1M5CxR23298 for ; Wed, 21 Feb 2001 21:12:59 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f1M5Cso08494 for ; Wed, 21 Feb 2001 21:12:54 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f1M5Cfm19095; Wed, 21 Feb 2001 21:12:41 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <14996.40889.670276.697844@localhost.efn.org> In-Reply-To: <002901c09c03$9a3874c0$0a0a0a0a@nless> References: <006101c09b13$0e089020$f595fea9@nless> <14994.11803.291022.428950@localhost.efn.org> <002901c09c03$9a3874c0$0a0a0a0a@nless> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: LINAC efficiency Date: Wed, 21 Feb 2001 21:12:25 -0800 bugzapper writes: > All right, Steve, I'll get to work on the numbers for a 1 g scenario, but I > don't feel limited to using those technologies (ramscoops and fusion) you've > indicated you don't like. Anything that works is fair. I already agreed > ramscoop drag, as you pointed out, is a major factor restricting its use, > particularly approaching relativistic velocity. I did mention this drag > factor is a positive contribution during deceleration phase. Like a fusion > generator, I think I can show that a ram scoop is better to have, than to > lack. My point is not so much that ramscoops are bad as that ramscoops probably cannot do the things you want them to do, in particular sustain 1 g acceleration to high relativistic speeds. And I agree that using a ramscoop field to brake may actually be very useful, particularly if combined with an external source of thrust in the origin system to help boost the ship up to speed. > As I pointed out in my last post, none of us know the local interstellar gas > density. To recognize that, is better than to think we know it, when we > don't. I shared all the most recent publications I noticed, which favor a > higher density figure, than the ones which have been taken as rendering > ramscoops unfeasible. My guess is that the higher density estimates you're citing are probably too optimistic. Unfortunately my copy of _Astrophysical Formulae_ doesn't clearly indicate the observational bounds on the density of interstellar hydrogen (although it has lots of nice complicated formulae on how to compute column density of interstellar gas from observed emission and absorption spectra). If I get a chance I'll see if I can chase down some of the references it has to other publications that might have more definite statements. Whatever the local interstellar medium density is, it can be confirmed by observational measurements. > Kelly, the silicate dust excited Dr. Landgraf, specifically because it marks > gas clouds elsewhere. Seeing it here, probably means we're in a gas cloud, > just like the others seen previously. Being in a gas cloud means ram scoops > deserve a closer look. Given the other limits of ramscoops, being in a higher-density region of the galaxy probably would only mean we can get the ship up to the fairly low velocity limit of the ramscoop sooner. Interestingly, in some of the more credible hard science fiction novels I've read that have slower-than-light universes, the authors have had ramscoop ships that reach about .3 to .4 c at their limits of effectiveness. I'd be curious what research they did to choose that range of limit velocities. From VM Thu Feb 22 10:50:47 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1291" "Thursday" "22" "February" "2001" "04:02:25" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "23" "Re: starship-design: LINAC efficiency" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1291 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1M9x3Y24089 for starship-design-outgoing; Thu, 22 Feb 2001 01:59:03 -0800 (PST) Received: from mail1.mco.bellsouth.net (mail1.mco.bellsouth.net [205.152.111.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1M9x1R24082 for ; Thu, 22 Feb 2001 01:59:01 -0800 (PST) Received: from nless (adsl-21-217-53.msy.bellsouth.net [66.21.217.53]) by mail1.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id EAA09484 for ; Thu, 22 Feb 2001 04:59:00 -0500 (EST) Message-ID: <000d01c09cb6$91c101a0$0a0a0a0a@nless> References: <006101c09b13$0e089020$f595fea9@nless> <14994.11803.291022.428950@localhost.efn.org> <002901c09c03$9a3874c0$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: LINAC efficiency Date: Thu, 22 Feb 2001 04:02:25 -0600 Working on it, Steve. Learning all I never wanted to know about plasma dynamics. Thinking about pushing a cone spiral of eroding (maybe sodium) bullets, with lasers, ahead of the ship, ahead of rings and all. Would love to induce vorticity in the medium, by this ionization on the boundaries of bullet wake shockwaves. With sodium vapor curtains in front of you, the coup de grace excitation to give ionization might come in the radio frequencies. Shock ionization in the wake of a near-relativistic bullet. Those bullets are part of our ship's eyes, also. We're kind of near-sighted in front, the way that's dazzling bright blue. If there's anything waiting for us forward, the bullet shock wave in the interstellar medium will glow when it hits that speck, so we can shoot charge on the speck to repel it. If it's bigger, we can divert a trailing bullet to meet it, and push on that bullet hard. Bullet shock waves provide ionization, as I said, to help the magnets push the wind our way. The inflated magnet rings are pushed on with beams, so we can control their charge. Making them mutually repulsive helps keep them balanced in their conical stack. Making them positive gains us electrons, which the growbots fire back to us in beams. Musings while I'm reading. Johnny Thunderbird From VM Thu Feb 22 15:32:48 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["4971" "Thursday" "22" "February" "2001" "16:38:52" "-0600" "L. Parker" "lparker@cacaphony.net" nil "82" "starship-design: Changing Orbit Is Simple, Really" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 4971 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1MMjAG29406 for starship-design-outgoing; Thu, 22 Feb 2001 14:45:10 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1MMj4R29014 for ; Thu, 22 Feb 2001 14:45:08 -0800 (PST) Received: from broadsword (p465.gnt.com [204.49.91.81]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id QAA31855 for ; Thu, 22 Feb 2001 16:45:08 -0600 Message-ID: <000401c09d20$f0038250$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MIMEOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "Starship-Design \(E-mail\)" Subject: starship-design: Changing Orbit Is Simple, Really Date: Thu, 22 Feb 2001 16:38:52 -0600 Changing Orbit Is Simple, Really By Billy Cox Florida Today posted: 02:16 pm ET 21 February 2001 The distance from Earth to the Sun -- roughly 93 million miles -- is known as an astronomical unit (AU). So when somebody says Jupiter is five AUs out, that adds up to, well, whatever. And if somebody says something is 30,000 AUs away, you feel like the straight man in Revenge of the Nerds IV, so you zone out and switch channels. But somewhere out there, at around 30,000 AUs, along the outer band of a massive cosmic debris field called the Oort Cloud, something very big and very weird is going on. Because it hasn't been recorded visually, it only can be inferred, like black holes. Whatever it is, the thing appears to be warping the orbital patterns of comets. Scientists on opposite sides of the Atlantic Ocean who've measured the sucker's effects are calling it The Perturber. The Perturber isn't necessarily headed this way, nor does its crypto-life pass for breaking news anymore; reports were published in the Monthly Notices of the Royal Astronomical Society, as well as the journal Icarus, in late 1999. What gives us pause is an ostensibly unrelated paper accepted last week by Astrophysics and Space Science. More on that in a moment. First, since nobody actually has seen The Perturber, it has a large audience of skeptics. On the other hand, since two teams of scientists -- one from Louisiana University-Lafayette, another at Open University in England -- came to similar conclusions using contrasting methods, The Perturber probably is worth a sharper lens. According to Louisiana U. physics professor Dr. Dan Whitmire, a team of UCLA researchers sent a proposal to NASA for fingerprinting The Perturber in the infrared spectrum, but it didn't fly. So, until new instrumentation comes along, the itinerant enigma will remain a source of speculation. Whitmire says nothing about The Perturber has changed since the peer-review papers came out in '99, other than the observation of even more comet patterns bending along puzzling gravity contrails. The guesswork continues, naturally, and the bulk of it holds that something with this much clout's gotta be huge -- something like three times the size of Jupiter, at least. Maybe it's our Sun's long-lost twin companion, the last gasp of an imploding brown dwarf. That's what Whitmire thinks. But in England, scientist John Murray thinks it's a planet that got ejected from a different solar system. Key word: ejected. Which brings us to the journal of Astrophysics and Space Science. By now, it should be pretty obvious we're in a global warming headlock. Climatologists are warning us this year's freakish blizzards in the northern latitudes are the result of the rush of freshwater from the disintegrating polar caps altering ocean currents and jet stream patterns on a broad scale. Locally, we're experiencing desert conditions on the drought index again: Last Saturday's choking fire haze was 1998 all over again. So, we've gotta do something. Scientists at the University of California-Santa Cruz have an idea: Let's move Earth farther away from the Sun. We're gonna have to do it anyway, because solar gases will begin expanding in 1.1 billion years as the Sun's inevitable unraveling unfolds. Maybe we should go ahead and do it now, so we can cool off earlier. It's really little more than an engineering project, insists planetary scientist Don Korycansky. All you do is take a 62-mile- (100-kilometer-) wide asteroid (you can find these boys outside Pluto in the Kuiper Belt), and give it a nudge toward Jupiter by sticking a fusion rocket on the thing. The goosed asteroid then would slingshot around the Sun and swing past Earth on its return to Jupiter. Each roundtrip would take 6,000 years, but the passes would generate gravity assists that theoretically would push us to a more moderate 140 million miles (225 million kilometers) from the Sun. There are problems. The report says we could lose the Moon. Or Earth's spin axis could accelerate, meaning days and nights might last for just a few hours each. Oh yeah, and Jupiter might get sucked 10 million miles (16 million kilometers) closer to the Sun, and we might get pelted by an endless rain from the Asteroid Belt. And, oh yeah, Venus and Mars must stay in their orbits for the plan to work. And there's a possibility the 62-mile-wide asteroid could veer into Earth and, write the scientists, "sterilize the biosphere most effectively, at least to the level of bacteria." And they don't say this next part, but it stands to reason: Maybe the residents of The Perturber already tried that, and The Perturbians accidentally ejected themselves into the Oort Cloud. Well, you never know. It's like National Missile Defense. We need to spend the money and find out. Given what's at stake, a few hundred billion dollars is nothing. Billy Cox can be reached at (321) 242-3774, or Florida Today, P.O. Box 419000, Melbourne, FL 32941-9000. From VM Mon Feb 26 10:24:50 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["3202" "Saturday" "24" "February" "2001" "02:46:17" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "53" "starship-design: Hydrogen Recombination Jet" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 3202 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1O8gZ711611 for starship-design-outgoing; Sat, 24 Feb 2001 00:42:35 -0800 (PST) Received: from mail1.mco.bellsouth.net (mail1.mco.bellsouth.net [205.152.111.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1O8gYR11606 for ; Sat, 24 Feb 2001 00:42:34 -0800 (PST) Received: from nless (adsl-20-122-172.msy.bellsouth.net [66.20.122.172]) by mail1.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id DAA29782 for ; Sat, 24 Feb 2001 03:42:33 -0500 (EST) Message-ID: <000901c09e3e$436aaf40$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MIMEOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: starship-design: Hydrogen Recombination Jet Date: Sat, 24 Feb 2001 02:46:17 -0600 The Free Lunch - Interstellar External Combustion Turbojet What if there were a chemical reaction which would be self-propagating, remotely controllable, spectacularly energetic, and self-damping when we remove our structural mechanism; which could provide thrust without requiring a huge energy input on our part? What space is full of, is a low density of monatomic hydrogen neutral gas. The most urgent thing atomic hydrogen wants to do, is to recombine chemically with another atom just like it, to form molecular (diatomic) hydrogen. It wants to do that bad enough, to make it the most energetic chemical reaction possible. Simple compression, while keeping it cool enough to stay tolerable by hydrogen molecules, will ignite this reaction. I think the starship is about to become conceptually simpler. There is free energy to be gathered in space. Though everyone sneers at using chemical propulsion in starships, for this one you don't have to carry fuel, which is a big plus. That it's the strongest chemical reaction also helps. It will provide thrust for your ship, if you shape it right; even a 1 g thrust, if you burn enough of it. Making the starship driven by an external combustion engine, poetically a flaming whirlwind, technically an external combustion scramjet, which is a "supersonic combustion ramjet" of the atmosphere, but this is a spaceship. There is not really "combustion" in this jet, for there is neither oxidation nor reduction chemically, but it can get hot and noisy as you make it. Burning is a fair shorthand name for an atomic hydrogen torch, hot enough to conquer any material. The way I see to use this is with a twist, which must be compensated by a complementary moment of torque thrust, to the extent its torsion affects the stability of the starship's orientation. The decision to use an artificially created vortex of interstellar gas was motivated by the argument, that ultrascale machinery cannot be built with solids, because it costs too much. A ramscoop can collect from a large frontal area cheaply, using a cyclonic storm started far ahead. So if you know how to start a whirlwind, using explosive fuel (recombining atomic hydrogen) to produce torque, you can later apply pinch on the waist of that tornado, to ignite general recombination of all the remaining atomic hydrogen downwind in the vortex. You have constructed a large scale turbojet in the scanty winds of space. You can expend a great deal of energy on rays, bullets, beams and fields, supporting structures made of shock fronts, ion sheaths, acoustic standing waves, vapor curtains and similar ephemeral constructions, to make your ship's vicinity a geometric sculpture, without spending as much energy as if you had to twist that cyclone yourself. When you burn the interstellar gas for thrust, there's no need to be thrifty with it, so you can set the acceleration level to whatever is most comfortable for you. Like 1 g. This vortex engine is a one way design; I don't think there is any way to turn it around. Lucky there are other ways to slow down. Not bad for free, but I think I'll keep my tuned LINAC around, for when I really want legs on my starship. Johnny Thunderbird From VM Tue Feb 27 09:01:22 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["376" "Tuesday" "27" "February" "2001" "15:06:48" "-0000" "\"Andrew \\\"Daishi\\\" West\"" "andrew@hmm.u-net.com" nil "10" "starship-design: Space Group Plans Solar Sailing Voyage" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 376 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1RF5Ta10182 for starship-design-outgoing; Tue, 27 Feb 2001 07:05:29 -0800 (PST) Received: from mail1-gui.server.ntli.net (mail1-gui.server.ntli.net [194.168.222.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1RF5OR10156 for ; Tue, 27 Feb 2001 07:05:24 -0800 (PST) Received: from daishi ([62.252.49.166]) by mail1-gui.server.ntli.net (Post.Office MTA v3.1 release PO203a ID# 0-33929U70000L2S50) with SMTP id AAA16807 for ; Tue, 27 Feb 2001 14:58:28 +0000 Message-ID: <000801c0a0ce$e8558600$a631fc3e@daishi> References: <000901c09e3e$436aaf40$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MIMEOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "Andrew \"Daishi\" West" From: "Andrew \"Daishi\" West" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: starship-design: Space Group Plans Solar Sailing Voyage Date: Tue, 27 Feb 2001 15:06:48 -0000 Space Group Plans Solar Sailing Voyage Reuters Feb 26 2001 6:11PM WASHINGTON (Reuters) - In what sounds like a purely fantastic voyage, a private U.S. group that boosts planetary exploration said on Monday it plans to use the power of light to sail a giant windmill-shaped contraption through space. http://my.aol.com/news/news_story.psp?type=1&cat=0200&id=0102261811330216 From VM Tue Feb 27 09:01:22 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["9177" "Tuesday" "27" "February" "2001" "16:24:47" "+0100" "Zenon Kulpa" "zkulpa@ippt.gov.pl" nil "192" "Re: starship-design: Space Group Plans Solar Sailing Voyage" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 9177 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1RFRSq17955 for starship-design-outgoing; Tue, 27 Feb 2001 07:27:28 -0800 (PST) Received: from ippt.gov.pl (zmit1.ippt.gov.pl [148.81.53.8]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1RFRQR17946 for ; Tue, 27 Feb 2001 07:27:26 -0800 (PST) Received: (from zkulpa@localhost) by ippt.gov.pl (8.8.5/8.7.3-zmit) id QAA08534 for starship-design@lists.uoregon.edu; Tue, 27 Feb 2001 16:24:47 +0100 (MET) Message-Id: <200102271524.QAA08534@ippt.gov.pl> Precedence: bulk Reply-To: Zenon Kulpa From: Zenon Kulpa Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: Space Group Plans Solar Sailing Voyage Date: Tue, 27 Feb 2001 16:24:47 +0100 (MET) > From owner-starship-design@lists.uoregon.edu Tue Feb 27 16:20:55 2001 > From: "Andrew \"Daishi\" West" > > Space Group Plans Solar Sailing Voyage > Reuters > Feb 26 2001 6:11PM > > WASHINGTON (Reuters) - In what sounds like a purely fantastic voyage, a > private U.S. group that boosts planetary exploration said on Monday it plans > to use the power of light to sail a giant windmill-shaped contraption > through space. > > http://my.aol.com/news/news_story.psp?type=1&cat=0200&id=0102261811330216 > ----- Begin Included Message ----- >From bounce-planetarysociety-1715@lists.planetary.org Tue Feb 27 01:34:50 2001 Delivered-To: uran-uranos@uranos.eu.org Date: Mon, 26 Feb 2001 14:37:35 -0800 To: "planetarysociety" From: Charlene Anderson Subject: First Solar Sail Set to Launch Dear Members and Friends of The Planetary Society-- It has been nearly a year since we last sent out an e-mail update. But as you read on, I think you'll see it's not because we haven't been busy! We're back, and with the most exciting announcement in Planetary Society history. We are about to launch the first solar sail mission ever -- and the first space mission by a public-interest organization. Our goal is to test sail deployment during a sub-orbital flight in April, and to fly the Earth-orbital mission by the end of the year. The funding for our mission comes from Cosmos Studios, a science-based media and entertainment venture led by Ann Druyan, wife and collaborator of Society co-founder Carl Sagan. This is a bold venture -- the biggest, most ambitious project The Planetary Society has ever undertaken. We hope you will join us as we launch the first solar sail mission, and take the first step down a path that leads to the planets -- and perhaps, one day, to the stars. Louis Friedman Executive Director The text of the official press release follows. THE PLANETARY SOCIETY AND COSMOS STUDIOS ANNOUNCE COSMOS 1 THE FIRST SOLAR SAIL SPACE MISSION For News and Updates on this mission, visit http://planetary.org/ Pasadena, CA. - February 26, 2001: The Planetary Society's Cosmos 1: The First Solar Sail mission, sponsored by Cosmos Studios, is set to test in April with the prime mission scheduled to launch between October - December this year. The deployment test flight will launch from a Russian submarine in the Barents Sea and will be lifted into a thirty-minute sub-orbital flight from a Russian Volna rocket, a converted ICBM. The main mission, with the goal of first solar sail flight, will launch into Earth orbit later this year, also from a Volna rocket. Once in orbit, the solar sail spacecraft will be as bright as the full moon (although only a point in the sky) and will be visible from places on Earth with the naked eye. Images of the sail in flight will be sent to Earth from two different cameras on-board the spacecraft. The mission represents the first private mission of space exploration technology and the first mission by a private space interest organization. It will explore and develop technology that could open the door to future flights throughout the solar system and beyond. The mission will be carried out by a unique, privately funded Russian-American space venture. "This could be a pivotal moment for space exploration, said Louis Friedman, Executive Director of The Planetary Society and Project Director of Cosmos 1. "Solar Sailing is a grand adventure as well as an important leap in technological innovation." Space sailing is done not with wind, but with reflected light pressure - pushing on giant sails, changing the orbital energy and spacecraft velocity continuously. The sunlight pressure is powerful enough to push spacecraft between the planets from Mercury out to Jupiter. Beyond Jupiter, and out to the stars, space sailing can be done using powerful lasers focused over long distances in space. "The lasers themselves will be powered by solar energy - keeping the spirit of solar sailing alive to other stars," added Friedman. "The many special aspects of this first attempted solar sail flight - Russian-American collaboration; use of weapons of war for launching peaceful technologies for humankind's future; attempting a very low cost, privately funded space initiative in a one-year time schedule; realizing one of Carl Sagan's dreams; working with Ann Druyan, Sagan's wife and long-time collaborator, who, together with Joe Firmage, had the courage to fund this project - make us extremely proud of what we have accomplished before we've even launched," said Friedman. "We have lingered long enough on the shores of the cosmic ocean. We are ready at last to set sail for the stars," wrote Sagan and Druyan in their television series, Cosmos. "This is a Kitty Hawk moment to us. We feel as if we've been given the chance to outfit the Wright Brothers' Bicycle Shop," said Ann Druyan, CEO of Cosmos Studios, Inc. "We at Cosmos Studios are honored to work with the brilliant scientists and engineers of many countries brought together by The Planetary Society for one great purpose. We are proud to be part of this historic mission, which is a critical baby step to the stars. It's also emblematic of Cosmos Studios' philosophy: to support good science, clean high technology and bold exploration, and to engage the widest possible audience in the romance of the adventure." The low cost of this mission is made possible due to the Russians ability to "piggy-back" on a successful program in developing an inflatable re-entry vehicle. Once injected into Earth's orbit, the sail will be deployed by inflatable tubes, pulling out the sail material and then rigidizing the structure. The sail is constructed into eight "blades" or "petals" - roughly triangular in shape. They can be turned (pitched) like helicopter blades, and depending on how they are turned, the sunlight will reflect in different directions. This is how the attitude of the spacecraft is controlled and how the sail can "tack." Low cost is also made possible by use of the Volna rocket, manufactured by the Makeev Rocket Bureau in Russia. The Babakin Space Center is the prime contractor for the project - the company is a spin-off organization of NPO Lavochkin, the largest manufacturer of robotic spacecraft in the world. The April launch will be a sub-orbital flight test of the deployment of two solar sail blades. An inflatable re-entry shield is planned to bring the pictures of the deployment back to a landing and recovery site in Kamchatka. The actual solar sail flight will commence from an 850 km circular orbit, with a launch being planned in a window between October - December of this year. The sail will be 600 square meters of aluminized mylar, constructed into 8 blades. Solar sailing enables space travel without fuel. Applications from space weather satellites that can hold position against the force of gravity, to interplanetary shuttles carrying cargo between the planets and the asteroids and comets are all part of the solar sailing future. By diving in close to the Sun, future solar sails will achieve enormous velocities enabling rendezvous with any solar system object, or, as mentioned above, a flight to the stars. Cosmos 1 is staffed by a world team of Americans and Russians. The Planetary Society website has a dedicated section to this mission, which includes an animation of the mission, spacecraft details, updates and news releases. It will allow the world public to follow and participate in this mission. This site is open to the public and is located at http://planetary.org. This will be the first space mission that will utilize a website to continuously interface the sequence of the mission with the general public, allowing continued and uninterrupted public participation. Additional information will also be available at the Cosmos Studios website located at http://carlsagan.com. The Planetary Society is headquartered in Pasadena, California, U.S.A. The organization was co-founded by Carl Sagan, Bruce Murray and Louis Friedman in 1980 to advance the exploration of the solar system, and to continue the search for extraterrestrial life. With 100,000 members in over 140 countries, the Society is the largest space interest group in the world. Cosmos Studios creates science-based entertainment that seeks to thrill and engage the broadest possible audience through the convergence of television, cinema and the Internet. The company creates programming that makes news, entertains, uplifts and inspires humankind's quest for knowledge, our understanding of cosmic evolution, and our place in its great story. Cosmos Studios is based in Los Angeles, California and is managed from Ithaca, New York. # # # # # # # # # ******************** Charlene M. Anderson Associate Director The Planetary Society charlene.anderson@planetary.org http://planetary.org office: 626-793-5100 fax: 626-793-5528 ----- End Included Message ----- From VM Wed Feb 28 10:18:58 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2567" "Wednesday" "28" "February" "2001" "10:09:11" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "45" "starship-design: Ice Impact Terraforming" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 2567 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1SG93717842 for starship-design-outgoing; Wed, 28 Feb 2001 08:09:03 -0800 (PST) Received: from mail2.mco.bellsouth.net (mail2.mco.bellsouth.net [205.152.111.14]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1SG92J17835 for ; Wed, 28 Feb 2001 08:09:02 -0800 (PST) Received: from nless (adsl-21-217-254.msy.bellsouth.net [66.21.217.254]) by mail2.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id KAA09577 for ; Wed, 28 Feb 2001 10:59:34 -0500 (EST) Message-ID: <000f01c0a1a0$d106d8a0$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: starship-design: Ice Impact Terraforming Date: Wed, 28 Feb 2001 10:09:11 -0600 Terraforming by Impact A technique which must become standard in gaining new places to live, is smashing rocky planets, which orbit in the habitable thermal zone, with ice bodies from the outer system. Rock worlds which lack a thick atmosphere and liquid water, can suddenly gain both in this way. That a planet may be gravitationally unable to hold gases in the long term, does not necessarily disqualify it from being made livable on our time scales. The moon, for example, would only hold air pressure for 4000 years; so? Refreshing the pressure with another ice ball, every millenium or so, we could live with. In contrast to carefully reasoned schemes to restore the Martian atmosphere (from its rocks) over centuries, we will probably implement the plan which will do the job in twenty, noisy, minutes. By guaging the impact velocity of the ice ball, you can leave the planet with a new mountain of crushed ice, a new atmosphere of water vapor, and a brisk planetary wash job with a shallow flood, to scour away the salts on its surface. For cracking off water's excess hydrogen to let it escape, a high flux of ultraviolet is convenient in this job. From the start, the steam at the lowest level will be relatively enriched in oxygen, and depleted in hydrogen. This will allow high productivity (aerobic photosynthesizing) microbes to thrive immediately at the surface. This instant biosphere will be limited by carbon availability, not water nor air. To rush things, we might design the initial greenhouse effect, so the climate for the first few decades stays around the cozy 37 degrees Celsius, of the incubator. Don't know if this should be mentioned, but if a planet's surface really has a carbon shortage, there's lots of it around, in free space rocks. For nitrogen, though, you have to find it a long way out, where it stays really cold. Ammonia can be found (as an ice) anywhere uphill of Saturn. (It makes more sense to bring in reduced nitrogen, which plants can use immediately, than the element, which costs energy to fix.) I won't bring in any dynamic considerations of impact engineering, at this point, or somebody will ask me for numbers. The numbers, after all, are the whole project. I will mention an intuitive suspicion, that somewhere within the consideration of impacting bodies, lies a solution by which we could adjust the rotational parameter of large bodies, without catastrophe to their orbits. Mars doesn't need that treatment; it has a perfect length day for Earthly plants. Further deponent saith not. Johnny Thunderbird From VM Wed Feb 28 10:18:58 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1538" "Wednesday" "28" "February" "2001" "16:34:15" "-0000" "Walker, Chris" "Chris.Walker@BSKYB.COM" nil "37" "RE: starship-design: Ice Impact Terraforming" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1538 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1SGbKI02486 for starship-design-outgoing; Wed, 28 Feb 2001 08:37:20 -0800 (PST) Received: from ns0.sky.co.uk (mail.sky.co.uk [193.117.250.170]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1SGbIJ02473 for ; Wed, 28 Feb 2001 08:37:18 -0800 (PST) Received: from ost_exch_bhs02.bskyb.com (ost_exch_ldbal.sky.co.uk [195.153.219.158]) by ns0.sky.co.uk (8.9.1/8.9.1) with ESMTP id QAA02177 for ; Wed, 28 Feb 2001 16:19:30 GMT Received: from ost_exch_bhs02.bskyb.com (unverified) by ost_exch_bhs02.bskyb.com (Content Technologies SMTPRS 4.1.5) with ESMTP id for ; Wed, 28 Feb 2001 16:34:28 +0000 Received: by OST_EXCH_BHS02 with Internet Mail Service (5.5.2650.21) id ; Wed, 28 Feb 2001 16:31:10 -0000 Message-ID: MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2650.21) Content-Type: text/plain; charset="iso-8859-1" Precedence: bulk Reply-To: "Walker, Chris" From: "Walker, Chris" Sender: owner-starship-design@lists.uoregon.edu To: Starship Design List Subject: RE: starship-design: Ice Impact Terraforming Date: Wed, 28 Feb 2001 16:34:15 -0000 > -----Original Message----- > From: bugzapper [mailto:bugzappr@bellsouth.net] > Sent: 28 February 2001 16:09 > To: Starship Design List > Subject: starship-design: Ice Impact Terraforming > > The moon, for example, would only hold air pressure for 4000 years; so? > Refreshing the pressure with another ice ball, every millenium or so, we > could live with. I'm not entirely convinced that the people living on the moon, developed and colonised as it might be over a period of 1000 years, would "live with" the impact of a great big ball of ice on their wee world. How did that Dave Barry quote go? "What happens if a big asteroid hits the Earth? Judging from realistic simulations involving a sledge hammer and a common laboratory frog, we can assume it will be pretty bad." ;) Perhaps best keep this technique for terraforming large bodies that are going to hold their atmosphere. Alternatively, once you've pummelled the moon the first time, then use a gentler technique (insert speculative Sci-Fi method here) to maintain the atmosphere... Chris ********************************************************************** Information in this email is confidential and may be privileged. It is intended for the addressee only. If you have received it in error, please notify the sender immediately and delete it from your system. You should not otherwise copy it, retransmit it or use or disclose its contents to anyone. Thank you for your co-operation. ********************************************************************** From VM Wed Feb 28 13:48:24 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1860" "Wednesday" "28" "February" "2001" "15:22:22" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "43" "Re: starship-design: Ice Impact Terraforming" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 1860 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1SLMTQ06177 for starship-design-outgoing; Wed, 28 Feb 2001 13:22:29 -0800 (PST) Received: from mail2.mco.bellsouth.net (mail2.mco.bellsouth.net [205.152.111.14]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1SLMOJ06155 for ; Wed, 28 Feb 2001 13:22:27 -0800 (PST) Received: from nless (adsl-21-218-80.msy.bellsouth.net [66.21.218.80]) by mail2.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id QAA21733 for ; Wed, 28 Feb 2001 16:13:01 -0500 (EST) Message-ID: <000501c0a1cc$8f139740$0a0a0a0a@nless> References: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Ice Impact Terraforming Date: Wed, 28 Feb 2001 15:22:22 -0600 > > The moon, for example, would only hold air pressure for 4000 years; so? > > Refreshing the pressure with another ice ball, every millenium or so, we > > could live with. >From Chris Walker: > I'm not entirely convinced that the people living on the moon, developed and > colonised as it might be over a period of 1000 years, would "live with" the > impact of a great big ball of ice on their wee world. How did that Dave > Barry quote go? > > "What happens if a big asteroid hits the Earth? Judging from realistic > simulations involving a sledge hammer and a common laboratory frog, we can > assume it will be pretty bad." > > ;) > > Perhaps best keep this technique for terraforming large bodies that are > going to hold their atmosphere. Alternatively, once you've pummelled the > moon the first time, then use a gentler technique (insert speculative Sci-Fi > method here) to maintain the atmosphere... > > Chris ------------ Yeah, I kind of figured that. If someone can move big ices in, they can be parked in orbit and sliced into smaller pieces. Small and slow enough, and ice cubes could be dribbled in without touching the surface, for they would vaporize in Lunar air. Grinding them up seriously, might make for pretty rings, when we determine the correct feed rate to compensate oxygen escape. Gently decaying orbits in these rings would snow imperceptibly into the upper reaches of the Lunar atmosphere. We might be able to calculate it so fine, that it would regulate the air and water for as many millenia as it matters. It's possible as far as I know, that a highly complex dynamic solution could be found, that would let the Moon's ice rings cast the periodic shadows needed for higher plants to thrive. See, you can't trick me into saying what I didn't want to mention, about what I might have in mind for the Moon! Johnny Thunderbird From VM Wed Feb 28 14:25:02 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["229" "Wednesday" "28" "February" "2001" "14:17:18" "-0800" "Steve VanDevender" "stevev@efn.org" nil "6" "Re: starship-design: Ice Impact Terraforming" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 229 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f1SMHMa12326 for starship-design-outgoing; Wed, 28 Feb 2001 14:17:22 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f1SMHLJ12317 for ; Wed, 28 Feb 2001 14:17:21 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f1SMHI025698 for ; Wed, 28 Feb 2001 14:17:19 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f1SMHJj06310; Wed, 28 Feb 2001 14:17:19 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15005.30958.382189.844895@tzadkiel.efn.org> In-Reply-To: <000501c0a1cc$8f139740$0a0a0a0a@nless> References: <000501c0a1cc$8f139740$0a0a0a0a@nless> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Ice Impact Terraforming Date: Wed, 28 Feb 2001 14:17:18 -0800 bugzapper writes: > See, you can't trick me into saying what I didn't want to mention, about > what I might have in mind for the Moon! Would that be because it would sound dangerously like the plot synopsis for "Space: 1999"? From VM Wed Feb 28 16:54:37 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["339" "Wednesday" "28" "February" "2001" "18:40:50" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "12" "Re: starship-design: Ice Impact Terraforming" "^From:" nil nil "2" nil nil nil nil nil] nil) Content-Length: 339 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f210atQ11066 for starship-design-outgoing; Wed, 28 Feb 2001 16:36:55 -0800 (PST) Received: from mail0.mco.bellsouth.net (mail0.mco.bellsouth.net [205.152.111.12]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f210arJ11058 for ; Wed, 28 Feb 2001 16:36:53 -0800 (PST) Received: from nless (adsl-20-175-67.msy.bellsouth.net [66.20.175.67]) by mail0.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id TAA02660; Wed, 28 Feb 2001 19:36:49 -0500 (EST) Message-ID: <000e01c0a1e8$4700e720$0a0a0a0a@nless> References: <000501c0a1cc$8f139740$0a0a0a0a@nless> <15005.30958.382189.844895@tzadkiel.efn.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Steve VanDevender" , "Starship Design List" Subject: Re: starship-design: Ice Impact Terraforming Date: Wed, 28 Feb 2001 18:40:50 -0600 > bugzapper writes: > > See, you can't trick me into saying what I didn't want to mention, about > > what I might have in mind for the Moon! Steve asks: > Would that be because it would sound dangerously like the plot synopsis > for "Space: 1999"? Did they want to spin up the moon's rotation 28-fold, to give it a 24-hour day? Johnny From VM Fri Mar 2 19:17:11 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2634" "Friday" "2" "March" "2001" "10:15:59" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "47" "Re: starship-design: Ice Impact Terraforming" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 2634 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f22GC5O09460 for starship-design-outgoing; Fri, 2 Mar 2001 08:12:05 -0800 (PST) Received: from mail2.mco.bellsouth.net (mail2.mco.bellsouth.net [205.152.111.14]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f22GC3J09386 for ; Fri, 2 Mar 2001 08:12:03 -0800 (PST) Received: from nless (adsl-21-216-104.msy.bellsouth.net [66.21.216.104]) by mail2.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id LAA11672 for ; Fri, 2 Mar 2001 11:02:39 -0500 (EST) Message-ID: <000b01c0a334$14d67600$0a0a0a0a@nless> References: <000501c0a1cc$8f139740$0a0a0a0a@nless> <15005.30958.382189.844895@tzadkiel.efn.org> <000e01c0a1e8$4700e720$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Ice Impact Terraforming Date: Fri, 2 Mar 2001 10:15:59 -0600 > > > See, you can't trick me into saying what I didn't want to mention, > about > > > what I might have in mind for the Moon! > Steve asks: > > Would that be because it would sound dangerously like the plot synopsis > > for "Space: 1999"? > > Did they want to spin up the moon's rotation 28-fold, to give it a 24-hour > day? Ah. My bro' reminds me "Space - 1999" was the TV series abaout a runaway moon, actually used as a planetoid type starship. Flying around in a rogue moon has never attracted me. Seems kind of extreme, an admission that the starship problem can't be solved. I think otherwise, obviously. The closest I have ever come to imagining the use of a moonlet vehicle, was when I recommended that an ice body (moonlet) might be the substance of a space ship. That was a matter of shielding, largely, and of using the ice as reaction mass. No tanks needed, when your "fuel" is a solid. This design reflected an "inexhaustable" energy criterion. Ice ships are heavy, not as much so as stony ships. But depending on how intense the radiation environment becomes, the need for shielding might turn out to be a greatly underestimated design parameter. At a guess, I don't think a few feet of lead shielding will ever be enough to let healthy humans approach the neighborhood of Jupiter, for example, particularly the Io torus. Cosmic rays, defined as near-relativistic metal nuclei, are the nastiest kind of hot. But when we start talking starships, the forward direction gets really hot in this way, as the speed of light is approached. I don't know any better answer, than to stick a lot of mass, taking up a lot of room, both before and behind the starship. Ice is about the cheapest bulky mass. Unless we have a breakthrough in the field of radiation shielding, my approach is to err on the side of caution, then double it, making all that cheap ice suddenly become very expensive. About the Moon, though. At the pool table, I have seen collisions set the three ball spinning rapidly, standing stock still on the table. I think there probably are collision solutions which will drastically affect the rotation of a large body, without appreciable damage to its orbit. The more conservative approach is to use multiple controlled strikes, tangentially at the equator, to spin up a body. A balance should be struck, between collisions which would increase the orbital velocity, approaching from behind in the orbit, and those which would slow the orbit by coming from ahead. And, no, I haven't calculated how much energy it would take, to spin up the Moon enough to make trees happy. Lots, huh? Johnny Thunderbird From VM Fri Mar 2 19:17:11 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["5185" "Friday" "2" "March" "2001" "13:29:16" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "95" "Re: starship-design: Ice Impact Terraforming" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 5185 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f22JPeh18734 for starship-design-outgoing; Fri, 2 Mar 2001 11:25:40 -0800 (PST) Received: from mail2.mco.bellsouth.net (mail2.mco.bellsouth.net [205.152.111.14]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f22JPcJ18709 for ; Fri, 2 Mar 2001 11:25:38 -0800 (PST) Received: from nless (adsl-20-175-37.msy.bellsouth.net [66.20.175.37]) by mail2.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id OAA28299 for ; Fri, 2 Mar 2001 14:15:57 -0500 (EST) Message-ID: <000f01c0a34f$1483cde0$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Ice Impact Terraforming Date: Fri, 2 Mar 2001 13:29:16 -0600 Roy Bennett writes, Isn't it true that the same area of the Moon always faces the Earth. IE it doesn't spin relative to Earth? Roy responding to my --> > About the Moon, though. At the pool table, I have seen collisions set the > three ball spinning rapidly, standing stock still on the table. I think > there probably are collision solutions which will drastically affect the > rotation of a large body, without appreciable damage to its orbit. The more > conservative approach is to use multiple controlled strikes, tangentially at > the equator, to spin up a body. A balance should be struck, between > collisions which would increase the orbital velocity, approaching from > behind in the orbit, and those which would slow the orbit by coming from > ahead. And, no, I haven't calculated how much energy it would take, to spin > up the Moon enough to make trees happy. Lots, huh? so I say, The Moon spins once a month (its orbital period) relative to the sky. (No, I won't mess with synodic and sidereal, and stuff like that. Not until I'm really ready to make the spin-up calculation.) We always see the same face of the moon, because it is "tide locked" to us, as its gravitational primary. That is a low-energy stable state, implying the Earth-Moon dynamic system is very old. The Moon had a spin when it formed, but Earth's gravitation just gradually wore down that smaller body's spin energy. The tidal force that "locks" the Moon's rotation to Earth's center of mass, is more a frictional force at high energies, but would be a temporary impediment when the speed-up was just starting. That's when you have hit the Moon's equator with just a few rocks. But after you have broken free of this initial stasis, the tidal drag wouldn't be anything you'd have to worry about, in the next few million. Fully established with a 24-hour day, you'd see half a moon rotation from Earth's surface, if the Moon was above your horizon for 12 hours. The next night, about the same, only 1/28th difference in the Lunar scenery you saw the previous night. Every month (don't ask!) you'd see everyplace on the Moon at your "lunar midnight" zenith. The phases of the Moon would look the same as they do now, if you're nearsighted as me. The surface of the Moon is the same as the land area of the continents. We would not double the area of our productive forests and farms, though, by terraforming the Moon. It would be necessary to cover about half of it with seas, to ensure thermal stability in our new biosphere. So a 50% increase in the room available to land life, is our outside limit. Every little bit helps, if you're life trying to stay alive. Mars is the biggie, that's the pie. We can't mess up on that one. Venus is a long shot. You will hear it here first, by the way; I don't know anybody else who might have made this suggestion. I keep imagining dynamic solutions. I never try to pretend my imaginings are accurate, as quantitative solutions to the relevant equations. For anybody who hates math as much as I do, my fantasies will have to serve as a surrogate for accurate knowledge. At least until I get some fancy computer programming done, to show that machines are great tools, to keep us from having to do all that uncomfortable thinking, in mathematical symbols. To me, programming is easy, but math hurts. Venus needs a radical treatment: we ought to blast its atmosphere off. The oxidized gases which comprise it, are in low energy states. Entropy got there first. We don't have any good energy leverage to use, to transform those gases to less hostile molecules. CO2 and SO2 and H2O, man, you're going nowhere with those, chemically. Blast Venus with a comet, and start over on the atmosphere building. More specifically, an exploded comet, scattered bombwise just before impact, until its impact area covers an entire hemisphere of Venus. Comets are quick. We would need a big one. We would probably need to go out in the Oort Cloud, to ship it in. That's a long trip. Meat and potatoes for us. An ice cloud which hits half of Venus, will serve an eviction notice to the nastiest atmosphere in the system. Uncle Pow, and the near side gases are pushed out to nowheresville. The noise gets around the planet pretty quick, and at the nadir the atmosphere spews up in a great fountain. You might lose 2/3 of the gases at Venus escape velocity in this impact, possibly the best we can hope for. Unless we decide to, umh, iterate, if we decide that even 1/3 of the CO2 of Venus, plus all the water vapor we just added, is still too heavy. Am I serious? Well, it would be a lot of work, terraforming Venus. We can't handle as much CO2 as there is on Venus, with any known biological, chemical, or geophysical processes. The only way to get rid of it is by violence. I eagerly advocate impact terraforming. Let's go ahead and get this business fixed, while we're still young enough to enjoy it. After Mars and the Moon, Venus is the only real estate left in the habitable thermal zone. Farm land is gold, to a humanity of large population. To expand after that, we have to go the long way. The long way, is what our correspondence is about. Johnny Thunderbird From VM Fri Mar 2 19:17:11 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["6102" "Friday" "2" "March" "2001" "14:22:55" "-0800" "N. Lindberg" "nlindber@u.washington.edu" nil "139" "starship-design: X-33 Cancelled, " "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 6102 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f22MMvB26114 for starship-design-outgoing; Fri, 2 Mar 2001 14:22:57 -0800 (PST) Received: from jason01.u.washington.edu (root@jason01.u.washington.edu [140.142.8.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f22MMuJ26100 for ; Fri, 2 Mar 2001 14:22:56 -0800 (PST) Received: from dante05.u.washington.edu (nlindber@dante05.u.washington.edu [140.142.15.7]) by jason01.u.washington.edu (8.9.3+UW00.05/8.9.3+UW00.12) with ESMTP id OAA46812 for ; Fri, 2 Mar 2001 14:22:55 -0800 Received: from localhost (nlindber@localhost) by dante05.u.washington.edu (8.9.3+UW00.05/8.9.3+UW00.12) with ESMTP id OAA28144 for ; Fri, 2 Mar 2001 14:22:55 -0800 Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Precedence: bulk Reply-To: "N. Lindberg" From: "N. Lindberg" Sender: owner-starship-design@lists.uoregon.edu To: starship design Subject: starship-design: X-33 Cancelled, Date: Fri, 2 Mar 2001 14:22:55 -0800 (PST) hello all, i just got this off the space.com website. Here's a copy ************************************** WASHINGTON -- NASA announced Thursday that the problem-plagued X-33 spaceplane project, a venture that aimed to create a single-stage-to-orbit spaceliner, has been scrapped. In addition, the American space agency announced that another reusable rocket, the X-34, is being axed. In total, these NASA resolutions add up to over $1 billion worth of canceled projects. Related X-33 Multimedia 3-D X-33:Navigate around the X-33 spacecraft.ACTIVATE "Obviously, there's a lot of disappointed folks, and I'm one of them," said Arthur Stephenson, director of NASA's Marshall Space Flight Center in Huntsville, Alabama. The center is NASA's lead work force in creating vehicles for routine and low-cost access to space. SLI funding Stephenson said that NASA will not add funds to the X-33 or X-34 programs from money dedicated to the agency's Space Launch Initiative (SLI). NASA's SLI is designed to push forward technology development for concepts that would be able to launch payloads for NASA, commercial and military missions, as well as fly crews to and from the International Space Station. The decision by NASA Thursday terminates work on the X-33, a cooperative project between NASA and the lead industrial partner for the project, the Lockheed Martin Aeronautics Company, Stephenson said. The X-34 contract will expire, and rocket builder Orbital Sciences Corporation of Dulles, Virginia was notified of the decision, Stephenson said. NASA has spent to date $912 million on the X-33, with another $205 million expended on the X-34 project. In the case of the X-33, Lockheed Martin had invested $356 million of its own monies in the effort to create a single-stage-to-orbit vehicle, Stephenson said. "I hate to see us not be able to go forward and complete these programs. But we have to make good decisions fiscally, and be responsible in picking those activities that can give us the greatest benefit. And flying these vehicles turned out not to warrant the magnitude of the cost involved," Stephenson said. The decision to terminate both X-33 and X-34 were made internally by NASA and were not a White House decision, Stephenson said. The X-34 program was initiated in 1996. It was to provide a low-cost technology test bed that would demonstrate a streamlined management approach with a rapid development schedule and limited testing. A review by NASA and Orbital Sciences found the projected cost of completing the X-34 had hit unacceptable levels and incurred too much technical risk. Trouble plagued Troubled by technical snags, the X-33 rocket plane project, an effort to spark creation of a commercial single-stage-to-orbit vehicle, has been the topic of intense renegotiations between NASA and the lead industrial partner for the project, the Lockheed Martin Aeronautics Company. Unveiled in July 1996 by then U.S. Vice President Al Gore and still-on-assignment NASA Administrator, Daniel Goldin, the pilotless X-33 was slated to rocket skyward on the first of a series of suborbital test hops three years later. The X-33 design is based on a lifting-body shape with two novel "linear aerospike" rocket engines and a rugged metallic thermal protection system. The X-33 also features lightweight components and fuel tanks built to conform to the vehicle's outer shape. On February 6, tandem aerospike engines were test fired for the first time at NASA's John C. Stennis Space Center in Bay St. Louis, Mississippi. That blast went the full scheduled duration of 1.1 seconds with no observed anomalies. Eight more test firings of the twin-flight engines were planned at Stennis before they were to be delivered to Lockheed Martin's X-33 assembly facility in Palmdale, California. The qualification test firings of the unique engines for the spaceplane were to lead to the first high-speed, suborbital flight sometime in 2003. NASA and Lockheed Martin jointly own the launch site for X-33 at Edwards Air Force Base, along with the vehicle. "We'll be looking at what's the best use of that launch site. I don't have a good answer to that at this point," Stephenson told SPACE.com. In a statement, Rep. Dana Rohrabacher (R-California), chairman of the House Science Space and Aeronautics Subcommittee, applauded NASA's decision to terminate the X-33 and X-34 programs. "I'm very happy to see that SLI is back on track advancing the national launch capability. The decision to terminate the X-33 and X-34 sends the signal that we expect corporate commitments to be kept. Out the window The X-33 experimental vehicle ran into myriad technical woes, tossing time schedules for getting the spaceplane airborne out the window. Building the X-33 had proven far from trouble free. Stability of the sleek looking wedge-shaped craft at various speed ranges, as well as its overall weight, has plagued designers. Novel "linear aerospike" engines that would have powered the rocket plane also proved troublesome to build. In November 1999, an X-33 composite liquid-hydrogen tank ran into difficulty while undergoing tests at NASA's Marshall Space Flight Center. Long considered a major engineering hurdle, the tank lived up to that reputation, causing a major launch slip and forcing NASA and Lockheed Martin to take a second look at the entire program. For Lockheed Martin, lessons learned in building and flying X-33 were seen key to validating new technologies and reducing risk for the commercial VentureStar -- the firm's fully reusable, single-stage-to-orbit vehicle. "Getting to a single-stage-to-orbit was viewed as being very difficultand it's still viewed as very difficult," Stephenson said. "What we're hearing from industry and our own evaluation is that we believe a single-stage-to-orbit vehicle for a second-generation vehicle [a follow-on to the space shuttle] is not viable at this time. We are focusing on multi-stage, beginning with a two-stage vehicle," Stephenson said. Brian Berger and Stew Magnuson of Space News contributed to this report. From VM Fri Mar 2 19:17:11 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["668" "Friday" "2" "March" "2001" "19:50:11" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "16" "Re: starship-design: X-33 Cancelled," "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 668 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f230oSf06122 for starship-design-outgoing; Fri, 2 Mar 2001 16:50:28 -0800 (PST) Received: from imo-r18.mx.aol.com (imo-r18.mx.aol.com [152.163.225.72]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f230oRJ06107 for ; Fri, 2 Mar 2001 16:50:27 -0800 (PST) Received: from KellySt@aol.com by imo-r18.mx.aol.com (mail_out_v29.5.) id z.71.b329026 (16492) for ; Fri, 2 Mar 2001 19:50:11 -0500 (EST) Message-ID: <71.b329026.27d199c3@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: X-33 Cancelled, Date: Fri, 2 Mar 2001 19:50:11 EST In a message dated 3/2/01 4:24:20 PM, nlindber@u.washington.edu writes: >hello all, i just got this off the space.com website. Here's a copy >************************************** > > >WASHINGTON -- NASA announced Thursday that the problem-plagued X-33 >spaceplane project, a venture that aimed to create a single-stage-to-orbit >spaceliner, has been scrapped. == This is really good news. X-33 & X-34 canceled, George Abbey flushed out of JSC, Statin caped. The Bush admin is making Goldin clean up the mess he made before he leaves, and they are directing him to take out exactly whats strangling NASA most. This is much better then I expected so soon! From VM Mon Mar 5 10:24:00 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2672" "Sunday" "4" "March" "2001" "20:50:05" "-0800" "Steve VanDevender" "stevev@efn.org" nil "44" "Re: starship-design: Ice Impact Terraforming" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 2672 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f254oUK09805 for starship-design-outgoing; Sun, 4 Mar 2001 20:50:30 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f254oTJ09790 for ; Sun, 4 Mar 2001 20:50:29 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f254oRn02345 for ; Sun, 4 Mar 2001 20:50:28 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f254oGo24663; Sun, 4 Mar 2001 20:50:16 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15011.6909.649322.806385@tzadkiel.efn.org> In-Reply-To: <000b01c0a334$14d67600$0a0a0a0a@nless> References: <000501c0a1cc$8f139740$0a0a0a0a@nless> <15005.30958.382189.844895@tzadkiel.efn.org> <000e01c0a1e8$4700e720$0a0a0a0a@nless> <000b01c0a334$14d67600$0a0a0a0a@nless> X-Mailer: VM 6.91 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Ice Impact Terraforming Date: Sun, 4 Mar 2001 20:50:05 -0800 bugzapper writes: > Ah. My bro' reminds me "Space - 1999" was the TV series abaout a runaway > moon, actually used as a planetoid type starship. Flying around in a rogue > moon has never attracted me. Seems kind of extreme, an admission that the > starship problem can't be solved. I think otherwise, obviously. In "Space: 1999" the moon wasn't _meant_ to be a starship, but it got blown out of orbit by an explosion in a nuclear waste dump on the far side (I think they even went so far, in their lack of attention to physics and astronomy, as to call it the "dark side" of the moon). This was, of course, wildly implausible. It was also wildly implausible that the inhabitants of Moonbase Alpha managed to visit many distant solar systems within a relatively short time. I remember that it was great fun when I watched it as a ten-year-old, but I was no more seriously proposing turning the moon into a starship than you were. > About the Moon, though. At the pool table, I have seen collisions set the > three ball spinning rapidly, standing stock still on the table. I think > there probably are collision solutions which will drastically affect the > rotation of a large body, without appreciable damage to its orbit. The more > conservative approach is to use multiple controlled strikes, tangentially at > the equator, to spin up a body. A balance should be struck, between > collisions which would increase the orbital velocity, approaching from > behind in the orbit, and those which would slow the orbit by coming from > ahead. And, no, I haven't calculated how much energy it would take, to spin > up the Moon enough to make trees happy. Lots, huh? And speaking of the wildly implausible . . . Let's put it this way. Moons and planets aren't billiard balls. Most importantly, billiard balls are far more rigid and internally cohesive than any planet. Think of trying to do this with balls of damp sand; on a planetary scale, that's about how cohesive a planet is. You might be able to impart some angular momentum to the Moon by smacking it with another Moon-sized object, but you're going to end up with a spinning collection of very small rocks, not a neat glancing collision that leaves both bodies whole and one of them spinning nicely. Trying to spin up the Moon with tangential comet impacts at its equator is also wildly implausible. The comets aren't going to impart much angular momentum, for one thing; they'll just chip off bits of Moon that will spray into space. Even if you have all the comets you want, after a while you'll only end up with a Moon shaped vaguely like an apple core that won't be spinning much faster. From VM Mon Mar 5 15:11:26 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["3303" "Monday" "5" "March" "2001" "17:07:58" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "59" "Re: starship-design: Ice Impact Terraforming" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 3303 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f25N41n09836 for starship-design-outgoing; Mon, 5 Mar 2001 15:04:01 -0800 (PST) Received: from mail2.mco.bellsouth.net (mail2.mco.bellsouth.net [205.152.111.14]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f25N3wJ09813 for ; Mon, 5 Mar 2001 15:03:58 -0800 (PST) Received: from nless (adsl-20-175-124.msy.bellsouth.net [66.20.175.124]) by mail2.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id RAA21547 for ; Mon, 5 Mar 2001 17:54:28 -0500 (EST) Message-ID: <001f01c0a5c9$24d32200$0a0a0a0a@nless> References: <000501c0a1cc$8f139740$0a0a0a0a@nless><15005.30958.382189.844895@tzadkiel.efn.org><000e01c0a1e8$4700e720$0a0a0a0a@nless><000b01c0a334$14d67600$0a0a0a0a@nless> <15011.6909.649322.806385@tzadkiel.efn.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Ice Impact Terraforming Date: Mon, 5 Mar 2001 17:07:58 -0600 From: "Steve VanDevender" > And speaking of the wildly implausible . . . > > Let's put it this way. Moons and planets aren't billiard balls. Most > importantly, billiard balls are far more rigid and internally cohesive > than any planet. Think of trying to do this with balls of damp sand; on > a planetary scale, that's about how cohesive a planet is. You might be > able to impart some angular momentum to the Moon by smacking it with > another Moon-sized object, but you're going to end up with a spinning > collection of very small rocks, not a neat glancing collision that > leaves both bodies whole and one of them spinning nicely. > > Trying to spin up the Moon with tangential comet impacts at its equator > is also wildly implausible. The comets aren't going to impart much > angular momentum, for one thing; they'll just chip off bits of Moon that > will spray into space. Even if you have all the comets you want, after > a while you'll only end up with a Moon shaped vaguely like an apple core > that won't be spinning much faster. > Hmm - the direct dynamic solution would be my preference, as a way to spin up a "solid" body. That's because it is quickest, if the task could be done that way. There is a solution by gravitational interaction, involving a large gravitational body in elliptical orbit around the Moon, which would take longer, but would unquestionably spin up rotation. Farther afield, we could find electromagnetic solutions, though most such would need large scale machinery construction. But back to hitting it with rocks: the impactors are very small compared to the Moon, order of 1-10 km diameter. The impact trajectory is neither precisely tangential, nor precisely equatorial. Impacts all have a vector component of force which can be translated into a contribution to the Moon's angular momentum. The most effective momentum transfer isn't when the impactor skips off the surface and escapes, but when its mass is absorbed. Ejecta are not required, for momentum transfer of the impacting body, into angular momentum of the target body. Ejecta escaping make litter. Your examples of eroding the Moon away, relate to impact velocities too high to do the job. If anything chips off the Moon, and escapes in the direction the impactor was going, its momentum is wasted because it did not contribute to spinning up the Moon. For impacts of useful energy, a mountain range, cliff or crater wall should make a good backstop for low-angle impacts. Whether the impacting bodies are ice, metal, or rock isn't relevant to momentum transfer, as long as nothing escapes forward. Every impactor which hits and is completely absorbed, at any angle other than vertical, exerts a moment of torque on the Moon. Horizontal absorbtion at the Equator is the extreme limiting case, of the most efficient momentum transfer of the impacting body, to angular momentum of the Moon as target body. No actual strike will be exactly horizontal, but will be angled down to such a degree as to ensure that ejecta do not escape. If impact speeds are effectively moderated that no ejecta escape, the physical properties of the target body are not relevant to its inertial relationships. If torque is applied to a body made of powder, it will spin. Johnny Thunderbird From VM Mon Mar 5 16:04:10 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["4232" "Monday" "5" "March" "2001" "18:55:10" "-0500" "Curtis Manges" "curtismanges@netscape.net" nil "78" "[Fwd: Re: starship-design: Ice Impact Terraforming]" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 4232 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f25Nt5r09023 for starship-design-outgoing; Mon, 5 Mar 2001 15:55:05 -0800 (PST) Received: from imo-m09.mx.aol.com (imo-m09.mx.aol.com [64.12.136.164]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f25Nt3J09004 for ; Mon, 5 Mar 2001 15:55:03 -0800 (PST) Received: from curtismanges@netscape.net by imo-m09.mx.aol.com (mail_out_v29.5.) id z.1b.1011892 (16227) for ; Mon, 5 Mar 2001 18:54:47 -0500 (EST) Received: from netscape.com (aimmail09.aim.aol.com [205.188.144.201]) by air-in02.mx.aol.com (v77_r1.21) with ESMTP; Mon, 05 Mar 2001 18:54:47 -0500 Mime-Version: 1.0 Message-ID: <36D34CF1.090BB287.74D2F445@netscape.net> X-Mailer: Franklin Webmailer 1.0 Content-Type: text/plain; charset="ISO-8859-1" Precedence: bulk Reply-To: curtismanges@netscape.net (Curtis Manges) From: curtismanges@netscape.net (Curtis Manges) Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: [Fwd: Re: starship-design: Ice Impact Terraforming] Date: Mon, 05 Mar 2001 18:55:10 -0500 Just a thought, but what if your impactors were made of something like bubble gum? You could fire those in at a very shallow trajectory without having to worry about losing mass as ejecta. keep looking up, Curtis -------- Original Message -------- Subject: Re: starship-design: Ice Impact Terraforming Date: Mon, 5 Mar 2001 17:07:58 -0600 From: "bugzapper" Reply-To: "bugzapper" To: "Starship Design List" References: <000501c0a1cc$8f139740$0a0a0a0a@nless><15005.30958.382189.844895@tzadkiel.efn.org><000e01c0a1e8$4700e720$0a0a0a0a@nless><000b01c0a334$14d67600$0a0a0a0a@nless> <15011.6909.649322.806385@tzadkiel.efn.org> From: "Steve VanDevender" > And speaking of the wildly implausible . . . > > Let's put it this way.  Moons and planets aren't billiard balls.  Most > importantly, billiard balls are far more rigid and internally cohesive > than any planet.  Think of trying to do this with balls of damp sand; on > a planetary scale, that's about how cohesive a planet is.  You might be > able to impart some angular momentum to the Moon by smacking it with > another Moon-sized object, but you're going to end up with a spinning > collection of very small rocks, not a neat glancing collision that > leaves both bodies whole and one of them spinning nicely. > > Trying to spin up the Moon with tangential comet impacts at its equator > is also wildly implausible.  The comets aren't going to impart much > angular momentum, for one thing; they'll just chip off bits of Moon that > will spray into space.  Even if you have all the comets you want, after > a while you'll only end up with a Moon shaped vaguely like an apple core > that won't be spinning much faster. > Hmm - the direct dynamic solution would be my preference, as a way to spin up a "solid" body. That's because it is quickest, if the task could be done that way. There is a solution by gravitational interaction, involving a large gravitational body in elliptical orbit around the Moon, which would take longer, but would unquestionably spin up rotation. Farther afield, we could find electromagnetic solutions, though most such would need large scale machinery construction. But back to hitting it with rocks: the impactors are very small compared to the Moon, order of 1-10 km diameter. The impact trajectory is neither precisely tangential, nor precisely equatorial. Impacts all have a vector component of force which can be translated into a contribution to the Moon's angular momentum. The most effective momentum transfer isn't when the impactor skips off the surface and escapes, but when its mass is absorbed. Ejecta are not required, for momentum transfer of the impacting body, into angular momentum of the target body. Ejecta escaping make litter. Your examples of eroding the Moon away, relate to impact velocities too high to do the job. If anything chips off the Moon, and escapes in the direction the impactor was going, its momentum is wasted because it did not contribute to spinning up the Moon. For impacts of useful energy, a mountain range, cliff or crater wall should make a good backstop for low-angle impacts. Whether the impacting bodies are ice, metal, or rock isn't relevant to momentum transfer, as long as nothing escapes forward. Every impactor which hits and is completely absorbed, at any angle other than vertical, exerts a moment of torque on the Moon. Horizontal absorbtion at the Equator is the extreme limiting case, of the most efficient momentum transfer of the impacting body, to angular momentum of the Moon as target body. No actual strike will be exactly horizontal, but will be angled down to such a degree as to ensure that ejecta do not escape. If impact speeds are effectively moderated that no ejecta escape, the physical properties of the target body are not relevant to its inertial relationships. If torque is applied to a body made of powder, it will spin. Johnny Thunderbird __________________________________________________________________ Get your own FREE, personal Netscape Webmail account today at http://webmail.netscape.com/ From VM Mon Mar 5 18:10:56 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1108" "Monday" "5" "March" "2001" "18:03:11" "-0800" "Steve VanDevender" "stevev@efn.org" nil "21" "Re: starship-design: Ice Impact Terraforming" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1108 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2623Ph13597 for starship-design-outgoing; Mon, 5 Mar 2001 18:03:25 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2623NJ13567 for ; Mon, 5 Mar 2001 18:03:23 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f2623Mn11075 for ; Mon, 5 Mar 2001 18:03:22 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f2623DW27102; Mon, 5 Mar 2001 18:03:13 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15012.17759.911679.37193@tzadkiel.efn.org> In-Reply-To: <001f01c0a5c9$24d32200$0a0a0a0a@nless> References: <000501c0a1cc$8f139740$0a0a0a0a@nless> <15005.30958.382189.844895@tzadkiel.efn.org> <000e01c0a1e8$4700e720$0a0a0a0a@nless> <000b01c0a334$14d67600$0a0a0a0a@nless> <15011.6909.649322.806385@tzadkiel.efn.org> <001f01c0a5c9$24d32200$0a0a0a0a@nless> X-Mailer: VM 6.91 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Ice Impact Terraforming Date: Mon, 5 Mar 2001 18:03:11 -0800 bugzapper writes: > If impact speeds are effectively moderated that no ejecta escape, the > physical properties of the target body are not relevant to its inertial > relationships. If torque is applied to a body made of powder, it will spin. If the impact speeds are low enough to avoid blowing ejecta into space, then the mass of impactors needed to substantially increase the Moon's rotational rate will be a substantial fraction of the Moon's mass. If the impact speeds are higher, then you'll mostly blow a lot of energy throwing ejecta into space and heating the lunar surface without affecting its rotation substantially. As it is the existing rotation of planets is left over from their formation, and has not been substantially affected by any subsequent impacts. In some cases tidal coupling (such as between Earth and its Moon or Jupiter and its inner moons) has produced resonance -- over billions of years. Probably the biggest problem with terraforming Venus is not making the atmosphere breathable, but changing Venus's rotation rate into something that will produce tolerable weather. From VM Mon Mar 5 18:19:28 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["654" "Monday" "5" "March" "2001" "18:14:50" "-0800" "Steve VanDevender" "stevev@efn.org" nil "12" "[Fwd: Re: starship-design: Ice Impact Terraforming]" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 654 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f262F3s27225 for starship-design-outgoing; Mon, 5 Mar 2001 18:15:03 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f262F2J27218 for ; Mon, 5 Mar 2001 18:15:02 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f262F0n12816 for ; Mon, 5 Mar 2001 18:15:00 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f262EpY27131; Mon, 5 Mar 2001 18:14:51 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15012.18458.47864.694344@tzadkiel.efn.org> In-Reply-To: <36D34CF1.090BB287.74D2F445@netscape.net> References: <36D34CF1.090BB287.74D2F445@netscape.net> X-Mailer: VM 6.91 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: [Fwd: Re: starship-design: Ice Impact Terraforming] Date: Mon, 5 Mar 2001 18:14:50 -0800 Curtis Manges writes: > Just a thought, but what if your impactors were made of something > like bubble gum? You could fire those in at a very shallow trajectory > without having to worry about losing mass as ejecta. I'm not sure what you're thinking here, but I'm not sure you can make anything that acts like "bubble gum" at high impact velocities. Pretty much any reasonable material I can imagine will be deformed and heated to liquefaction or vaporization by high-speed impact. And even if the stuff you impact with is "sticky", you can't depend on the lunar surface sticking to it; the shock wave from the impact will kick up lots of debris. From VM Tue Mar 6 10:14:28 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["4726" "Tuesday" "6" "March" "2001" "04:09:34" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "88" "starship-design: Fusion Cone Scoop" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 4726 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f26A6Pl14386 for starship-design-outgoing; Tue, 6 Mar 2001 02:06:25 -0800 (PST) Received: from mail0.mco.bellsouth.net (mail0.mco.bellsouth.net [205.152.111.12]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f26A6OJ14368 for ; Tue, 6 Mar 2001 02:06:24 -0800 (PST) Received: from nless (adsl-20-175-124.msy.bellsouth.net [66.20.175.124]) by mail0.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id FAA04232 for ; Tue, 6 Mar 2001 05:06:22 -0500 (EST) Message-ID: <000d01c0a625$8e2a1fe0$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: starship-design: Fusion Cone Scoop Date: Tue, 6 Mar 2001 04:09:34 -0600 The accelerators we are familiar with, produce a concentrated linear beam, a ray. If we could spread out our beam of accelerated particles, in a surface of conical shape, each particle trajectory deflected by the same angle, we could build a cone of accelerated particles. Made with light ions, this cone, open forward, traverses space with the ship. Diffuse nuclear fusion reactions occur, as the accelerated particles collide with particles of the interstellar medium. Fusion pushes, as do all energy-releasing processes. The cone of fusion traversing forward establishes a shock front, which pushes progressively inward on both neutral gas and plasma, to serve as an effective ram scoop. Though drag forces may occur on the ship, in its own interaction with the medium, this drag is proportional to the ship's cross sectional area, straight hydrodynamics. No back pressure is felt by the accelerator, from remote fusion events many kilometers down its beam. So no drag forces are due to the compression event, but all retarding forces are from direct interactions of the ship with the onrushing column of gas. Producing the cone by sending out light ions forward gives a decelerating force, but (hopefully) this may be negligible compared to the chemical energy released. I think I'm on the trail of a straightforward ram scoop design. It hinges on a lot of presumptive physics, though. My guesses, about might happen in physics under exotic circumstances, should be treated as such, and carefully examined by anyone who knows better. 1) A high energy beam, of light ions, will produce diffuse, energy-releasing fusion reactions as it traverses the sparse interstellar hydrogen gas. 2) The ion beam sheet, formed into a cone, will, by remote induced nuclear fusion, mechanically compress the interstellar gas into a jet, directed at the bow of the starship. 3) The approaching column of gas, in laminar flow, is yet too sparse to recombine chemically, until its periphery is further ionized, by electron beam (or whatever's handy.) 4) This sheath of plasma, surrounding the neutral gas jet, is further compressed magnetically, compressing its contained neutral gas. 5) In this final compression, the local atomic hydrogen achieves chemical recombination. It burns. ---- So a fusion scoop can power a chemical rocket! That's the basic plan. At least the following bolt-on accessories should be considered: 6) A magnetic field, transverse to the flame, gives mass spectroscopic separation of ions heavier than helium. The other way, deflected electrons give MHD power for the ship. 7) Metals scavenged, an adjustment field of opposite polarity realigns hydrogen and helium ions. These tend to diverge in the mass spectroscopy field, from the neutral jet, so are turned back to it between these poles. 8) These "sideways" pole pairs are followed by a magnetic coil which actually loops the flame, making a virtual nozzle throat, with field lines on-axis to the flame, for increased collimation. 9) The fusion booster is just your plain old chemical rocket, 1 through 5 above, with a power package in a long pipe, which surrounds your rocket flame. Inside the ship is a cyclotron, which boosts lithium ions and ships them down through the pipe. A certain fraction of them collide with protons and produce fusion within the pipe. The heat captured by the pipe is used in a heat engine, to provide power to the ship. 10) The top of the line version, uses all of the above just as a power source. Pure "cold" protons (those with thermal energies, not having been involved in fusion reactions) are diverted out into the tuned linac. This machine is made of metal and kept cold, to provide the main reaction engine in relativistic regimes. 11) Rotating steel ring magnets, "zero-pole" because their magnetic circuits are complete, may store energy by spinning within cryogenic magnet coils. The coil is a torus, helix-wound of high field Type II superconductor like magnesium boride http://superconductors.org/39K.htm or niobium silicide. The winding form may be of glass or ceramic, evacuated. Standing wave modulations imposed on the DC magnet current will rotate the ring when their phase is advanced, storing energy, or decelerate it when their phase is retarded. The current induced in the winding when the ring is slowed, may be tapped off to provide ship's power. (Talk about trouble getting turned around, these you just won't get turned. They are far too good as gyroscopes. That's a complication.) The advanced machinery items, of suggestions 6-11, are not essential components of the fusion ramscoop chemical rocket, which is described in 1-5. I put them in because I couldn't help it. Johnny Thunderbird From VM Tue Mar 6 10:14:28 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1038" "Tuesday" "6" "March" "2001" "04:33:41" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "28" "Re: starship-design: Ice Impact Terraforming" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1038 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f26AUXC07444 for starship-design-outgoing; Tue, 6 Mar 2001 02:30:33 -0800 (PST) Received: from mail1.mco.bellsouth.net (mail1.mco.bellsouth.net [205.152.111.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f26AUVJ07421 for ; Tue, 6 Mar 2001 02:30:31 -0800 (PST) Received: from nless (adsl-20-175-124.msy.bellsouth.net [66.20.175.124]) by mail1.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id FAA15079 for ; Tue, 6 Mar 2001 05:30:30 -0500 (EST) Message-ID: <001701c0a628$ecaf7bc0$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Ice Impact Terraforming Date: Tue, 6 Mar 2001 04:33:41 -0600 Roy Bennett writes: Why spin it up at all? Couldn't you just use a system of reflectors in orbit to light up the surface? It would be a lot easier. Even if you do, though, I doubt if the Moon has enough gravity to hold on to an atmosphere for very long Roy ------ If you spin it up, it's permanent. More so than the atmosphere, which has a half life on the order of millenia. The only reference I have seen said 4000 years, but this may be the period of substantially complete loss rather than the half life. We don't need it to hold on to an atmosphere for very long in astrophysical terms, just in human terms. The tricks with mirrors and shades seem fragile and impermanent. This calls for very large scale construction with metal foil. With air on the Moon, I am afraid high winds will accompany every light to shade edge. If it works, I'm for it. Spinning it up would be a more elegant solution, but until I can get Steve some numbers, he'll remain doubtful. I need to learn Matlab, put it off long enough. Johnny Thunderbird From VM Tue Mar 6 10:14:28 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1884" "Tuesday" "6" "March" "2001" "09:50:10" "-0800" "Steve VanDevender" "stevev@efn.org" nil "33" "starship-design: Fusion Cone Scoop" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1884 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f26HoXS20024 for starship-design-outgoing; Tue, 6 Mar 2001 09:50:33 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f26HoWp20015 for ; Tue, 6 Mar 2001 09:50:32 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f26HoTn18099; Tue, 6 Mar 2001 09:50:30 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f26HoJ131182; Tue, 6 Mar 2001 09:50:19 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15013.9042.763055.519045@tzadkiel.efn.org> In-Reply-To: <000d01c0a625$8e2a1fe0$0a0a0a0a@nless> References: <000d01c0a625$8e2a1fe0$0a0a0a0a@nless> X-Mailer: VM 6.91 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "bugzapper" Cc: "Starship Design List" Subject: starship-design: Fusion Cone Scoop Date: Tue, 6 Mar 2001 09:50:10 -0800 bugzapper writes: > If we could spread out our beam of accelerated particles, in a surface > of conical shape, each particle trajectory deflected by the same angle, we > could build a cone of accelerated particles. Which will generate a substantial amount of thrust -- backwards. > The cone of fusion traversing forward establishes a shock front, which > pushes progressively inward on both neutral gas and plasma, to serve as an > effective ram scoop. Though drag forces may occur on the ship, in its own > interaction with the medium, this drag is proportional to the ship's cross > sectional area, straight hydrodynamics. No back pressure is felt by the > accelerator, from remote fusion events many kilometers down its beam. So no > drag forces are due to the compression event, but all retarding forces are > from direct interactions of the ship with the onrushing column of gas. Generating the conical particle beam is retarding force enough. > Producing the cone by sending out light ions forward gives a decelerating > force, but (hopefully) this may be negligible compared to the chemical > energy released. You're trying to reach relativistic speeds with _chemical_ reactions? Pardon me, but ha ha ha ha ha ha ha. It's difficult enough, in terms of fuel-to-payload ratio, to use fusion to reach even low relativistic speeds; with fusion fuel you're looking at very roughly 10^6:1 fuel:payload. You're talking about reactions that are several orders of magnitude less efficient at mass-energy conversion, which means more orders of magnitude increase in the fuel-to-payload ratio. Even your wildly optimistic estimates of interstellar gas density won't get you enough hydrogen to boost a ship by chemically reacting the hydrogen, nor will you get enough forward thrust to overcome the backwards thrust you're generating with your conical particle beam. From VM Tue Mar 6 12:21:20 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["4028" "Tuesday" "6" "March" "2001" "14:14:14" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "80" "Re: starship-design: Fusion Cone Scoop" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 4028 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f26KBbu11034 for starship-design-outgoing; Tue, 6 Mar 2001 12:11:37 -0800 (PST) Received: from mail2.mco.bellsouth.net (mail2.mco.bellsouth.net [205.152.111.14]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f26KBZp11027 for ; Tue, 6 Mar 2001 12:11:35 -0800 (PST) Received: from nless (adsl-20-175-88.msy.bellsouth.net [66.20.175.88]) by mail2.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id PAA21711 for ; Tue, 6 Mar 2001 15:02:05 -0500 (EST) Message-ID: <000b01c0a67a$0b14b020$0a0a0a0a@nless> References: <000d01c0a625$8e2a1fe0$0a0a0a0a@nless> <15013.9042.763055.519045@tzadkiel.efn.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Fusion Cone Scoop Date: Tue, 6 Mar 2001 14:14:14 -0600 Steve laughs at: > > a cone of accelerated particles. > > Which will generate a substantial amount of thrust -- backwards. Yeah, sure will. > > direct interactions of the ship with the onrushing column of gas. > > Generating the conical particle beam is retarding force enough. It might be, but it isn't sure to be. My LINAC beam, exiting straight out the back and intended to provide thrust, is a beam made of protons that we have stepped on hard. We want to give them the largest relativistic mass multiplication factor we can, so they will have great inertia, so we can have the momentum transfer benefits of throwing out a lot heavier jet of exhaust than that much hydrogen would seem to weigh, in a balloon at 1g. This beam meant for propulsion, is discharged from a machine we have tuned to give them the maximum possible acceleration, for the energy we can afford. But nuclear fusion does not require such a hard impact. With the ramscoop beam, we are not trying to make a proton weigh a pound. We need a high current, true, to assure the density of our cone wall close to the ship. We don't have to send these particles out so darn fast. We don't want to affect an unlimited region of space. Our cone boundary is limited by dissipation, as the final errant particles meet their space resident proton and flare in fusion. Relative to "cold" space gas, the immediate velocity of the ship which projects the particles is added to the speed at which they're shot. The particles of the cone beam do not need relativistic speeds at all. Just throwing them over the side, at the ship's speed, is fast enough to generate nuclear fusion. Our need to give them speed, is so they will travel a long way to gain us lots of gas, but that doesn't mean they need to get near the speed of light. If it can be adequately collimated, a single stage of electrostatic acceleration might be adequate to project this cone. > > Producing the cone by sending out light ions forward gives a decelerating > > force, but (hopefully) this may be negligible compared to the chemical > > energy released. > > You're trying to reach relativistic speeds with _chemical_ reactions? > Pardon me, but ha ha ha ha ha ha ha. It's difficult enough, in terms of > fuel-to-payload ratio, to use fusion to reach even low relativistic > speeds; with fusion fuel you're looking at very roughly 10^6:1 > fuel:payload. You're talking about reactions that are several orders of > magnitude less efficient at mass-energy conversion, which means more > orders of magnitude increase in the fuel-to-payload ratio. Look closer: how much of this fuel am I carrying? None, right? What does that make the ratio? It would be fine to keep a 1:1, or even a 10:1 ice ratio aboard, for shielding, but it isn't needed for fuel. Hydrogen can be harvested any time from the rushing stream about. > Even your > wildly optimistic estimates of interstellar gas density won't get you > enough hydrogen to boost a ship by chemically reacting the hydrogen, nor > will you get enough forward thrust to overcome the backwards thrust > you're generating with your conical particle beam. You didn't name the real problem this time, but you get credit anyway, because I've seen you mention it before. The real problem is exhaust velocity. Even the best chemical reaction, which is this one, gives a lousy exhaust velocity. Fusion does a lot better, by stepping out of the thermal mode for excitation of its exhaust particles, but not even fusion ash particles approach lightspeed. Antimatter is too costly. What you're left with is an accelerator or an electromagnetic (light) beam. I'll take matter, because it's heavier, not because it's darker. Gulping umpteen cubic kilometers of nearly nothing, seems like it might get you something. You're harvesting the stuff real fast. I offered a scoop proposal which isn't drag-limited, and it doesn't have any real constraints on the area (volume) harvested. If there's anything out there, this will get it. Johnny Thunderbird From VM Tue Mar 6 14:02:57 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["4120" "Tuesday" "6" "March" "2001" "12:43:49" "-0800" "Steve VanDevender" "stevev@efn.org" nil "71" "Re: starship-design: Fusion Cone Scoop" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 4120 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f26Ki5c27695 for starship-design-outgoing; Tue, 6 Mar 2001 12:44:05 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f26Ki4p27690 for ; Tue, 6 Mar 2001 12:44:04 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f26Ki1n26481 for ; Tue, 6 Mar 2001 12:44:01 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f26Khox31565; Tue, 6 Mar 2001 12:43:50 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15013.19461.548413.939470@tzadkiel.efn.org> In-Reply-To: <000b01c0a67a$0b14b020$0a0a0a0a@nless> References: <000d01c0a625$8e2a1fe0$0a0a0a0a@nless> <15013.9042.763055.519045@tzadkiel.efn.org> <000b01c0a67a$0b14b020$0a0a0a0a@nless> X-Mailer: VM 6.91 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Fusion Cone Scoop Date: Tue, 6 Mar 2001 12:43:49 -0800 bugzapper writes: > > > direct interactions of the ship with the onrushing column of gas. > > > > Generating the conical particle beam is retarding force enough. > > It might be, but it isn't sure to be. My LINAC beam, exiting straight out > the back and intended to provide thrust, is a beam made of protons that we > have stepped on hard. We want to give them the largest relativistic mass > multiplication factor we can, so they will have great inertia, so we can > have the momentum transfer benefits of throwing out a lot heavier jet of > exhaust than that much hydrogen would seem to weigh, in a balloon at 1g. > This beam meant for propulsion, is discharged from a machine we have tuned > to give them the maximum possible acceleration, for the energy we can > afford. But that energy still has to come from somewhere, and you have to get enough energy to make this work. You can't accelerate your proton beam to high relativistic speeds without acquiring several times more energy than the mass of the protons. If you're pulling in fuel for nuclear fusion, that means pulling in several hundred times as much interstellar hydrogen as will go into the proton beam. Pulling that hydrogen in will induce drag; if your forward conical beam succeeds in putting a concentrated stream of hydrogen in front of your ship, then you've just shifted the location of the drag from the cone to the ship, as now the ship is encountering that denser concentrated stream of gas. It's not even worth thinking about collecting the gas just to react it chemically, because the payoff is literally millions of times lower. > But nuclear fusion does not require such a hard impact. With the ramscoop > beam, we are not trying to make a proton weigh a pound. We need a high > current, true, to assure the density of our cone wall close to the ship. We > don't have to send these particles out so darn fast. We don't want to affect > an unlimited region of space. Our cone boundary is limited by dissipation, > as the final errant particles meet their space resident proton and flare in > fusion. Relative to "cold" space gas, the immediate velocity of the ship > which projects the particles is added to the speed at which they're shot. What makes you think the forward beam can successfully induce fusion at a high rate? It's much more likely that the forward beam will just scatter the gas atoms around. Also, I'm rather doubtful that your conical beam will be able to collect even as much gas as it will take to make the beam in the first place; that combined with the beam producing lots of thrust in the wrong direction makes this whole thing still sound really untenable to me. > > > Producing the cone by sending out light ions forward gives a > decelerating > > > force, but (hopefully) this may be negligible compared to the chemical > > > energy released. > > > > You're trying to reach relativistic speeds with _chemical_ reactions? > > Pardon me, but ha ha ha ha ha ha ha. It's difficult enough, in terms of > > fuel-to-payload ratio, to use fusion to reach even low relativistic > > speeds; with fusion fuel you're looking at very roughly 10^6:1 > > fuel:payload. You're talking about reactions that are several orders of > > magnitude less efficient at mass-energy conversion, which means more > > orders of magnitude increase in the fuel-to-payload ratio. > > Look closer: how much of this fuel am I carrying? None, right? What does > that make the ratio? It would be fine to keep a 1:1, or even a 10:1 ice > ratio aboard, for shielding, but it isn't needed for fuel. Hydrogen can be > harvested any time from the rushing stream about. Run the numbers. It's already doubtful that you can gather enough interstellar gas with a ramscoop to make a fusion-powered starship feasible if you need millions of times as much gas as your starship weighs; if you need trillions of times as much hydrogen for chemical fuel as your starship weighs, and your best estimate of interstellar gas density is only about a hundred times what's likely to exist, you've already lost. From VM Tue Mar 6 14:26:07 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1041" "Tuesday" "6" "March" "2001" "16:01:23" "-0600" "L. Parker" "lparker@cacaphony.net" nil "23" "RE: starship-design: Fusion Cone Scoop" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1041 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f26M6Nt10207 for starship-design-outgoing; Tue, 6 Mar 2001 14:06:23 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f26M6Lp10200 for ; Tue, 6 Mar 2001 14:06:21 -0800 (PST) Received: from broadsword (p463.gnt.com [204.49.91.79]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id QAA00637; Tue, 6 Mar 2001 16:06:14 -0600 Message-ID: <001801c0a689$85553c60$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 In-Reply-To: <15013.19461.548413.939470@tzadkiel.efn.org> Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "'Steve VanDevender'" , "'Starship Design List'" Subject: RE: starship-design: Fusion Cone Scoop Date: Tue, 6 Mar 2001 16:01:23 -0600 I know I am butting into the middle here, so please excuse me if I say something already covered... First, drag on an electromagnetic scoop: Not an issue, since the scoop is _attracting_ the ionized atoms, it is generating a net pull against a (relatively) stationary object. There IS NO drag, you realize acceleration out of the scoop process instead. Second, ionization of the interstellar medium: Requires only lasers, and relatively low powered ones at that. See Forward et. al., too many references to list here. Third, ignition of fusion burn: No outside ignition source required, the magnetic fields generated by the scoop and the velocity of the accelerated ionized atoms create a stellerator type fusion engine (Podovsky? I'm not sure...it was a Russian though.) The only catch is getting the thing up to a velocity where it will work at all, very much like an air breathing ramjet. And yes, the density of the interstellar medium is still an issue. The lower the density, the greater the velocity required for ignition. Lee From VM Wed Mar 7 10:03:19 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1746" "Tuesday" "6" "March" "2001" "23:43:38" "-0800" "Steve VanDevender" "stevev@efn.org" nil "35" "RE: starship-design: Fusion Cone Scoop" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1746 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f277iCq11297 for starship-design-outgoing; Tue, 6 Mar 2001 23:44:12 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f277iB611292 for ; Tue, 6 Mar 2001 23:44:11 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f277i9F17909 for ; Tue, 6 Mar 2001 23:44:09 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f277hwu00405; Tue, 6 Mar 2001 23:43:58 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15013.59050.809411.785915@tzadkiel.efn.org> In-Reply-To: <001801c0a689$85553c60$0100a8c0@broadsword> References: <15013.19461.548413.939470@tzadkiel.efn.org> <001801c0a689$85553c60$0100a8c0@broadsword> X-Mailer: VM 6.91 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: Subject: RE: starship-design: Fusion Cone Scoop Date: Tue, 6 Mar 2001 23:43:38 -0800 L. Parker writes: > First, drag on an electromagnetic scoop: Not an issue, since the scoop is > _attracting_ the ionized atoms, it is generating a net pull against a > (relatively) stationary object. There IS NO drag, you realize acceleration > out of the scoop process instead. > Second, ionization of the interstellar medium: Requires only lasers, and > relatively low powered ones at that. See Forward et. al., too many > references to list here. That depends on how asymmetrical the scoop field is. It doesn't peg my implausibility meter to consider the possibility of having a scoop field that attracts ionized gas in front of it. And yes, lasers are going to be much more effective at ionizing a large quantity of gas than any particle beam would be. > Third, ignition of fusion burn: No outside ignition source required, the > magnetic fields generated by the scoop and the velocity of the accelerated > ionized atoms create a stellerator type fusion engine (Podovsky? I'm not > sure...it was a Russian though.) I'm wondering you couple the ship to the fusion exhaust such that the ship realizes thrust from it. > The only catch is getting the thing up to a velocity where it will work at > all, very much like an air breathing ramjet. And yes, the density of the > interstellar medium is still an issue. The lower the density, the greater > the velocity required for ignition. Presumably if you can get that ramscoop fusion system going you've already figured out how to fuse stationary hydrogen, so just run a more normal fusion reactor off of a booster tank of hydrogen fuel to get up to the speed where you can ignite the ramscoop fusion system. Assuming that's not up into high relativistic speeds, anyway. From VM Wed Mar 7 10:03:19 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2192" "Wednesday" "7" "March" "2001" "00:18:14" "-0800" "Steve VanDevender" "stevev@efn.org" nil "42" "starship-design: spinning up the Moon" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 2192 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f278Ij517524 for starship-design-outgoing; Wed, 7 Mar 2001 00:18:45 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f278Ii617519 for ; Wed, 7 Mar 2001 00:18:44 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f278IhF21929 for ; Wed, 7 Mar 2001 00:18:43 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f278IVD00468; Wed, 7 Mar 2001 00:18:31 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15013.61126.544098.190105@tzadkiel.efn.org> X-Mailer: VM 6.91 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: starship-design: spinning up the Moon Date: Wed, 7 Mar 2001 00:18:14 -0800 I did a little research into what it would really take to spin up the Moon to a higher rotation rate. The angular momentum of a body is in units of kg * m^2 / s, which you can think of as kg (mass) * m (moment arm) * m/s (rotational velocity). The Moon has a mass of some 7.35 * 10^22 kg and a radius of 1740 km. Assuming it's a uniform-density sphere (not quite right, but sufficient for approximation), its angular momentum for a given rotation rate w (in 1/s) will be m * 2/5 r^2 * w. Its rotation rate is about 1 / 2.55 * 10^6 s. The Moon's current angular momentum is therefore about 8.72 * 10^28 kg*m^2/s. Spinning it up to have a rotation rate of 24 hours would increase its angular momentum to 1.03 * 10^30 kg*m^2/s, for a total change in angular momentum of 9.43 * 10^29 kg*m^2/s. So let's suppose, just for the sake of argument, that we have a way to smack comets or asteroids tangentially into the Moon's surface in such a way as to perfectly transfer their linear momentum to the Moon's angular momentum. That would mean a mass M striking at a radius of 1740 km with a velocity of v m/s, transferring a total angular momentum of M * v * 1.74 * 10^6 kg*m^2/s. So to spin up the Moon, we need a quantity of momentum M * v = 5.42 kg*m/s. So you can determine how much mass M would be required for a given impact velocity v, or given mass M what velocity v it would have to be traveling at to achieve the intended angular momentum change. Let's say you can manage to smack those objects into the Moon at 50 km/s (rather untenable, since that velocity's probably much too high to expect that the momentum would be efficently transferred). That means you'd need a mass of comets/asteroids of 1.08 * 10^19 kg, or that you'd need about 1/6780 the mass of the Moon in comets/asteroids impacting at that velocity _and transferring ther momentum entirely_ to get the Moon spun up. With lower impact velocities the mass ratio goes up proportionally; i.e. for impactors moving at 10 km/s you'd need five times as much mass as for impactors moving at 50 km/s. Even 1/10000 the mass of the Moon might not seem like much, but that translates into a pretty huge quantity of comets. From VM Thu Mar 8 10:12:58 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["4795" "Thursday" "8" "March" "2001" "07:57:36" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "77" "Re: starship-design: Fusion Cone Scoop" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 4795 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f28DrIc05710 for starship-design-outgoing; Thu, 8 Mar 2001 05:53:18 -0800 (PST) Received: from mail1.mco.bellsouth.net (mail1.mco.bellsouth.net [205.152.111.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f28DrG605704 for ; Thu, 8 Mar 2001 05:53:16 -0800 (PST) Received: from nless (adsl-21-217-62.msy.bellsouth.net [66.21.217.62]) by mail1.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id IAA18280 for ; Thu, 8 Mar 2001 08:53:15 -0500 (EST) Message-ID: <000f01c0a7d7$bf1c8b20$0a0a0a0a@nless> References: <000d01c0a625$8e2a1fe0$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Fusion Cone Scoop Date: Thu, 8 Mar 2001 07:57:36 -0600 In-System Scoops? Chemical boost, using the local gas medium, does not have to show it can achieve lightspeed, to make it worth while. It only has to show it can produce a 1 g sustained acceleration, in some range of velocities, to fit with my schedule of preferred star flight techniques, to make it eligible as a phase or stage in the propulsion of the starship. The spin off of this, is possibly a very good way to build interplanetary vehicles, for the solar wind is probably much denser than interstellar winds. Before we routinely use particle beams in our system, however, we must firmly establish the principle that you have to be careful where you aim that thing. You might put somebody's eye out. Though we might normally think a ram scoop would be useless in the solar system, that it scarcely has room to get up to speed, reflection shows that Hohmann least-energy transfer orbits, which take months, years or decades to get from planet "Hither" to planet "Yon", are not very appealing as a way to travel. If we can show the principle, that the interplanetary gas can also be concentrated to the point at which it will yield its chemical energy of recombination, to produce sustained thrust, this will lubricate the Solar System economy enough that starship building becomes a feasible project. Ease of fast transportation around this system, will increase available resources by many orders of magnitude, making us a much wealthier species. So can the ram scoop be useful in the system? The gas is roughly the same stuff. Since the solar wind is denser than the interstellar medium, the principle of inward compression by circumferential fusion, should apply to it. A cone shaped particle beam traversing through it should produce the desired concentration, assuming the beam does indeed ignite diffuse fusion reactions of the order needed for bulk movement of the gas and plasma. Since we know that particle beams in the lab do give fusion, at precisely predictable energies, we can directly extrapolate these experimental results to free space conditions. It is calculable how intense a cone beam would need to be, to produce fusion in the medium which will gather in our gas. (Speeds needed are in KeV's, not MeV's. Electrons go that fast in your monitor's picture tube.) So the ram scoop can be run in simulation with current software. Even I can do this, if I can get my mind wrapped around learning it. Somebody else can if I can't, for we are dealing with known phenomona, according to firmly established physical laws. The fusion scoop, as a virtual machine model, can be realized immediately, so if it works in the simulation, a test prototype can be built and flown. This becomes science, for it is subject to Karl Popper's falsifiability criterion for experimental science. It's a long way out to the Kuiper Belt. Beyond that, it's a long, long, way to the Oort Cloud, and lots of room above the ecliptic to shake out our space legs. There is good new science to be learned, up those gravitational hills, and there are some very collectible comets and asteroids, which might be worth a pretty penny back home. A one-gravity acceleration is too much for use within the system, we can settle for less. But sustained acceleration, and sustained deceleration, are concepts which will cause a sea change in our ideas of space travel. These are only practicable if locally resident energy and mass are harvested for a reaction engine, rather than the ship carrying its own fuel. That space gas is explosive on compression, has evidently been overlooked before. The hottest rocket engine we have now, gives but a small fraction of the energy available, by simply squeezing the gas of space. The energy we must use to form our collection beam is in the nature of a catalyst. The beam is all consumed in fusion production. I expect practically none of its constituent particles to be slowed in elastic collisions and thermalized. The total fusion production will release excess energy, in an amount to vastly outweigh the beam projection energy. The potential chemical energy, in the cloud gathered for us by our fusion ram, is our bonus. It is not directly related to the energy expended to gather it, for the same ram scoop energy could be used to compress an inert gas. Instead, we are collecting atomic hydrogen, the most powerful rocket fuel which may be. There is only a gross and indirect proportionality of the chemical energy which moves the ship, to the electrical energy first spent to generate the scoop. The fusion itself dwarfs our beam energy, giving us the chemical energy, an amount much greater than either our beam or its fusion, for free. Nature didn't have to fill space with rocket fuel. Since She did, we would do well to use it. Johnny Thunderbird From VM Thu Mar 8 10:12:58 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["822" "Thursday" "8" "March" "2001" "09:51:40" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "21" "Re: starship-design: spinning up the Moon" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 822 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f28H0gb12071 for starship-design-outgoing; Thu, 8 Mar 2001 09:00:42 -0800 (PST) Received: from mail0.mco.bellsouth.net (mail0.mco.bellsouth.net [205.152.111.12]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f28H0eV11938 for ; Thu, 8 Mar 2001 09:00:40 -0800 (PST) Received: from nless (adsl-21-217-62.msy.bellsouth.net [66.21.217.62]) by mail0.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id KAA13115 for ; Thu, 8 Mar 2001 10:47:23 -0500 (EST) Message-ID: <002101c0a7e7$b060ed00$0a0a0a0a@nless> References: <15013.61126.544098.190105@tzadkiel.efn.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: Subject: Re: starship-design: spinning up the Moon Date: Thu, 8 Mar 2001 09:51:40 -0600 From: Steve VanDevender > at 50 km/s you'd need a mass of comets/asteroids of 1.08 * 10^19 kg > about 1/6780 the mass of the Moon > to get the Moon spun up. > > that translates into a pretty huge > quantity of comets. Thanks a lot for this hard data, Steve. And the work you did, to bring it to us. We need more of this approach in here, facts with numbers. I admit 10^19 kg is pretty heavy, if your impactors are ~10^7 or 10^8 kg each. This was a low probability anyway, for if anyone were settled on the Moon you could never land a single rock. Rethinking time. By the way, my friend informed me Frederik Pohl in "Mining the Oort" (Del Rey, 1992; ISBN 0-345-37199-2) anticipated the use of volatile ices to build the atmosphere of Mars. His Mars settlers just dodged the incoming comet fragments! Johnny Thunderbird From VM Thu Mar 8 12:52:14 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["997" "Thursday" "8" "March" "2001" "12:45:29" "-0800" "Steve VanDevender" "stevev@efn.org" nil "19" "Re: starship-design: Fusion Cone Scoop" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 997 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f28KjnC22779 for starship-design-outgoing; Thu, 8 Mar 2001 12:45:49 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f28KjmV22767 for ; Thu, 8 Mar 2001 12:45:48 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f28KjkF24853 for ; Thu, 8 Mar 2001 12:45:47 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f28KjWs04977; Thu, 8 Mar 2001 12:45:32 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15015.61289.282340.290163@tzadkiel.efn.org> In-Reply-To: <000f01c0a7d7$bf1c8b20$0a0a0a0a@nless> References: <000d01c0a625$8e2a1fe0$0a0a0a0a@nless> <000f01c0a7d7$bf1c8b20$0a0a0a0a@nless> X-Mailer: VM 6.91 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Fusion Cone Scoop Date: Thu, 8 Mar 2001 12:45:29 -0800 bugzapper writes: > In-System Scoops? Ramscoops are pretty much pointless for in-system use. A few tons of hydrogen fuel and a fusion reactor would be capable of propelling a large ship on continuous-acceleration trajectories within the solar system. You probably couldn't even get the ship up to a speed where the ramscoop would be effective within the solar system, and you'd have to carry all the extra weight of the ramscoop equipment. You probably also wouldn't want to sweep a ramscoop field through a planetary atmosphere accidentally, and a usable ramscoop field would be the size of a planet. There are already people doing research into spacecraft that we could build with current technology that would use electromagnetic interaction with the solar wind to propel spacecraft. That would pretty much only be useful for propulsion away from the Sun, but it would get spacecraft up into the hundreds of km/s, which would be very useful for sending probes to the outer solar system. From VM Thu Mar 8 17:26:55 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["6571" "Thursday" "8" "March" "2001" "20:11:31" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "142" "starship-design: Fwd: Marshal wants a HTOL SSTO??" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 6571 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f291BwU28340 for starship-design-outgoing; Thu, 8 Mar 2001 17:11:58 -0800 (PST) Received: from imo-m04.mx.aol.com (imo-m04.mx.aol.com [64.12.136.7]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f291BuV28293 for ; Thu, 8 Mar 2001 17:11:56 -0800 (PST) Received: from KellySt@aol.com by imo-m04.mx.aol.com (mail_out_v29.5.) id n.17.12a161f2 (4219); Thu, 8 Mar 2001 20:11:31 -0500 (EST) Message-ID: <17.12a161f2.27d987c3@aol.com> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="part1_17.12a161f2.27d987c3_boundary" X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: DTaylor648@aol.com, JohnFrance@aol.com, moschleg@erols.com, SFnoirSD@aol.com, starship-design@lists.uoregon.edu Subject: starship-design: Fwd: Marshal wants a HTOL SSTO?? Date: Thu, 8 Mar 2001 20:11:31 EST --part1_17.12a161f2.27d987c3_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 3/8/01 2:29:53 PM, kgstarks@collins.rockwell.com writes: >Development Of A Horizontal Take-Off & Landing Rocket-Based Combined Cycle >(Rbcc) Single Stage To Orbit Vehicle Concept > >NOTICE TYPE: Solicitation > >NOTICE DATED: 030601 > >OFFICE ADDRESS: NASA/George C. Marshall Space Flight Center, Procurement >Office, Marshall Space Flight Center, >AL 35812 > >ZIP CODE: 35812 > >SOLICITATION NO.: SOL 8-1-1-T3-D3033 > >RESPONSE DEADLINE: DUE 032101 > >CONTACT: POC Teresa A. Foley, Contracting Officer, Phone (256) 544- 0335, >Fax (256) 544-2812, Email >teresa.foley@msfc.nasa.gov -- George E. Pendley, Contracting Officer, Phone >(256) 544-2949, Fax (256) 544- 2812, >Email george.pendley@msfc.nasa.gov > >NOTICE TEXT: NASA/MSFC plans to issue a Request for Quotation (RFQ) for >the Development of a Horizontal Take-Off and Landing (HTHL) >Rocket-Based Combined Cycle (RBCC) Single Stage-to-Orbit (SSTO) Vehicle >Concept. This procurement is being conducted under the Simplified >Acquisition Procedures (SAP). NASA/MSFC intends to purchase the items from >Space Works Engineering, Inc., 170 Park Creek Drive, Alpharetta, GA. >This sole source is recommended pursuant to FAR 13.106-1(b). The contractor >shall provide multi-disciplinary technical services in support of an HTHL >RBCC SSTO in-house conceptual design. Required disciplinary support includes >trajectory, aerodynamic, propulsion, and aerothermal analysis, as well >as, >thermal protection system sizing, operations analysis and economic analysis. >The Government does not intend to acquire a commercial item using FAR >Part >12. See Note 26. Interested organizations may submit their capabilities >and qualifications to perform the effort in writing to the identified point >of > contact not >later than 4:30 p.m. local time on March 21, 2001. Such capabilities/qualifications >will be evaluated solely for the purpose of determining whether or > not to >conduct this procurement on a competitive basis. A determination by the >Government not to compete this proposed effort on a full and open competition >basis, based upon responses to this notice is solely within the discretion >of the government. Oral communications are not acceptable in response to >this notice. >All responsible sources may submit an offer which shall be considered by >the agency. An Ombudsman has been appointed. See NASA Specific Note "B". >Any referenced notes can be viewed at the following URL: http://genesis.gsfc.nasa.gov/ >nasanote.html > >INTERNET ADDRESS (URL): http://nais.msfc.nasa.gov/cgi- bin/EPS/ bizops.cgi?gr=D&pin=62#8-1-1-T3-D3033 > >EMAIL ADDRESS: teresa.foley@msfc.nasa.gov > >-- Teresa A. Foley > >RECEIVED: (D-065 SN50F4A1) --part1_17.12a161f2.27d987c3_boundary Content-Type: message/rfc822 Content-Disposition: inline Return-Path: Received: from rly-yd05.mx.aol.com (rly-yd05.mail.aol.com [172.18.150.5]) by air-yd01.mail.aol.com (v77_r1.21) with ESMTP; Thu, 08 Mar 2001 15:29:53 -0500 Received: from fw01.collins.rockwell.com (gatekeeper.collins.rockwell.com [205.175.225.1]) by rly-yd05.mx.aol.com (v77_r1.21) with ESMTP; Thu, 08 Mar 2001 15:29:38 -0500 Received: by fw01.collins.rockwell.com; id OAA22238; Thu, 8 Mar 2001 14:29:17 -0600 (CST) From: Received: from nodnsquery(131.198.213.32) by fw01.collins.rockwell.com via smap (V5.5) id xma021937; Thu, 8 Mar 01 14:28:12 -0600 Subject: Marshal wants a HTOL SSTO?? To: kellyst@aol.com Date: Thu, 8 Mar 2001 14:21:49 -0600 Message-ID: X-MIMETrack: Serialize by Router on CollinsCRSMTP01/CedarRapids/Collins/Rockwell(Release 5.0.6 |December 14, 2000) at 03/08/2001 02:28:15 PM MIME-Version: 1.0 Content-type: text/plain; charset=us-ascii X-Mailer: Unknown (No Version) Development Of A Horizontal Take-Off & Landing Rocket-Based Combined Cycle (Rbcc) Single Stage To Orbit Vehicle Concept NOTICE TYPE: Solicitation NOTICE DATED: 030601 OFFICE ADDRESS: NASA/George C. Marshall Space Flight Center, Procurement Office, Marshall Space Flight Center, AL 35812 ZIP CODE: 35812 SOLICITATION NO.: SOL 8-1-1-T3-D3033 RESPONSE DEADLINE: DUE 032101 CONTACT: POC Teresa A. Foley, Contracting Officer, Phone (256) 544- 0335, Fax (256) 544-2812, Email teresa.foley@msfc.nasa.gov -- George E. Pendley, Contracting Officer, Phone (256) 544-2949, Fax (256) 544- 2812, Email george.pendley@msfc.nasa.gov NOTICE TEXT: NASA/MSFC plans to issue a Request for Quotation (RFQ) for the Development of a Horizontal Take-Off and Landing (HTHL) Rocket-Based Combined Cycle (RBCC) Single Stage-to-Orbit (SSTO) Vehicle Concept. This procurement is being conducted under the Simplified Acquisition Procedures (SAP). NASA/MSFC intends to purchase the items from Space Works Engineering, Inc., 170 Park Creek Drive, Alpharetta, GA. This sole source is recommended pursuant to FAR 13.106-1(b). The contractor shall provide multi-disciplinary technical services in support of an HTHL RBCC SSTO in-house conceptual design. Required disciplinary support includes trajectory, aerodynamic, propulsion, and aerothermal analysis, as well as, thermal protection system sizing, operations analysis and economic analysis. The Government does not intend to acquire a commercial item using FAR Part 12. See Note 26. Interested organizations may submit their capabilities and qualifications to perform the effort in writing to the identified point of contact not later than 4:30 p.m. local time on March 21, 2001. Such capabilities/qualifications will be evaluated solely for the purpose of determining whether or not to conduct this procurement on a competitive basis. A determination by the Government not to compete this proposed effort on a full and open competition basis, based upon responses to this notice is solely within the discretion of the government. Oral communications are not acceptable in response to this notice. All responsible sources may submit an offer which shall be considered by the agency. An Ombudsman has been appointed. See NASA Specific Note "B". Any referenced notes can be viewed at the following URL: http://genesis.gsfc.nasa.gov/ nasanote.html INTERNET ADDRESS (URL): http://nais.msfc.nasa.gov/cgi- bin/EPS/ bizops.cgi?gr=D&pin=62#8-1-1-T3-D3033 EMAIL ADDRESS: teresa.foley@msfc.nasa.gov -- Teresa A. Foley RECEIVED: (D-065 SN50F4A1) --part1_17.12a161f2.27d987c3_boundary-- From VM Mon Mar 12 13:21:16 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["710" "Monday" "12" "March" "2001" "13:15:13" "-0800" "Steve VanDevender" "stevev@darkwing.uoregon.edu" nil "16" "starship-design: Rex Finke's \"Starflight Mechanics Notes\"" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 710 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2CLFE816388 for starship-design-outgoing; Mon, 12 Mar 2001 13:15:14 -0800 (PST) Received: (from stevev@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2CLFDr16375; Mon, 12 Mar 2001 13:15:13 -0800 (PST) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15021.15457.744604.806407@darkwing.uoregon.edu> X-Mailer: VM 6.91 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: starship-design: Rex Finke's "Starflight Mechanics Notes" Date: Mon, 12 Mar 2001 13:15:13 -0800 List member Rex Finke has written a paper "Starflight Mechanics Notes" which collects and summarizes many of the major physics and engineering topics discussed earlier in starship-design. As the paper is a bit too large to post to the list directly, I'm offering it as part of the starship-design archive pages. He has provided both Microsoft Word and Postscript versions of the document. You can get the paper from: http://darkwing.uoregon.edu/~stevev/sd-archive/starflight.doc (Microsoft Word) http://darkwing.uoregon.edu/~stevev/sd-archive/starflight.ps (Postscript) I've also included links to the paper from the main starship-design archive web page, http://darkwing.uoregon.edu/~stevev/sd-archive/ From VM Mon Mar 12 18:12:56 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["3500" "Monday" "12" "March" "2001" "20:10:30" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "66" "Re: starship-design: Fusion Cone Scoop" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 3500 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2D26CO19279 for starship-design-outgoing; Mon, 12 Mar 2001 18:06:12 -0800 (PST) Received: from mail0.mco.bellsouth.net (mail0.mco.bellsouth.net [205.152.111.12]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2D26AV19272 for ; Mon, 12 Mar 2001 18:06:10 -0800 (PST) Received: from nless (adsl-21-218-51.msy.bellsouth.net [66.21.218.51]) by mail0.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id VAA01682 for ; Mon, 12 Mar 2001 21:06:07 -0500 (EST) Message-ID: <000b01c0ab62$ccc9dd20$0a0a0a0a@nless> References: <001801c0a689$85553c60$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "'Starship Design List'" Subject: Re: starship-design: Fusion Cone Scoop Date: Mon, 12 Mar 2001 20:10:30 -0600 Lee sure got my attention with: > First, drag on an electromagnetic scoop: Not an issue, since the scoop is > _attracting_ the ionized atoms, it is generating a net pull against a > (relatively) stationary object. There IS NO drag, you realize acceleration > out of the scoop process instead. Way cool! This meditation calls for some thought. Steve slowed my enthusiasm for an EM scoop with his comments on drag, which I'd never even considered. Your contribution does seem sensible, as did his at first, but we need details to resolve the matter. Further comments? Anybody? > Second, ionization of the interstellar medium: Requires only lasers, and > relatively low powered ones at that. See Forward et. al., too many > references to list here. Listen: if you ionize only the outer sheath of the volume of gas you scoop in, it may serve as an envelope to compress its enclosed column of neutral gas. This gives an electromagnetic "handle" by which you can manipulate non-ionized gas in bulk, using the ionized plasma layer to transmit the pressure to it. This way you need less energy expended in ionization at first. Lasers couple energy well to the task of ionizing gas, particularly at short wavelengths, in the UV. Free electron lasers are very promising; also frequency multiplying substances may be used. Urea is a frequency tripler. Since I figured a week or two ago, that free gas in space has enormous potential chemical energy, I have looked for a way to make use of this resource. That's why I'm interested in a method of scoop compression which doesn't require extensive ionization of the bulk of the gas. I feel that a real ship design will use a mixture of techniques, rather than one all-encompassing approach to traverse space. To reject anything out of hand, such as chemical recombination, which produces a net gain of energy, is an error. > Third, ignition of fusion burn: No outside ignition source required, the > magnetic fields generated by the scoop and the velocity of the accelerated > ionized atoms create a stellerator type fusion engine That's also a very appealing observation. I think that another stage of magnetic squeezing, after the ram scoop field, might be called for to induce fusion. This makes the plasma more controllable. Also, it gives an opportunity for a spectroscopy field prior to the fusion region. Pulling heavy elements out of thin "air", as it were, allows the ship to actually gain useful matter in transit. Building things en route could be very handy, especially if the ship didn't boost all the mass used for the new construction. > The only catch is getting the thing up to a velocity where it will work at > all, very much like an air breathing ramjet. And yes, the density of the > interstellar medium is still an issue. The lower the density, the greater > the velocity required for ignition. > > Lee Your picture of a magnetic scoop with fusion burn is elegant. We ought to get beyond fussing with theories, and progress into physical modeling. Looking into simulation software on the fuzzy fringes of physics, I have been able to find real treasures for free, at the big accelerator sites. Now I'm dreaming of proving out some of my wild proposals, and yours, and others. Lots of work, and it won't happen tomorrow. Steve brought up Rex Finke's review, of this list's earlier results, at just the right time. Those Fortran programs look good to build on, or to convert and build with, and we're on our way. Johnny Thunderbird From VM Mon Mar 12 18:25:57 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["711" "Monday" "12" "March" "2001" "18:20:46" "-0800" "Steve VanDevender" "stevev@efn.org" nil "13" "Re: starship-design: Fusion Cone Scoop" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 711 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2D2LCv24338 for starship-design-outgoing; Mon, 12 Mar 2001 18:21:12 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2D2LBV24332 for ; Mon, 12 Mar 2001 18:21:11 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f2D2L9114412 for ; Mon, 12 Mar 2001 18:21:10 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f2D2Kl122858; Mon, 12 Mar 2001 18:20:47 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15021.33790.86789.82866@tzadkiel.efn.org> In-Reply-To: <000b01c0ab62$ccc9dd20$0a0a0a0a@nless> References: <001801c0a689$85553c60$0100a8c0@broadsword> <000b01c0ab62$ccc9dd20$0a0a0a0a@nless> X-Mailer: VM 6.92 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "'Starship Design List'" Subject: Re: starship-design: Fusion Cone Scoop Date: Mon, 12 Mar 2001 18:20:46 -0800 bugzapper writes: > Since I figured a week or two ago, that free gas in space has enormous > potential chemical energy, I have looked for a way to make use of this > resource. You may think it's enormous, but it's probably not enormous in comparison to the amount of energy needed to run a ramscoop starship and boost the ship to relativistic speeds. As I said before, even with the optimistic estimates of interstellar gas density you believe in, it's questionable whether a ramscoop can really collect enough fuel to work even by fusion. If you cut the amount of energy you get by several orders of magnitude by using it for chemical energy rather than fusion, then it makes the numbers far, far worse. From VM Tue Mar 13 10:21:25 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2734" "Monday" "12" "March" "2001" "23:32:18" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "98" "starship-design: Fwd: New in Archive" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 2734 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2D4WWO04315 for starship-design-outgoing; Mon, 12 Mar 2001 20:32:32 -0800 (PST) Received: from imo-r15.mx.aol.com (imo-r15.mx.aol.com [152.163.225.69]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2D4WVV04307 for ; Mon, 12 Mar 2001 20:32:31 -0800 (PST) Received: from KellySt@aol.com by imo-r15.mx.aol.com (mail_out_v29.5.) id z.23.8a3eb7e (4215) for ; Mon, 12 Mar 2001 23:32:18 -0500 (EST) Message-ID: <23.8a3eb7e.27defcd2@aol.com> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="part1_23.8a3eb7e.27defcd2_boundary" X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: starship-design: Fwd: New in Archive Date: Mon, 12 Mar 2001 23:32:18 EST --part1_23.8a3eb7e.27defcd2_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 3/12/01 8:53:49 AM, kgstarks@collins.rockwell.com writes: >Subject: Fwd: New in Archive > > > >In a message dated 2/19/01 3:53:51 PM, pan@darkhavn.demon.co.uk writes: > >>New in archive: >> >>The Prospects for Passenger Space Travel >>(Patrick Collins, February 2001) >> > >http://www.spacefuture.com/archive/the_prospects_for_passenger_space_travel.s html > > >> >>For those who have been waiting for it, this is the transcript >>of Dr. Collins' speech at the recent AST conference in Washington >>DC. Enjoy :-) --part1_23.8a3eb7e.27defcd2_boundary Content-Type: message/rfc822 Content-Disposition: inline Return-Path: Received: from rly-xd01.mx.aol.com (rly-xd01.mail.aol.com [172.20.105.166]) by air-xd01.mail.aol.com (v77_r1.21) with ESMTP; Mon, 12 Mar 2001 09:53:48 -0500 Received: from fw01.collins.rockwell.com (gatekeeper.collins.rockwell.com [205.175.225.1]) by rly-xd01.mx.aol.com (v77_r1.21) with ESMTP; Mon, 12 Mar 2001 09:53:32 -0500 Received: by fw01.collins.rockwell.com; id IAA00372; Mon, 12 Mar 2001 08:53:31 -0600 (CST) From: Received: from nodnsquery(131.198.213.32) by fw01.collins.rockwell.com via smap (V5.5) id xma029593; Mon, 12 Mar 01 08:52:35 -0600 Subject: Re: Fwd: New in Archive To: KellySt@aol.com Date: Mon, 12 Mar 2001 08:46:08 -0600 Message-ID: X-MIMETrack: Serialize by Router on CollinsCRSMTP01/CedarRapids/Collins/Rockwell(Release 5.0.6 |December 14, 2000) at 03/12/2001 08:52:35 AM MIME-Version: 1.0 Content-type: text/plain; charset=us-ascii X-Mailer: Unknown (No Version) KellySt@aol.com on 03/08/2001 07:42:56 PM To: kgstarks@crnotes.collins.rockwell.com cc: Subject: Fwd: New in Archive In a message dated 2/19/01 3:53:51 PM, pan@darkhavn.demon.co.uk writes: >New in archive: > >The Prospects for Passenger Space Travel >(Patrick Collins, February 2001) > http://www.spacefuture.com/archive/the_prospects_for_passenger_space_travel.shtml > >For those who have been waiting for it, this is the transcript >of Dr. Collins' speech at the recent AST conference in Washington >DC. Enjoy :-) > >-- >=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= >Peter Wainwright Cybrid Technology Ltd. Peter.Wainwright@cybrid.net >=[ http://www.spacefuture.com ]=[ Peter.Wainwright@spacefuture.com ]= > >-- >Space Future | To unsubscribe send email with the subject "unsubscribe" >www.spacefuture.com | to "sf-announce-request@spacefuture.com". > --part1_23.8a3eb7e.27defcd2_boundary-- From VM Tue Mar 13 10:21:25 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["4735" "Tuesday" "13" "March" "2001" "01:35:29" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "80" "Re: starship-design: Fusion Cone Scoop" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 4735 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2D7V7i24531 for starship-design-outgoing; Mon, 12 Mar 2001 23:31:07 -0800 (PST) Received: from mail2.mco.bellsouth.net (mail2.mco.bellsouth.net [205.152.111.14]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2D7V6V24525 for ; Mon, 12 Mar 2001 23:31:06 -0800 (PST) Received: from nless (adsl-21-218-51.msy.bellsouth.net [66.21.218.51]) by mail2.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id CAA00281 for ; Tue, 13 Mar 2001 02:21:27 -0500 (EST) Message-ID: <002d01c0ab90$307099e0$0a0a0a0a@nless> References: <001801c0a689$85553c60$0100a8c0@broadsword><000b01c0ab62$ccc9dd20$0a0a0a0a@nless> <15021.33790.86789.82866@tzadkiel.efn.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "'Starship Design List'" Subject: Re: starship-design: Fusion Cone Scoop Date: Tue, 13 Mar 2001 01:35:29 -0600 > it's questionable whether a ramscoop can really collect enough fuel to > work You just don't like ramscoops, do you Steve? The fact is, a ramscoop does take energy to operate. It has to be a very large construct, far too large to be feasibly constructed wirh matter. It must be built of less substantial fabric, fields or shock waves or other dynamic extensions of the ship, and these require a continuous energy expenditure to maintain. A magnetic funnel doesn't necessarily need sustained energy input to maintain its structure, but because it only works for plasma, and the medium is mostly atomic, ionization energy must be added. Also, if the magnetic current loop solenoid forming the scoop field is physically detatched from the ship structure, because of being big, further energy must be expended to hold it in place, in front of (perceptually "above") the ship. But the magnitude of these energy debits is not determined yet. I suggested a different type of ramscoop, to gather gas which was not ionized, and also to gather plasma, indiscriminately. This would use a hollow bow shock, formed of a continuous conical explosion front from thermonuclear reactions. Fusion would be engendered by a fast particle beam of cone shape. Once again, the energy cost cannot even be estimated until the system is further specified. But it should be noted, that the fusion energy which actually produces the bulk movement of the gas does not come from the ship's energy reserves, but from the nuclei of the space gas. It is disproportionate to the amount of energy used to project the particle beam. With either version of the ram scoop, the energy spent to gather in gas is proportional to the volume of space swept by the scoop. The lower the density of the space gas encountered, the larger the scooped region must be, so the scoop becomes energetically costlier at lower gas densities. This is a scaling problem with the electromagnetic scoop, which deals with an inverse square law on the propagation of its effectiveness. The fusion scoop has no inherent size limits. Yet we can't firm up any specifications for ram scoop designs, until we have a good idea how thick the gas is in local interstellar space. A few years ago, people thought it must be a bit less than the gas in our system, which has 2 or 3 particles per cc when the sun's quiet. More recently, evidence has been found that we may have just entered a gas cloud, which could make the gas density in local interstellar space actually higher than it is in our solar system. I believe next year, Voyager 1 will cross the heliopause at 100 AU, with Voyager 2 following the next year, so we can find out then. Ram scoop proposals are meant to get energy and reaction mass from the ambient medium. They are machines which will work, if there is enough fuel for them to collect, otherwise not. I think the particle beam type scoop may have a better shot at success, for it can be made arbitrarily large. Without hardware changes, you can fire a more narrow cone of particles a greater distance ahead of the ship, as speed increases. A magnet, which is only effective to a fixed distance, has less time to move material at high velocity of traverse. I can understand your reservations about the concept of remotely induced fusion. It takes a high energy beam, so you want me to prove it will pay off the inertial costs, and the sheer energy costs, of producing that beam. I found some high energy physics programs which might help me do that.While I'm working on that, here's another type of scoop for you to hate. It has a similar approach, of conical excitation remotely producing a centralizing compression. Instead of using local fusion to power the compression, it uses local chemical recombination for the purpose. Thermal excitation of the gas medium, produced by a cone of laser illumination, gives a shock front of increased pressure which travels at the ship's speed. Local atoms recombine chemically, as they pile up against that shock front. That traveling explosion gives leverage to the laser's thermal excitation, resulting in a compressive force much greater than that exerted by the laser itself. Though this seems similar in concept to the fusion cone, it's actually much more complex than the other, and will be lots harder to demonstrate. It illustrates using the heating laser for a triggering energy input, like the particle beam which incites fusion in this thread, to release locally resident potential energy from afar. In both cases, the triggering energy is considerable, but is far less than is needed to do the actual work. Your doubts are your own, and certainly they are sensible, but some think scoops may work. Johnny Thunderbird From VM Wed Mar 14 10:09:06 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["8684" "Wednesday" "14" "March" "2001" "00:22:53" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "219" "Fwd: starship-design: Rex Finke's \"Starflight Mechanics Notes\"" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 8684 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2E5NEv26049 for starship-design-outgoing; Tue, 13 Mar 2001 21:23:14 -0800 (PST) Received: from imo-r17.mx.aol.com (imo-r17.mx.aol.com [152.163.225.71]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2E5N8f25995 for ; Tue, 13 Mar 2001 21:23:08 -0800 (PST) Received: from KellySt@aol.com by imo-r17.mx.aol.com (mail_out_v29.5.) id z.4f.8b44028 (18412); Wed, 14 Mar 2001 00:22:53 -0500 (EST) Message-ID: <4f.8b44028.27e05a2d@aol.com> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="part1_4f.8b44028.27e05a2d_boundary" X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu, DotarSojat@aol.com Subject: Fwd: starship-design: Rex Finke's "Starflight Mechanics Notes" Date: Wed, 14 Mar 2001 00:22:53 EST --part1_4f.8b44028.27e05a2d_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 3/13/01 9:50:52 AM, kgstarks@collins.rockwell.com writes: > >Rex, >Just read your LIT starflight paper. Thanks for collecting it together. > >I noticed you sometimes forgot to include units. For example in the MeV >to >speed table you didn't list the units for the resulting speed, nor in all >the definitions of the letters in the equations. (I caught Tim doing that >a couple years ago and he got embarased since his instructors had just >chewed him out for that. ;) ) This significantly limited the number >of >readers who can make use of - or understand - the information. > >I'm not sure why you didn't include reaction rate numbers for all the >fusion reactions on page 14? > >You might want to include full names in quotes? > >Quotes came with " >" at the start of each line; but since you didn't add >hard returns when you added them to the paper, they now sometimes float >in >the sentences. > >I'ld argue with some of your implications that there's a physics limit >to >the project. A nasty engineering to cost limit, yes; but that would >require a very differnt set of solutions. For example my fuel sail concept >(which you didn't mention) with a assumption of greatly reduced automated >systems costs. Or refueling at the target system to eliminate the need >to >carry round trip fuel. Or using a lithium base fusion fuel to eliminate >the need for a tank. Or suplying power/fuel in flight from earth to >eliminate having to carry it. > > >I have a serious problem figuring out the beam power to thrust >relationships for something like a microwave sail system. Even more >problems understanding how the beamed energy can be consentrated into a >conversion system for retro thrust, and get more retrothrust - then forward >thrust from the sail? A critical point since it seems counter-intuative. >(Oh, did anyone consider converting the microwaves to electricity in the >sail [rectena sail?] rather then reflecting and concentrating it? Does >this help?) > > >You might want to look up conversino numbers for free-electron and LED >lasers. I beleave their conversion efficencies are higher. Not sure >though. > > > >In general though a great summary. If I still had access to the web site >I'ld convert it to HTML and link it it. > >Kelly --part1_4f.8b44028.27e05a2d_boundary Content-Type: message/rfc822 Content-Disposition: inline Return-Path: Received: from rly-yh02.mx.aol.com (rly-yh02.mail.aol.com [172.18.147.34]) by air-yh03.mail.aol.com (v77_r1.21) with ESMTP; Tue, 13 Mar 2001 10:50:52 -0500 Received: from fw01.collins.rockwell.com (gatekeeper.collins.rockwell.com [205.175.225.1]) by rly-yh02.mx.aol.com (v77_r1.21) with ESMTP; Tue, 13 Mar 2001 10:50:20 -0500 Received: by fw01.collins.rockwell.com; id JAA28502; Tue, 13 Mar 2001 09:50:10 -0600 (CST) From: Received: from nodnsquery(131.198.213.32) by fw01.collins.rockwell.com via smap (V5.5) id xmaa27462; Tue, 13 Mar 01 09:48:24 -0600 Subject: Re: Fwd: starship-design: Rex Finke's "Starflight Mechanics Notes" To: KellySt@aol.com Date: Tue, 13 Mar 2001 09:41:55 -0600 Message-ID: X-MIMETrack: Serialize by Router on CollinsCRSMTP01/CedarRapids/Collins/Rockwell(Release 5.0.6 |December 14, 2000) at 03/13/2001 09:48:24 AM MIME-Version: 1.0 Content-type: text/plain; charset=us-ascii X-Mailer: Unknown (No Version) Rex, Just read your LIT starflight paper. Thanks for collecting it together. I noticed you sometimes forgot to include units. For example in the MeV to speed table you didn't list the units for the resulting speed, nor in all the definitions of the letters in the equations. (I caught Tim doing that a couple years ago and he got embarased since his instructors had just chewed him out for that. ;) ) This significantly limited the number of readers who can make use of - or understand - the information. I'm not sure why you didn't include reaction rate numbers for all the fusion reactions on page 14? You might want to include full names in quotes? Quotes came with " >" at the start of each line; but since you didn't add hard returns when you added them to the paper, they now sometimes float in the sentences. I'ld argue with some of your implications that there's a physics limit to the project. A nasty engineering to cost limit, yes; but that would require a very differnt set of solutions. For example my fuel sail concept (which you didn't mention) with a assumption of greatly reduced automated systems costs. Or refueling at the target system to eliminate the need to carry round trip fuel. Or using a lithium base fusion fuel to eliminate the need for a tank. Or suplying power/fuel in flight from earth to eliminate having to carry it. I have a serious problem figuring out the beam power to thrust relationships for something like a microwave sail system. Even more problems understanding how the beamed energy can be consentrated into a conversion system for retro thrust, and get more retrothrust - then forward thrust from the sail? A critical point since it seems counter-intuative. (Oh, did anyone consider converting the microwaves to electricity in the sail [rectena sail?] rather then reflecting and concentrating it? Does this help?) You might want to look up conversino numbers for free-electron and LED lasers. I beleave their conversion efficencies are higher. Not sure though. In general though a great summary. If I still had access to the web site I'ld convert it to HTML and link it it. Kelly KellySt@aol.com on 03/12/2001 10:32:25 PM To: kgstarks@crnotes.collins.rockwell.com cc: Subject: Fwd: starship-design: Rex Finke's "Starflight Mechanics Notes" In a message dated 3/12/01 3:18:53 PM, stevev@darkwing.uoregon.edu writes: >List member Rex Finke has written a paper "Starflight Mechanics Notes" >which collects and summarizes many of the major physics and engineering >topics discussed earlier in starship-design. As the paper is a bit too >large to post to the list directly, I'm offering it as part of the >starship-design archive pages. He has provided both Microsoft Word and >Postscript versions of the document. > >You can get the paper from: > >http://darkwing.uoregon.edu/~stevev/sd-archive/starflight.doc (Microsoft >Word) >http://darkwing.uoregon.edu/~stevev/sd-archive/starflight.ps (Postscript) > >I've also included links to the paper from the main starship-design >archive web page, > >http://darkwing.uoregon.edu/~stevev/sd-archive/ Content-Transfer-Encoding: 7bit Return-Path: Received: from rly-xd01.mx.aol.com (rly-xd01.mail.aol.com [172.20.105.166]) by air-xd03.mail.aol.com (v77_r1.21) with ESMTP; Mon, 12 Mar 2001 16:18:53 -0500 Received: from darkwing.uoregon.edu (darkwing.uoregon.edu [128.223.142.13]) by rly-xd01.mx.aol.com (v77_r1.21) with ESMTP; Mon, 12 Mar 2001 16:18:18 1900 Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2CLFE816388 for starship-design-outgoing; Mon, 12 Mar 2001 13:15:14 -0800 (PST) Received: (from stevev@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2CLFDr16375; Mon, 12 Mar 2001 13:15:13 -0800 (PST) From: Steve VanDevender MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Message-ID: <15021.15457.744604.806407@darkwing.uoregon.edu> Date: Mon, 12 Mar 2001 13:15:13 -0800 To: starship-design@lists.uoregon.edu Subject: starship-design: Rex Finke's "Starflight Mechanics Notes" X-Mailer: VM 6.91 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Sender: owner-starship-design@lists.uoregon.edu Precedence: bulk Reply-To: Steve VanDevender List member Rex Finke has written a paper "Starflight Mechanics Notes" which collects and summarizes many of the major physics and engineering topics discussed earlier in starship-design. As the paper is a bit too large to post to the list directly, I'm offering it as part of the starship-design archive pages. He has provided both Microsoft Word and Postscript versions of the document. You can get the paper from: http://darkwing.uoregon.edu/~stevev/sd-archive/starflight.doc (Microsoft Word) http://darkwing.uoregon.edu/~stevev/sd-archive/starflight.ps (Postscript) I've also included links to the paper from the main starship-design archive web page, http://darkwing.uoregon.edu/~stevev/sd-archive/ --part1_4f.8b44028.27e05a2d_boundary-- From VM Thu Mar 15 21:34:13 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["9976" "Friday" "16" "March" "2001" "00:21:11" "EST" "DotarSojat@aol.com" "DotarSojat@aol.com" nil "233" "Re: Fwd: starship-design: Rex Finke's \"Starflight Mechanics Notes\"" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 9976 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2G5PJP18786 for starship-design-outgoing; Thu, 15 Mar 2001 21:25:19 -0800 (PST) Received: (from stevev@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2G5PIh18780 for starship-design@lists.uoregon.edu; Thu, 15 Mar 2001 21:25:18 -0800 (PST) Received: from imo-m01.mx.aol.com (imo-m01.mx.aol.com [64.12.136.4]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2G5LPf18130 for ; Thu, 15 Mar 2001 21:21:25 -0800 (PST) Received: from DotarSojat@aol.com by imo-m01.mx.aol.com (mail_out_v29.5.) id z.e1.11b4357e (3962) for ; Fri, 16 Mar 2001 00:21:11 -0500 (EST) Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 3.0 16-bit for Windows sub 38 Precedence: bulk Reply-To: DotarSojat@aol.com From: DotarSojat@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: Fwd: starship-design: Rex Finke's "Starflight Mechanics Notes" Date: Fri, 16 Mar 2001 00:21:11 EST Hi Kelly (et al) Thanks for the review of "Starflight Mechanics Notes." In my 3/7 cover letter that went with the original transmittal of the paper to starship-design I wrote, "I would be receptive to any suggestions on how to improve it or how to adapt it for any purpose you might see fit to use it." Speaking of my cover letter, it is not among the correspondence that Kelly forwarded. On the possibility that it has fallen by the wayside, I reproduce it here: >Hi all > >As a token of my appreciation for the privilege of participating >in Group discussions from March '96 to July '97, I have >assembled some of the Group email notes from that period on >starflight mechanics and propulsion issues into an integrated >paper, or monograph, or whatever, entitled "Starflight Mechanics >Notes." >..... >If the paper gets a positive response, I will send the Appendix >"An Engineering Review of Relativity for Interstellar Flight" >as an attachment to a separate email. > >From the Preface to the paper: >"This document is intended to gather in one place the answers >to the questions about starflight mechanics and propulsion >technologies raised by Group members in the first three years >of the Starship Design project. (The emphasis is not so much >on providing answers as it is on showing how to find answers.) > >"The intent of the documentation here has been to use only >selections from notes as originally posted and to reproduce >them as closely as possible, except where they were incorrect >or incomplete, or where they were inconsistent with other >postings. (A few useful facts have been added here and there >to make the write-up more comprehensive.) It was of primary >interest to capture and preserve the feeling of discovery that >accompanied the interactions of the members." > >I would be receptive to any suggestions on how to improve this >compilation or how to adapt it for any purpose you might see >fit to use it. > >I am not on the starship-design mailing list, so please direct >any comments to . > >Best Regards >Rex Finke In a message dated 3/13/01 9:50:52 AM, kgstarks writes: >Rex, >Just read your LIT starflight paper. Thanks for collecting it >together. I enjoyed doing it and reminiscing. >I noticed you sometimes forgot to include units. For example >in the MeV to speed table you didn't list the units for the >resulting speed, nor in all the definitions of the letters in >the equations. I hope you have a better example than this. (I wonder how many others don't know what the units of "beta" are, especially when there is a definition of "beta" about five lines above the table [p. 12].) The v and V on p. 13 are not end-product variables that need units; only the E1 and E2 are. >I'm not sure why you didn't include reaction rate numbers for >all the fusion reactions on page 14? Rather than my saying "...with the reaction rates...given for the first five reactions," I guess I should have said "...with the reaction rates given [in the Plasma Formulary only] for the first five reactions..." I didn't foresee this confusion. >You might want to include full names in quotes? (?) I don't know what "full names" you're talking about. (The "full names" of the contributors are given in the Preface.) >Quotes came with " >" at the start of each line; but since you >didn't add hard returns when you added them to the paper, they >now sometimes float in the sentences. I didn't see this in either the WORD or PostScript versions. I considered going to quotation marks at the beginning and end of each quote, but decided to keep the original email format so that I could distinguish quotes within postings from stand-alone quotes. What would you suggest (hard returns mess up WORD)? >I'ld argue with some of your implications that there's a >physics limit to the project. A nasty engineering to cost >limit, yes; but that would require a very differnt set of >solutions. OK, I'll concede; understatement is always better. Change "Human interstellar flight in a human lifetime is far beyond current physics/economics." to "Human interstellar flight in a human lifetime is far beyond current engineering/economics." (Hmm, the former version is a direct quote of the original posting, to which you didn't object at that time.) >For example my fuel sail concept (which you didn't mention) >with a assumption of greatly reduced automated systems costs. I never understood what distinguished it from the "Deceleration of a Sail Pushed by a Constant-Power Beam." >Or refueling at the target system to eliminate the need to >carry round trip fuel. I guess my primary consideration in the paper was "getting there." The problem of getting there is hard enough, without compounding it now with the complexities of getting back, too. (I'm not arguing here for a "suicide mission," I'm just saying that when we figure out how to "get there" within then-existing engineering/economics limitations, we'll probably have a better handle on how to "get back.") >Or using a lithium base fusion fuel to eliminate the need for >a tank. I included the Plasma Formulary reaction rates precisely to indicate the increasing difficulty in achieving controlled fusion with nuclei having higher atomic number (higher Coulomb barrier). I believe controlled fusion with any nuclei other than deuterons and tritons may be almost as far beyond the horizon of the Starship Design project as antimatter. (And the mass ratios for fusion rockets [see p. 37] are pretty daunting [e.g., 3,600 for a 24-yr one-way trip to an 8 lt-yr destination] without making any additional allowance for tankage weight.) >Or suplying power/fuel in flight from earth to eliminate having >to carry it. An encounter with a fuel pellet at a relative velocity upwards of a km/sec or so constitutes a hypervelocity impact, i.e., instant conversion of kinetic energy to heat. (I presume the ship must be going faster than the fuel pellets in order to catch up with them. Maybe the ship just scoops up puffs of gases? The details of how you proposed to do this must have been in some correspondence that I didn't access.) >I have a serious problem figuring out the beam power to thrust >relationships for something like a microwave sail system. On pp. 25, 31 and 53, I write: "2,940 megawatts of beam power per kg of thrust" for 100% conversion of beam power to thrust, and p. 31: "Note: a 'photon rocket' with the same light-beam power would have the same thrust [as a relativistic electron thruster]." >Even more problems understanding how the beamed energy can be >consentrated into a conversion system for retro thrust, and get >more retrothrust - then forward thrust from the sail? A >critical point since it seems counter-intuative. Ahh. GREAT point! Alarm bells ringing: INCONSISTENCY! INCONSISTENCY! (Where were you 4 years ago when we needed you?) Either (1) the 2,940 Mw of beam power per kg of thrust can't apply to all beams (all three pages: 25, 31 and 53), or (2) there is something wrong with the analysis on p. 49 of the retrothruster for deceleration of the beam-pushed sail. Fortunately for the beam-driven-sail-concept, number (1) turns out to be the case: While 2,940 Mw of photons or 2,940 Mw of 1,000-MeV, say, electrons give 1 kg of thrust, 2,940 Mw of 1,000-MeV protons give 1.6961 kg of thrust. The number of kg of thrust for 2,940 Mw of proton beam power is given by the value of [factor] on p. 49. The expression [factor] should be replaced with the name "RBE" (Relative Beam Effectiveness [with apologies to the radiological hazards people, to whom RBE means Relative Biological Effectiveness if I remember right]). The value of RBE is 1.0000 for photons and relativistic electrons, but for protons RBE increases as the exhaust velocity Vexh (in lt-yr/yr) is reduced, according to the following table: Vexh RBE 0.9 1.5954 (the example in the text on p. 49) 0.8 2.0000 0.7 2.4488 0.6 3.0000 0.5 3.7321 0.4 4.7913 0.3 6.5131 0.2 9.8990 0.1 19.9499 which makes the deceleration of the beam-pushed sail easier and easier to achieve as the exhaust velocity of the protons is made lower and lower. Remember, "deceleration is possible only if the efficiency 'eta' of conversion of received power to exhaust power is greater than" 1/RBE. (I hope Kevin is still around to be pleased by this.) As the Vexh is reduced, however, the deceleration rate is increased, the deceleration distance is shortened and the required mass ratio is increased (to be confirmed). Following this trend, the argument in the text regarding selection of the turnaround point should be extended to considering tradeoffs of choosing turnaround points later than the halfway point. (The value of the RBE for the 1,060.5-Mev-proton deceleration beam required to bring the sail/ship to a stop in the second half of the 7.95 lt-yr trip on p. 51 is 1.6640, so I should have used 2,940/1.6640 = 1,767 Mw/kgf, instead of 2,940 Mw/kgf, to calculate the required current for the retro-thruster on p. 53.) >(Oh, did anyone consider converting the microwaves to >electricity in the sail [rectena sail?] rather then reflecting >and concentrating it? Does this help?) I'd be surprised to learn that microwaves are converted to electricity in a rectenna, and not at its focus after having been reflected and concentrated. >You might want to look up conversino numbers for free-electron >and LED lasers. I beleave their conversion efficencies are >higher. Not sure though. This does not strike a responsive chord in my memory. >In general though a great summary. If I still had access to >the web site I'ld convert it to HTML and link it it. Thanks. Would HTML fix the floating ">"s? >Kelly After I have an appropriate number of reviews from list members, I'll incorporate the agreed-upon revisions in the text and resubmit the paper. Regards Rex From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["6576" "Friday" "16" "March" "2001" "18:50:43" "-0600" "L. Parker" "lparker@cacaphony.net" nil "146" "starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 6576 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2H0stJ10354 for starship-design-outgoing; Fri, 16 Mar 2001 16:54:55 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2H0srf10342 for ; Fri, 16 Mar 2001 16:54:53 -0800 (PST) Received: from broadsword (p438.gnt.com [204.49.91.54]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id SAA15068 for ; Fri, 16 Mar 2001 18:54:48 -0600 Message-ID: <000901c0ae7c$aee0f510$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: multipart/related; boundary="----=_NextPart_000_000A_01C0AE4A.64468510" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 Importance: Normal Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "Starship-Design \(E-mail\)" Subject: starship-design: Massively Distributed Computing for SETI Date: Fri, 16 Mar 2001 18:50:43 -0600 This is a multi-part message in MIME format. ------=_NextPart_000_000A_01C0AE4A.64468510 Content-Type: multipart/alternative; boundary="----=_NextPart_001_000B_01C0AE4A.64468510" ------=_NextPart_001_000B_01C0AE4A.64468510 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit This group does not deal a great deal with SETI, but this is a reference to a technical article that gives some good background on just why it is so hard to detect an extraterrestrial signal...and if you can infer, why a beam propelled starship isn't quite as easy as we think. http://www.computer.org/cise/articles/seti.htm Lee ------=_NextPart_001_000B_01C0AE4A.64468510 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
This group = does not deal a=20 great deal with SETI, but this is a reference to a technical article = that gives=20 some good background on just why it is so hard to detect an = extraterrestrial=20 signal...and if you can infer, why a beam propelled starship isn't quite = as easy=20 as  we think.
 
http://www.comput= er.org/cise/articles/seti.htm
 
Lee
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Sat, 17 Mar 2001 14:35:47 -0800 (PST) Received: from imo-r16.mx.aol.com (imo-r16.mx.aol.com [152.163.225.70]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2HMZkf12053 for ; Sat, 17 Mar 2001 14:35:46 -0800 (PST) Received: from KellySt@aol.com by imo-r16.mx.aol.com (mail_out_v29.5.) id z.a4.11754a49 (18406) for ; Sat, 17 Mar 2001 17:35:17 -0500 (EST) Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sat, 17 Mar 2001 17:35:16 EST In a message dated 3/16/01 6:56:27 PM, lparker@cacaphony.net writes: >This group does not deal a great deal with SETI, but this is a reference >to > >a technical article that gives some good background on just why it is so > >hard to detect an extraterrestrial signal...and if you can infer, why a >beam > >propelled starship isn't quite as easy as we think. > > > >http://www.computer.org/cise/articles/seti.htm > > > >Lee How does this relate to beamed power? From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["150" "Saturday" "17" "March" "2001" "16:49:54" "-0600" "L. Parker" "lparker@cacaphony.net" nil "6" "RE: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 150 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2HMpQ216061 for starship-design-outgoing; Sat, 17 Mar 2001 14:51:26 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2HMpOf16053 for ; Sat, 17 Mar 2001 14:51:25 -0800 (PST) Received: from broadsword (p459.gnt.com [204.49.91.75]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id QAA19914; Sat, 17 Mar 2001 16:51:17 -0600 Message-ID: <001c01c0af34$9f331860$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 In-Reply-To: Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: , Subject: RE: starship-design: Massively Distributed Computing for SETI Date: Sat, 17 Mar 2001 16:49:54 -0600 > How does this relate to beamed power? Relative motion in a three body system with relativistic effects....we barely have the computing power. Lee From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["722" "Saturday" "17" "March" "2001" "23:52:29" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "18" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 722 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2I4qcP12075 for starship-design-outgoing; Sat, 17 Mar 2001 20:52:38 -0800 (PST) Received: from imo-m09.mx.aol.com (imo-m09.mx.aol.com [64.12.136.164]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2I4qbf12066 for ; Sat, 17 Mar 2001 20:52:37 -0800 (PST) Received: from KellySt@aol.com by imo-m09.mx.aol.com (mail_out_v29.5.) id z.103.699201 (18558) for ; Sat, 17 Mar 2001 23:52:29 -0500 (EST) Message-ID: <103.699201.27e5990d@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sat, 17 Mar 2001 23:52:29 EST In a message dated 3/17/01 4:51:26 PM, lparker@cacaphony.net writes: >> How does this relate to beamed power? > >Relative motion in a three body system with relativistic effects....we >barely have the computing power. > >Lee Given the relative positions of the stars haven't moved visibly in thousands of years. We can aim a fixed vector. The only problem is earth orbit around the sun. If beam array isn't a ring around the sun, I.E. if its around a point in orbit, the ship would have to follow the beam in a helical course around a direct vector from the sun, toward the target star. No serious math needed, or really possible. We can't aim the beam because we can't know where the ship is to aim it at. From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2733" "Sunday" "18" "March" "2001" "08:41:38" "-0600" "L. Parker" "lparker@cacaphony.net" nil "55" "RE: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 2733 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IEodf20766 for starship-design-outgoing; Sun, 18 Mar 2001 06:50:39 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IEobf20760 for ; Sun, 18 Mar 2001 06:50:38 -0800 (PST) Received: from broadsword (p457.gnt.com [204.49.91.73]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id IAA06732 for ; Sun, 18 Mar 2001 08:50:35 -0600 Message-ID: <001d01c0afba$a23edae0$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 In-Reply-To: <103.699201.27e5990d@aol.com> Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: Subject: RE: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 08:41:38 -0600 > Given the relative positions of the stars haven't moved > visibly in thousands > of years. We can aim a fixed vector. The only problem is > earth orbit around > the sun. If beam array isn't a ring around the sun, I.E. if > its around a > point in orbit, the ship would have to follow the beam in a > helical course > around a direct vector from the sun, toward the target star. > > No serious math needed, or really possible. We can't aim the > beam because we > can't know where the ship is to aim it at. Actually, there is more to it than that. Lets start with the relative motion first. "Moved visibly" is not the same thing as haven't moved. All stars are in motion, they follow their own orbits about the center of the galaxy as I am sure you know. Our sun is in one such orbit, any target star is going to be in another orbit traveling at a different velocity. We cannot simply aim the beam at the star, the star will not be there when the beam arrives. We must aim the beam at where the star will be when the beam gets there. This is a non-trivial task considering that all distances to stars are currently _estimated_. Then you must add for the motion of the beam array in its orbit about Sol. As was stated by Kelly this induces a helical component, and if we are in orbit about Earth or some other planet, it induces another helical component. Although it is possible for the ship to correct its course for helical movement of the beam source, this involves tacking the sails to maintain a steady course on a continuous basis and involves an element of risk if we lose the beam entirely and it doesn't solve the other problem. That is actually the easiest problem to solve. The second problem involves Doppler drift. As the ship gains velocity, it begins to experience Doppler drift or "red shift". Unfortunately, the sail is composed of a material designed to reflect a particular wavelength of radiation. It may also reflect other wavelengths, but not with the same efficiency. Therefore the beam transmitter must be capable of tuning the output across a range of frequencies to keep the energy received by the sail at a constant frequency. This means we must know the exact speed, course and distance of the sail at all times, constantly update the targeting data for the sail, the beam source, and the sail's destination, all in four dimensions, one of which has at least one harmonic component if not two to compute a continually changing target solution and frequency solution for the beam. Any way we approach this, the solution is going to be compute intensive, and it involves many of the same types of calculations being done by the SETI team, which was why I found the article so interesting. Lee From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["8012" "Sunday" "18" "March" "2001" "16:30:19" "+0100" "Zenon Kulpa" "zkulpa@ippt.gov.pl" nil "163" "RE: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 8012 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IFX1X27735 for starship-design-outgoing; Sun, 18 Mar 2001 07:33:01 -0800 (PST) Received: from ippt.gov.pl (zmit1.ippt.gov.pl [148.81.53.8]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IFWxf27728 for ; Sun, 18 Mar 2001 07:32:59 -0800 (PST) Received: (from zkulpa@localhost) by ippt.gov.pl (8.8.5/8.7.3-zmit) id QAA04369 for starship-design@lists.uoregon.edu; Sun, 18 Mar 2001 16:30:19 +0100 (MET) Message-Id: <200103181530.QAA04369@ippt.gov.pl> Precedence: bulk Reply-To: Zenon Kulpa From: Zenon Kulpa Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: RE: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 16:30:19 +0100 (MET) > From owner-starship-design@lists.uoregon.edu Sun Mar 18 15:54:38 2001 > From: "L. Parker" > > > Given the relative positions of the stars haven't moved visibly > > in thousands of years. We can aim a fixed vector. > > The only problem is earth orbit around the sun. If beam array > > isn't a ring around the sun, I.E. if its around a > > point in orbit, the ship would have to follow the beam > > in a helical course around a direct vector from the sun, > > toward the target star. > > > > No serious math needed, or really possible. We can't aim > > the beam because we can't know where the ship is to aim it at. > > Actually, there is more to it than that. > > Lets start with the relative motion first. > > "Moved visibly" is not the same thing as haven't moved. All stars are in > motion, they follow their own orbits about the center of the galaxy as I am > sure you know. Our sun is in one such orbit, any target star is going to be > in another orbit traveling at a different velocity. > > We cannot simply aim the beam at the star, the star will not be there when > the beam arrives. We must aim the beam at where the star will be when the > beam gets there. This is a non-trivial task considering that all distances > to stars are currently _estimated_. > > Then you must add for the motion of the beam array in its orbit about Sol. > As was stated by Kelly this induces a helical component, and if we are in > orbit about Earth or some other planet, it induces another helical > component. Although it is possible for the ship to correct its course for > helical movement of the beam source, this involves tacking the sails to > maintain a steady course on a continuous basis and involves an element of > risk if we lose the beam entirely and it doesn't solve the other problem. > > That is actually the easiest problem to solve. The second problem involves > Doppler drift. As the ship gains velocity, it begins to experience Doppler > drift or "red shift". Unfortunately, the sail is composed of a material > designed to reflect a particular wavelength of radiation. It may also > reflect other wavelengths, but not with the same efficiency. Therefore the > beam transmitter must be capable of tuning the output across a range of > frequencies to keep the energy received by the sail at a constant > frequency. > > This means we must know the exact speed, course and distance > of the sail at all times, constantly update the targeting data > for the sail, the beam source, and the sail's destination, > all in four dimensions, one of which has at least one harmonic > component if not two to compute a continually changing > target solution and frequency solution for the beam. > > Any way we approach this, the solution is going to be compute > intensive, and it involves many of the same types of calculations > being done by the SETI team, which was why I found the article > so interesting. > Add to that the consequences of even small aim errors on interstellar distances. I would like to remind you of the "deviation tble" I have sent to the list some five years ago... Here it goes: ------------------------------------ >From zkulpa Thu Oct 24 16:49:07 1996 From: zkulpa (Zenon Kulpa) To: starship-design@lists.uoregon.edu Note that the table gives deviation at target due to the change of ORIENTATION of the beaming device, the sensitivity to change of its POSITION is, fortunately, far smaller. Actually the sensitivity factor for position change equals 1 (one) - how much the platform moves sideways, so much does the beam at target (after some years...). However, if the platform moves along the Sun-centered orbit, its velocity is of the order of tens of kilometers a second (see another table below), hence it must compensate for its change of position with appropriate change of orientation, and the latter must be VERY accurate (as the deviation table shows). Moreover, the change of orientation must change very accurately with the distance to the target ship. The latter, I am afraid, is hard to know exactly in real time at long distances (e.g., the acceleration/speed will vary due to many factors, among others the accuracy of aiming the beam [and hence the thrust], the distribution of unknown masses along the way [e.g., invisible gas clouds or stray brown dwarf nearby...]). ================================================================== The beaming platform must orbit the Sun, thus: a) It will move quite fast, depending on the distance from the Sun, e.g: Distance Orbit from Sun Velocity Remarks of [mln km] [km/s] ---------------------------------------------------------------- Mercury 60 50 good place for solar-powered lasers Earth 150 30 near home... Jupiter 800 13 lots of local resources & moons to mine Pluto 6000 5 rather too far... b) So, it must constantly change its aim if it is not going to miss the target by hundreds of kilometers every 10 sec or so... And by how much it must change the aim? I have compiled the table below, where: "Size" is the "principal" dimension of the laser/maser gun component (e.g., the length of the laser "tube", or the diameter of the deflecting mirror, or microvawe antenna dish); "Tilt" is the amount by which one end/edge of the gun component moves relative to the opposite one (in milimeters); "Angle" is the tilt angle (in radians) corresponding to this tilt; "Distance" is the distance to the target (in light years), and the table entries contain the "Sweep" (in kilometers), i.e. approximate distance by which the beam moves sideways at the target distance: We have: Sweep/Distance = Tilt/Size I.e. (for small angles): Sweep = Distance * Angle[radians] Angle = Tilt/Size For simplicity, in the table I have rounded the light year to 10^13 km (instead of more exact 9.4543*10^12 km). Size Tilt Angle | Distance to target [ly] [km] [mm] [rad] | 1 5 10 ----------------------+------------------------------------------------ 0.1 0.1 10^-6 | 10 000 000 50 000 000 100 000 000 km 1 10^-5 | 100 000 000 500 000 000 1 000 000 000 km 10 10^-4 | 1 000 000 000 5 000 000 000 10 000 000 000 km ----------------------+------------------------------------------------ 1 0.1 10^-7 | 1 000 000 5 000 000 10 000 000 km 1 10^-6 | 10 000 000 50 000 000 100 000 000 km 10 10^-5 | 100 000 000 500 000 000 1 000 000 000 km ----------------------+------------------------------------------------ 10 0.1 10^-8 | 100 000 500 000 1 000 000 km 1 10^-7 | 1 000 000 5 000 000 10 000 000 km 10 10^-6 | 10 000 000 50 000 000 100 000 000 km ----------------------+------------------------------------------------ 100 0.1 10^-9 | 10 000 50 000 100 000 km 1 10^-8 | 100 000 500 000 1 000 000 km 10 10^-7 | 1 000 000 5 000 000 10 000 000 km ----------------------------------------------------------------------- [Note: for mirrors you must MULTIPLY the result by 2] E.g., a 100-kilometer diameter microvawe dish tilted by only 1 mm (1/25th of an inch) at the edge, sweeps the beam at 1 ly distance by 100 000 (one HUNDRED thousand) kilometers! (i.e., almost one-third of the Earth-Moon distance) I am afraid that such deflections are easily obtainable by heat distortions of the structure or gravitational perturbation from an asteroid flying some million kilometers away... ================================================================== -- Zenon Kulpa From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["960" "Sunday" "18" "March" "2001" "10:09:38" "-0600" "L. Parker" "lparker@cacaphony.net" nil "23" "RE: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 960 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IGAqx03994 for starship-design-outgoing; Sun, 18 Mar 2001 08:10:52 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IGApf03982 for ; Sun, 18 Mar 2001 08:10:51 -0800 (PST) Received: from broadsword (p457.gnt.com [204.49.91.73]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id KAA14794 for ; Sun, 18 Mar 2001 10:10:50 -0600 Message-ID: <001f01c0afc5$d7c7fd80$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 In-Reply-To: <200103181530.QAA04369@ippt.gov.pl> Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: Subject: RE: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 10:09:38 -0600 > > E.g., a 100-kilometer diameter microvawe dish > tilted by only 1 mm (1/25th of an inch) at the edge, sweeps > the beam > at 1 ly distance by 100 000 (one HUNDRED thousand) kilometers! > (i.e., almost one-third of the Earth-Moon distance) > > I am afraid that such deflections are easily obtainable > by heat distortions of the structure or gravitational perturbation > from an asteroid flying some million kilometers away... Well it is obvious from what you just presented that a dish is out of the question. A phased array however is quite a different matter. Assuming that we are looking at a microwave beam as opposed to a laser, then we would only have to electronically steer the beam to correct for movement - as well as heat distortions, gravitational perturbations, etc., which also implies some sort of feedback loop to measure such things. By the way, this also just added another whopping chunk of computer processing.... Lee From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["919" "Friday" "16" "March" "2001" "22:30:35" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "20" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 919 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IGeiL10220 for starship-design-outgoing; Sun, 18 Mar 2001 08:40:44 -0800 (PST) Received: from main.jetnet.ab.ca (root@jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IGegf10210 for ; Sun, 18 Mar 2001 08:40:42 -0800 (PST) Received: from jetnet.ab.ca (dialin60.jetnet.ab.ca [207.153.6.60]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id JAA25378 for ; Sun, 18 Mar 2001 09:40:39 -0700 (MST) Message-ID: <3AB2F67B.D153684A@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: <001d01c0afba$a23edae0$0100a8c0@broadsword> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Fri, 16 Mar 2001 22:30:35 -0700 "L. Parker" wrote: > This means we must know the exact speed, course and distance of the sail at > all times, constantly update the targeting data for the sail, the beam > source, and the sail's destination, all in four dimensions, one of which has > at least one harmonic component if not two to compute a continually changing > target solution and frequency solution for the beam. > > Any way we approach this, the solution is going to be compute intensive, and > it involves many of the same types of calculations being done by the SETI > team, which was why I found the article so interesting. > > Lee This may be true but the beam's does not need to updated that much, I guess once a minute and that is mostly with the feq of the beam. -- "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1179" "Sunday" "18" "March" "2001" "18:01:41" "+0100" "Zenon Kulpa" "zkulpa@ippt.gov.pl" nil "25" "RE: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1179 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IH4MK14052 for starship-design-outgoing; Sun, 18 Mar 2001 09:04:22 -0800 (PST) Received: from ippt.gov.pl (zmit1.ippt.gov.pl [148.81.53.8]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IH4Kf14046 for ; Sun, 18 Mar 2001 09:04:20 -0800 (PST) Received: (from zkulpa@localhost) by ippt.gov.pl (8.8.5/8.7.3-zmit) id SAA04442 for starship-design@lists.uoregon.edu; Sun, 18 Mar 2001 18:01:41 +0100 (MET) Message-Id: <200103181701.SAA04442@ippt.gov.pl> Precedence: bulk Reply-To: Zenon Kulpa From: Zenon Kulpa Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: RE: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 18:01:41 +0100 (MET) > From owner-starship-design@lists.uoregon.edu Sun Mar 18 17:16:34 2001 > From: "L. Parker" > > > E.g., a 100-kilometer diameter microvawe dish > > tilted by only 1 mm (1/25th of an inch) at the edge, sweeps the beam > > at 1 ly distance by 100 000 (one HUNDRED thousand) kilometers! > > (i.e., almost one-third of the Earth-Moon distance) > > > > I am afraid that such deflections are easily obtainable > > by heat distortions of the structure or gravitational perturbation > > from an asteroid flying some million kilometers away... > > Well it is obvious from what you just presented that a dish is out of the > question. A phased array however is quite a different matter. > > Assuming that we are looking at a microwave beam as opposed to a laser, > then we would only have to electronically steer the beam to correct for > movement - as well as heat distortions, gravitational perturbations, etc., > which also implies some sort of feedback loop to measure such things. > Which seems also a quite nontrivial task, as the accuracies must be very high, and the phased array will probably have to be quite huge... -- Zenon Kulpa From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1085" "Friday" "16" "March" "2001" "22:57:01" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "25" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1085 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IH7Kr15395 for starship-design-outgoing; Sun, 18 Mar 2001 09:07:20 -0800 (PST) Received: from main.jetnet.ab.ca (jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IH7Hf15389 for ; Sun, 18 Mar 2001 09:07:18 -0800 (PST) Received: from jetnet.ab.ca (dialin60.jetnet.ab.ca [207.153.6.60]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id KAA26677 for ; Sun, 18 Mar 2001 10:07:05 -0700 (MST) Message-ID: <3AB2FCAD.783F40B4@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: <001f01c0afc5$d7c7fd80$0100a8c0@broadsword> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Fri, 16 Mar 2001 22:57:01 -0700 "L. Parker" wrote: > By the way, this also just added another whopping chunk of computer > processing.... Great I can sell a whole bunch of Free CPU's to Starship design and make lots of $$$. Assuming somebody develops a reusable 2 stage to orbit craft to get materials into space. I place my bets on a slightly different method of beam energy craft. 1) Develop Anti-matter production plants on orbit around the sun. 2) Develop in solar system large energy relays. 3) Develop simple to manufacture solar energy beam power units. This will permit simple expansion into the solar system. Anti-matter/fusion drive will permit transportation of energy relay units and simple exploratory craft of next bit of uncharted space. In time a second beamed plant could be transported and placed in orbit around the host star. Once a system of energy relays is completed then transportation can start to be developed. "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2013" "Sunday" "18" "March" "2001" "11:36:28" "-0600" "L. Parker" "lparker@cacaphony.net" nil "40" "RE: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 2013 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IHcTD21617 for starship-design-outgoing; Sun, 18 Mar 2001 09:38:29 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IHcSf21612 for ; Sun, 18 Mar 2001 09:38:28 -0800 (PST) Received: from broadsword (p457.gnt.com [204.49.91.73]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id LAA24132 for ; Sun, 18 Mar 2001 11:38:23 -0600 Message-ID: <002001c0afd2$122dfa90$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 In-Reply-To: <3AB2F67B.D153684A@jetnet.ab.ca> Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: Subject: RE: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 11:36:28 -0600 > This may be true but the beam's does not need to updated that > much, I guess > once a minute and that is mostly with the feq of the beam. As Zenon's post points out, this is all dependent upon the beam aperture and distance to target. I posted the relevant equations several years ago, they should be in the archives. Without actually sitting down and figuring it out, I would say that Zenon's guess at ten minutes would be the outside limit for retargeting in 3 dimensions. The frequency shift depends upon two things, the acceleration rate and the nature of the sail and how forgiving it is. Probably not less than every ten minutes though. A typical non-mobile phased array in use today has around 100,000 emitters. Each of which requires a separate solution. There is a limited ability to "group" them to reduce the computation load to manageable levels, which results in some tradeoffs in other areas, but since we aren't talking about using this as a sensor, the tradeoffs aren't relevant. Zenon's best case was a 100 km antenna, which is probably the one we should go with given the power densities we need. Since even relatively small airborne phased array antennas of approximately one meter square contain between 2000 and 3000 emitters, we can use the smaller number to estimate the number of emitters and therefore the computing power necessary. A 100 km antenna contains 10,000,000,000 m^2 * 2,000 emitters or 20,000,000,000,000 emitters each of which requires several Fourier transforms to update its targeting. The computers controlling the one meter square airborne radars are state of the art digital signal processors and we would need the equivalent of 20 billion DSPs to perform these computations for the emitter processing alone. Now factor in the overall targeting solution using the three body solution problem I began with and you begin to see the size of the problem. We haven't even touched on several other of Zenon's objections such as downrange beam degradation, etc. Lee From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1375" "Saturday" "17" "March" "2001" "00:35:05" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "26" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1375 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IIjIs06018 for starship-design-outgoing; Sun, 18 Mar 2001 10:45:18 -0800 (PST) Received: from main.jetnet.ab.ca (root@jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IIjFf06008 for ; Sun, 18 Mar 2001 10:45:16 -0800 (PST) Received: from jetnet.ab.ca (dialin60.jetnet.ab.ca [207.153.6.60]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id LAA01222 for ; Sun, 18 Mar 2001 11:45:07 -0700 (MST) Message-ID: <3AB313A9.CA032A29@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: <002001c0afd2$122dfa90$0100a8c0@broadsword> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sat, 17 Mar 2001 00:35:05 -0700 "L. Parker" wrote: > Zenon's best case was a 100 km antenna, which is probably the one we should > go with given the power densities we need. Since even relatively small > airborne phased array antennas of approximately one meter square contain > between 2000 and 3000 emitters, we can use the smaller number to estimate > the number of emitters and therefore the computing power necessary. First of with the power levels involved I don't expect to have a lot of very small emitters. Secondly since the array is so large, I expect the math can be simplified down, and since a block of emitters will have its own cpu for control a lot of calculations can be done locally. It may even be possible to have a incremental algorithm that updates partial factors with a recalculation every hour or so. Remember the scale -- HUGE distances to travel, thus a long time frame for travel. This is something that will take several generations to finish thus realistic goals must be set for each generation. I also expect that the fastest possible craft at this time (anti-matter drive) craft @ .4C for a one way trip would be .1C for a practical usable craft ie:Payload, and .05C for a beamed energy craft. -- "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["319" "Sunday" "18" "March" "2001" "12:38:48" "-0600" "L. Parker" "lparker@cacaphony.net" nil "10" "starship-design: VASIMR" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 319 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IJTev15514 for starship-design-outgoing; Sun, 18 Mar 2001 11:29:40 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IJTdf15504 for ; Sun, 18 Mar 2001 11:29:39 -0800 (PST) Received: from broadsword (p436.gnt.com [204.49.91.52]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id NAA04555 for ; Sun, 18 Mar 2001 13:29:38 -0600 Message-ID: <002101c0afe1$9d3c96f0$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "Starship-Design \(E-mail\)" Subject: starship-design: VASIMR Date: Sun, 18 Mar 2001 12:38:48 -0600 Another interesting paper: http://spaceflight.nasa.gov/mars/reference/aspl/2000_3751.pdf A 10 Kilowatt thruster is scheduled for the RTD mission in 2004. It will be a 10,000 isp thruster, making it the largest electric thruster ever used in space. A 30 Mw model could make the trip to Mars in just a few weeks. Lee From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["765" "Sunday" "18" "March" "2001" "14:33:35" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "35" "starship-design: Re: Dyson Spheres" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 765 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IJXoc16461 for starship-design-outgoing; Sun, 18 Mar 2001 11:33:50 -0800 (PST) Received: from imo-r11.mx.aol.com (imo-r11.mx.aol.com [152.163.225.65]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IJXnf16446 for ; Sun, 18 Mar 2001 11:33:49 -0800 (PST) Received: from KellySt@aol.com by imo-r11.mx.aol.com (mail_out_v29.5.) id 1.c9.e22814e (4564); Sun, 18 Mar 2001 14:33:35 -0500 (EST) Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: rbcathcart@msn.com, starship-design@lists.uoregon.edu Subject: starship-design: Re: Dyson Spheres Date: Sun, 18 Mar 2001 14:33:35 EST Thanks, I'll check it out, and forward your urls to the group. ;) Kelly Starks In a message dated 3/17/01 10:15:44 PM, rbcathcart@msn.com writes: >Dear Sir: > > > >You might enjoy our on-line report at: http://2100.org clik "World Space >Program", then clik "Fiction: Dyson Spheres...". > > > >Sincerely, > >Richard.
Get your FREE download of MSN Explorer at http://explorer.msn.com > > > >-------------------- >
Dear Sir:
You might enjoy our on-line >report at: http://2100.org clik "World Space Program", then clik "Fiction: >Dyson Spheres...".
Sincerely,
Richard. > >
>
Get your FREE download of MSN Explorer at http://explorer.msn.com >
From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["977" "Sunday" "18" "March" "2001" "14:33:39" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "20" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 977 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IJYt017467 for starship-design-outgoing; Sun, 18 Mar 2001 11:34:55 -0800 (PST) Received: from imo-r12.mx.aol.com (imo-r12.mx.aol.com [152.163.225.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IJYnf17457 for ; Sun, 18 Mar 2001 11:34:54 -0800 (PST) Received: from KellySt@aol.com by imo-r12.mx.aol.com (mail_out_v29.5.) id 7.59.8532750 (4564); Sun, 18 Mar 2001 14:33:39 -0500 (EST) Message-ID: <59.8532750.27e66793@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: zkulpa@ippt.gov.pl, starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 14:33:39 EST In a message dated 3/18/01 9:35:17 AM, zkulpa@ippt.gov.pl writes: >However, if the platform moves along the Sun-centered orbit, >its velocity is of the order of tens of kilometers a second >(see another table below), hence it must compensate >for its change of position with appropriate change of orientation, >and the latter must be VERY accurate (as the deviation table shows). >Moreover, the change of orientation must change very accurately >with the distance to the target ship. The latter, I am afraid, >is hard to know exactly in real time at long distances >(e.g., the acceleration/speed will vary due to many factors, >among others the accuracy of aiming the beam [and hence the >thrust], the distribution of unknown masses along the way >[e.g., invisible gas clouds or stray brown dwarf nearby...]). As a nit. Since we couldn't try anything like this over more then a couple tens of light years. We'ld know of any of the big clouds or small stellar objects. From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["4001" "Sunday" "18" "March" "2001" "14:33:38" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "98" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 4001 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IJXtZ16491 for starship-design-outgoing; Sun, 18 Mar 2001 11:33:55 -0800 (PST) Received: from imo-r12.mx.aol.com (imo-r12.mx.aol.com [152.163.225.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IJXsf16481 for ; Sun, 18 Mar 2001 11:33:54 -0800 (PST) Received: from KellySt@aol.com by imo-r12.mx.aol.com (mail_out_v29.5.) id z.92.11d497d0 (4564) for ; Sun, 18 Mar 2001 14:33:38 -0500 (EST) Message-ID: <92.11d497d0.27e66792@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 14:33:38 EST In a message dated 3/18/01 8:52:13 AM, lparker@cacaphony.net writes: >> Given the relative positions of the stars haven't moved >> visibly in thousands >> of years. We can aim a fixed vector. The only problem is >> earth orbit around >> the sun. If beam array isn't a ring around the sun, I.E. if >> its around a >> point in orbit, the ship would have to follow the beam in a >> helical course >> around a direct vector from the sun, toward the target star. >> >> No serious math needed, or really possible. We can't aim the >> beam because we >> can't know where the ship is to aim it at. > >Actually, there is more to it than that. > >Lets start with the relative motion first. > >"Moved visibly" is not the same thing as haven't moved. All stars are in >motion, they follow their own orbits about the center of the galaxy as >I am >sure you know. Our sun is in one such orbit, any target star is going to >be >in another orbit traveling at a different velocity. > >We cannot simply aim the beam at the star, the star will not be there when >the beam arrives. We must aim the beam at where the star will be when the >beam gets there. This is a non-trivial task considering that all distances >to stars are currently _estimated_. I can't see how this wouldn't be a trivial problem? Your not talking a high lateral movement, or any delta-V of the two stars. On the scale of the galaxy the two stars are right on top of one another. (A couple light years out of a 30-40 THOUSAND light year orbital radius.) > >Then you must add for the motion of the beam array in its orbit about Sol. >As was stated by Kelly this induces a helical component, and if we are >in >orbit about Earth or some other planet, it induces another helical >component. Although it is possible for the ship to correct its course for >helical movement of the beam source, this involves tacking the sails to >maintain a steady course on a continuous basis and involves an element >of >risk if we lose the beam entirely and it doesn't solve the other problem. Already covered the other problem. Tacking, or otherwise manuvering into the path of the beam is nessisary. If you fly out of the beam you'll need secoundary motors to manuver back into the beam. You'll need manuvering engines anyway for in systems work. Note, I've always assumed beam dispersal would make beamed power useless out more then a few light months from the transmitters (hence my fuel-sail idea). > >That is actually the easiest problem to solve. The second problem involves >Doppler drift. As the ship gains velocity, it begins to experience Doppler >drift or "red shift". Unfortunately, the sail is composed of a material >designed to reflect a particular wavelength of radiation. It may also >reflect other wavelengths, but not with the same efficiency. Therefore >the >beam transmitter must be capable of tuning the output across a range of >frequencies to keep the energy received by the sail at a constant frequency. I'm wondering how bad the dopler shift would disrupt the acceleration of a sail driven craft? >This means we must know the exact speed, course and distance of the sail >at >all times, constantly update the targeting data for the sail, the beam >source, and the sail's destination, all in four dimensions, one of which >has >at least one harmonic component if not two to compute a continually changing >target solution and frequency solution for the beam. > >Any way we approach this, the solution is going to be compute intensive, >and >it involves many of the same types of calculations being done by the SETI >team, which was why I found the article so interesting. > >Lee It is completly impossible that we would be able to precisely know the possition and sppeed of a ship months or years after the last view of it. Any system that has to depend on that would be to dangerous and unrelyable. So the system must be designed to not need to rely on that degree of precision to function. Kelly From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["921" "Saturday" "17" "March" "2001" "02:05:23" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "23" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 921 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IKFdG26592 for starship-design-outgoing; Sun, 18 Mar 2001 12:15:39 -0800 (PST) Received: from main.jetnet.ab.ca (root@jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IKFZf26575 for ; Sun, 18 Mar 2001 12:15:35 -0800 (PST) Received: from jetnet.ab.ca (dialin60.jetnet.ab.ca [207.153.6.60]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id NAA05177 for ; Sun, 18 Mar 2001 13:15:25 -0700 (MST) Message-ID: <3AB328D3.93723245@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: <92.11d497d0.27e66792@aol.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu To: "starship-design@lists.uoregon.edu" Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sat, 17 Mar 2001 02:05:23 -0700 KellySt@aol.com wrote: > Note, I've always assumed beam dispersal would make beamed power useless out > more then a few light months from the transmitters (hence my fuel-sail idea). I expect that is over optimistic. A few light days I guess would be practical. Most likely acceleration will be near and in the solar system but the real limiting factor is heat. Heat is hard to get rid of in space. > > It is completly impossible that we would be able to precisely know the > possition and sppeed of a ship months or years after the last view of it. > Any system that has to depend on that would be to dangerous and unrelyable. > So the system must be designed to not need to rely on that degree of > precision to function. I agree. > Kelly -- "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2721" "Sunday" "18" "March" "2001" "15:50:50" "-0600" "L. Parker" "lparker@cacaphony.net" nil "65" "RE: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 2721 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2ILqmQ22579 for starship-design-outgoing; Sun, 18 Mar 2001 13:52:48 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2ILqkf22571 for ; Sun, 18 Mar 2001 13:52:47 -0800 (PST) Received: from broadsword (p436.gnt.com [204.49.91.52]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id PAA20322 for ; Sun, 18 Mar 2001 15:52:42 -0600 Message-ID: <002201c0aff5$99c162d0$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 In-Reply-To: <92.11d497d0.27e66792@aol.com> Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: Subject: RE: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 15:50:50 -0600 > I can't see how this wouldn't be a trivial problem? Your not > talking a high > lateral movement, or any delta-V of the two stars. On the > scale of the > galaxy the two stars are right on top of one another. (A > couple light years > out of a 30-40 THOUSAND light year orbital radius.) It all depends upon which star you choose, some do display quite a bit of proper motion relative to us. However, you are correct, that most do not, IF you average for the effects of our own planetary orbit. > > > >Then you must add for the motion of the beam array in its > orbit about Sol. > > Already covered the other problem. Tacking, or otherwise > manuvering into the > path of the beam is nessisary. If you fly out of the beam > you'll need > secoundary motors to manuver back into the beam. You'll need > manuvering > engines anyway for in systems work. Tacking is quite possible, it also puts unnecessary stress upon a rather delicate craft. If it can be done at the emitter, it should be done there. Repair from Earth is easy for the emitter. If you break a halyard between the stars, no amount of paddling is going to get you home. > Note, I've always assumed beam dispersal would make beamed > power useless out > more then a few light months from the transmitters (hence my > fuel-sail idea). Actually, this is probably the best point of all in FAVOR of beamed propulsion. Remember that aperture size controls beam width and with an array of emitters in orbit, we could have an aperture as large as we wanted, just pick the proper orbit. There are some trivial corollary problems such as maintaining the emitters' orbits, but I can think of several solutions. > I'm wondering how bad the dopler shift would disrupt the > acceleration of a > sail driven craft? As I said, it depends upon how fast we get the sail going, what the acceleration rate is, and what type of beamed power we use. A solar pumped optical laser, or for that matter, just a whole bunch of solar collimators (fancy mirrors) would due the trick without having to worry quite so much about Doppler effects. > It is completly impossible that we would be able to precisely > know the > possition and sppeed of a ship months or years after the last > view of it. > Any system that has to depend on that would be to dangerous > and unrelyable. > So the system must be designed to not need to rely on that degree of > precision to function. Depends upon what you mean by "precisely". Yes there would be an ever growing feedback problem. But barring some catastrophic course change event, we should be able to build a good enough profile while the sail is still within reasonable communication range that we can compensate for the lag. Lee From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["537" "Sunday" "18" "March" "2001" "15:30:52" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "11" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 537 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IMfBP05045 for starship-design-outgoing; Sun, 18 Mar 2001 14:41:11 -0800 (PST) Received: from main.jetnet.ab.ca (root@jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IMfAf05035 for ; Sun, 18 Mar 2001 14:41:10 -0800 (PST) Received: from jetnet.ab.ca (dialin41.jetnet.ab.ca [207.153.6.41]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id PAA11708 for ; Sun, 18 Mar 2001 15:41:07 -0700 (MST) Message-ID: <3AB5371C.901C298A@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: <002201c0aff5$99c162d0$0100a8c0@broadsword> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 15:30:52 -0700 "L. Parker" wrote: > It all depends upon which star you choose, some do display quite a bit of > proper motion relative to us. However, you are correct, that most do not, IF > you average for the effects of our own planetary orbit . Does anybody know of any programs that do that, showing positions of the stars in the past or the future from any point in space? -- "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["998" "Sunday" "18" "March" "2001" "15:08:52" "-0800" "Steve VanDevender" "stevev@efn.org" nil "19" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 998 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2IN8W511477 for starship-design-outgoing; Sun, 18 Mar 2001 15:08:33 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2IN8Vf11445 for ; Sun, 18 Mar 2001 15:08:31 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f2IN8Uq20974 for ; Sun, 18 Mar 2001 15:08:30 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f2IN8ri09497; Sun, 18 Mar 2001 15:08:53 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15029.16388.609710.138719@localhost.efn.org> In-Reply-To: <3AB5371C.901C298A@jetnet.ab.ca> References: <002201c0aff5$99c162d0$0100a8c0@broadsword> <3AB5371C.901C298A@jetnet.ab.ca> X-Mailer: VM 6.92 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 15:08:52 -0800 Ben Franchuk writes: > "L. Parker" wrote: > > It all depends upon which star you choose, some do display quite a bit of > > proper motion relative to us. However, you are correct, that most do not, IF > > you average for the effects of our own planetary orbit > . > Does anybody know of any programs that do that, showing positions of the stars > in the past or the future from any point in space? Any good astronomical ephemeris program should do that, for the stars whose proper motions are known. There's a very nice program called XEphem that runs on UNIX systems. Also, Lee, proper motion is defined as a star's average angular motion against the sky over a multi-year period, not any instaneous measurement of relative velocity. In general the proper motion of a star has to be determined by observations of a star's movement over long periods, subtracting out various things like relativistic aberration, parallax, and other short-term variations in the star's apparent position. From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["188" "Sunday" "18" "March" "2001" "17:44:55" "-0600" "L. Parker" "lparker@cacaphony.net" nil "11" "RE: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 188 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2INkV121387 for starship-design-outgoing; Sun, 18 Mar 2001 15:46:31 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2INkTf21380 for ; Sun, 18 Mar 2001 15:46:30 -0800 (PST) Received: from broadsword (p436.gnt.com [204.49.91.52]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id RAA00780 for ; Sun, 18 Mar 2001 17:46:24 -0600 Message-ID: <002501c0b005$79aefc90$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 In-Reply-To: <3AB5371C.901C298A@jetnet.ab.ca> Importance: Normal Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: Subject: RE: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 17:44:55 -0600 > Does anybody know of any programs that do that, showing > positions of the stars > in the past or the future from any point in space? Try: http://members.nova.org/~sol/chview/ Lee From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1050" "Sunday" "18" "March" "2001" "16:46:26" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "21" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1050 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2INukO24577 for starship-design-outgoing; Sun, 18 Mar 2001 15:56:46 -0800 (PST) Received: from main.jetnet.ab.ca (root@jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2INuif24571 for ; Sun, 18 Mar 2001 15:56:45 -0800 (PST) Received: from jetnet.ab.ca (dialin40.jetnet.ab.ca [207.153.6.40]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id QAA15365 for ; Sun, 18 Mar 2001 16:56:40 -0700 (MST) Message-ID: <3AB548D2.5DBE7F27@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: <002201c0aff5$99c162d0$0100a8c0@broadsword> <3AB5371C.901C298A@jetnet.ab.ca> <15029.16388.609710.138719@localhost.efn.org> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu To: "starship-design@lists.uoregon.edu" Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 16:46:26 -0700 Steve VanDevender wrote: > Any good astronomical ephemeris program should do that, for the stars > whose proper motions are known. There's a very nice program called > XEphem that runs on UNIX systems. > > Also, Lee, proper motion is defined as a star's average angular motion > against the sky over a multi-year period, not any instaneous measurement > of relative velocity. In general the proper motion of a star has to be > determined by observations of a star's movement over long periods, > subtracting out various things like relativistic aberration, parallax, > and other short-term variations in the star's apparent position. But alas the program has the limit of about 5,000 BP ( or what ever year 1 is for astronomers). Part of the time range I am looking for is to 35,000 BP. No real reason other than I wonder what things looked like during the last ice age. -- "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["644" "Sunday" "18" "March" "2001" "18:37:50" "-0800" "Steve VanDevender" "stevev@efn.org" nil "12" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 644 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2J2bki10999 for starship-design-outgoing; Sun, 18 Mar 2001 18:37:46 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2J2bif10994 for ; Sun, 18 Mar 2001 18:37:44 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f2J2bhq09117; Sun, 18 Mar 2001 18:37:43 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f2J2c6T09829; Sun, 18 Mar 2001 18:38:06 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15029.28926.154844.602893@localhost.efn.org> In-Reply-To: <3AB548D2.5DBE7F27@jetnet.ab.ca> References: <002201c0aff5$99c162d0$0100a8c0@broadsword> <3AB5371C.901C298A@jetnet.ab.ca> <15029.16388.609710.138719@localhost.efn.org> <3AB548D2.5DBE7F27@jetnet.ab.ca> X-Mailer: VM 6.92 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: Ben Franchuk Cc: "starship-design@lists.uoregon.edu" Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 18:37:50 -0800 Ben Franchuk writes: > But alas the program has the limit of about 5,000 BP ( or what ever > year 1 is for astronomers). Part of the time range I am looking > for is to 35,000 BP. No real reason other than I wonder what things > looked like during the last ice age. There's a fairly high uncertainty in proper motion measurements for most stars. Even if you got a program to show you the sky adjusted for stellar proper motion in 35,000 BP, it might not be that accurate. Apparently the program you tried limits the time range it will display to avoid going outside the range where the uncertainty would accumulate to undesirable levels. From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1842" "Sunday" "18" "March" "2001" "19:52:52" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "39" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1842 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2J33Jf17757 for starship-design-outgoing; Sun, 18 Mar 2001 19:03:19 -0800 (PST) Received: from main.jetnet.ab.ca (root@jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2J33Bf17745 for ; Sun, 18 Mar 2001 19:03:12 -0800 (PST) Received: from jetnet.ab.ca (dialin58.jetnet.ab.ca [207.153.6.58]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id UAA23822 for ; Sun, 18 Mar 2001 20:03:03 -0700 (MST) Message-ID: <3AB57484.65087372@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: <002201c0aff5$99c162d0$0100a8c0@broadsword> <3AB5371C.901C298A@jetnet.ab.ca> <15029.16388.609710.138719@localhost.efn.org> <3AB548D2.5DBE7F27@jetnet.ab.ca> <15029.28926.154844.602893@localhost.efn.org> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu CC: "starship-design@lists.uoregon.edu" Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 19:52:52 -0700 Steve VanDevender wrote: > > Ben Franchuk writes: > > But alas the program has the limit of about 5,000 BP ( or what ever > > year 1 is for astronomers). Part of the time range I am looking > > for is to 35,000 BP. No real reason other than I wonder what things > > looked like during the last ice age. > > There's a fairly high uncertainty in proper motion measurements for most > stars. Even if you got a program to show you the sky adjusted for > stellar proper motion in 35,000 BP, it might not be that accurate. > Apparently the program you tried limits the time range it will display > to avoid going outside the range where the uncertainty would accumulate > to undesirable levels. While 35,000 BP I expect to be the limit of any program, astronomical calculations to say 15,000 BP would be very useful of common astronomical events like sun/planetary movements and near by star motion in understanding possible pre-history and the events in the heavens at that time. Here is the link that got me thinking about pre-history. http://www.astrologyworldnews.com/go/offsite.asp?url=http://news.bbc.co.uk/hi/english/sci/tech/newsid_871000/871930.stm " prehistoric map of the night sky has been discovered on the walls of the famous painted caves at Lascaux in central France. The map, which is thought to date back 16,500 years, shows three bright stars known today as the Summer Triangle. " I want to know if such group of stars could be seen during the summer? Maybe it was a some other time of year that it could be seen. While one can't check if it was a star map, one can indeed check if the heavens did look that way. -- "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1806" "Sunday" "18" "March" "2001" "22:04:32" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "34" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1806 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2J35Q918315 for starship-design-outgoing; Sun, 18 Mar 2001 19:05:26 -0800 (PST) Received: from imo-m08.mx.aol.com (imo-m08.mx.aol.com [64.12.136.163]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2J35Pf18299 for ; Sun, 18 Mar 2001 19:05:25 -0800 (PST) Received: from KellySt@aol.com by imo-m08.mx.aol.com (mail_out_v29.5.) id z.e3.11e48433 (4390); Sun, 18 Mar 2001 22:04:32 -0500 (EST) Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: bfranchuk@jetnet.ab.ca CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 22:04:32 EST In a message dated 3/18/01 12:46:14 PM, bfranchuk@jetnet.ab.ca writes: >> Zenon's best case was a 100 km antenna, which is probably the one we >should >> go with given the power densities we need. Since even relatively small >> airborne phased array antennas of approximately one meter square contain >> between 2000 and 3000 emitters, we can use the smaller number to estimate >> the number of emitters and therefore the computing power necessary. > >First of with the power levels involved I don't expect to have a lot of >very small emitters. Secondly since the array is so large, I expect the >math can be simplified down, and since a block of emitters will have its >own cpu for control a lot of calculations can be done locally. It may even >be possible to have a incremental algorithm that updates partial factors >with a recalculation every hour or so. >Remember the scale -- HUGE distances to travel, thus a long time frame >for travel. This is something that will take several generations to finish >thus realistic goals must be set for each generation. >I also expect that the fastest possible craft at this time (anti-matter >drive) >craft @ .4C for a one way trip would be .1C for a practical usable >craft ie:Payload, and .05C for a beamed energy craft. I was getting significantly better speed numbers. More importantly a mulit generation ship is a collosal waste. It requires a vastly larger, heavier, more complicated ship. So much so, that the same propulsion gear could get you there in a fraction of the time. Hence a small craft that would get there in years, would be easier to do then one that would get there in decades. Also trips that take generations are assured to get their AFTER ships sent out decades after it left. Assuming anyone would bother to send them. From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1355" "Sunday" "18" "March" "2001" "20:15:42" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "28" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1355 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2J3Q2j22961 for starship-design-outgoing; Sun, 18 Mar 2001 19:26:02 -0800 (PST) Received: from main.jetnet.ab.ca (root@jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2J3Pwf22946 for ; Sun, 18 Mar 2001 19:25:59 -0800 (PST) Received: from jetnet.ab.ca (dialin58.jetnet.ab.ca [207.153.6.58]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id UAA24820 for ; Sun, 18 Mar 2001 20:25:53 -0700 (MST) Message-ID: <3AB579DE.6F43A6B6@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 20:15:42 -0700 KellySt@aol.com wrote: >> I was getting significantly better speed numbers. More importantly a mulit > generation ship is a collosal waste. It requires a vastly larger, heavier, > more complicated ship. So much so, that the same propulsion gear could get > you there in a fraction of the time. Hence a small craft that would get > there in years, would be easier to do then one that would get there in > decades. I favor the slower ships because I can't see a practical high speed drive. > Also trips that take generations are assured to get their AFTER ships sent > out decades after it left. Assuming anyone would bother to send them. That is based on the premise a FAST drive is possible. Lets face it any interstellar travel will require pushing all known technology to the limit, and it is hard to say exactly what will be possible in the future because factors can change suddenly. I think several designs need to be studied. For example suspension of life that is not possible now could be possible in the future with the study of DNA and other biological processes. This could favor slower ship for bulk transport and a high speed craft for living material. Ben. -- "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1196" "Sunday" "18" "March" "2001" "20:04:26" "-0800" "Steve VanDevender" "stevev@efn.org" nil "25" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1196 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2J44Q203146 for starship-design-outgoing; Sun, 18 Mar 2001 20:04:26 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2J44Pf03139 for ; Sun, 18 Mar 2001 20:04:25 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f2J44Nq28398; Sun, 18 Mar 2001 20:04:23 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f2J44jD10098; Sun, 18 Mar 2001 20:04:45 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15029.34122.184581.36889@localhost.efn.org> In-Reply-To: <3AB57484.65087372@jetnet.ab.ca> References: <002201c0aff5$99c162d0$0100a8c0@broadsword> <3AB5371C.901C298A@jetnet.ab.ca> <15029.16388.609710.138719@localhost.efn.org> <3AB548D2.5DBE7F27@jetnet.ab.ca> <15029.28926.154844.602893@localhost.efn.org> <3AB57484.65087372@jetnet.ab.ca> X-Mailer: VM 6.92 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: Ben Franchuk Cc: "starship-design@lists.uoregon.edu" Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Sun, 18 Mar 2001 20:04:26 -0800 Ben Franchuk writes: > Here is the link that got me thinking about pre-history. > > http://www.astrologyworldnews.com/go/offsite.asp?url=http://news.bbc.co.uk/hi/english/sci/tech/newsid_871000/871930.stm > > " prehistoric map of the night sky has been discovered on the walls of the > famous painted caves at Lascaux in central France. > The map, which is thought to date back > 16,500 years, shows three bright stars > known today as the Summer Triangle. > " > I want to know if such group of stars could be seen during the summer? The "Summer Triangle" is the stars Vega, Deneb, and Altair, which are easily visible in the summer months in the northern hemisphere. They would not have significantly changed their relative positions to each other in the past few tens of thousands of years. > Maybe it was a some other time of year that it could be seen. > While one can't check if it was a star map, one can indeed check if the > heavens did look that way. >From what XEphem shows me, 16,500 years ago in France the stars Vega, Deneb, and Altair would all have been circumpolar, meaning they would have been visible at night any time of year. From VM Mon Mar 19 10:19:40 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2692" "Monday" "19" "March" "2001" "15:55:26" "+0100" "Zenon Kulpa" "zkulpa@ippt.gov.pl" nil "61" "RE: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 2692 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2JEwDt01705 for starship-design-outgoing; Mon, 19 Mar 2001 06:58:13 -0800 (PST) Received: from ippt.gov.pl (zmit1.ippt.gov.pl [148.81.53.8]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2JEw7f01693 for ; Mon, 19 Mar 2001 06:58:11 -0800 (PST) Received: (from zkulpa@localhost) by ippt.gov.pl (8.8.5/8.7.3-zmit) id PAA05231 for starship-design@lists.uoregon.edu; Mon, 19 Mar 2001 15:55:26 +0100 (MET) Message-Id: <200103191455.PAA05231@ippt.gov.pl> Precedence: bulk Reply-To: Zenon Kulpa From: Zenon Kulpa Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: RE: starship-design: Massively Distributed Computing for SETI Date: Mon, 19 Mar 2001 15:55:26 +0100 (MET) > From owner-starship-design@lists.uoregon.edu Sun Mar 18 18:37:42 2001 > From: "L. Parker" > [...] > Without actually sitting down and figuring it out, I would say > that Zenon's guess at ten minutes would be the outside limit > for retargeting in 3 dimensions. ? Sorry, I did not make any guesses concerning the retargeting rate. I do not know from where you took these ten minutes... > From owner-starship-design@lists.uoregon.edu Sun Mar 18 20:34:26 2001 > From: KellySt@aol.com > > In a message dated 3/18/01 8:52:13 AM, lparker@cacaphony.net writes: > [...] > >"Moved visibly" is not the same thing as haven't moved. All stars are in > >motion, they follow their own orbits about the center of the galaxy > >as I am sure you know. Our sun is in one such orbit, any target star > >is going to be in another orbit traveling at a different velocity. > > > >We cannot simply aim the beam at the star, the star will not be there when > >the beam arrives. We must aim the beam at where the star will be when the > >beam gets there. This is a non-trivial task considering that all distances > >to stars are currently _estimated_. > > I can't see how this wouldn't be a trivial problem? Your not talking > a high lateral movement, or any delta-V of the two stars. > On the scale of the galaxy the two stars are right on top > of one another. (A couple light years > out of a 30-40 THOUSAND light year orbital radius.) > For a starship what is important is not the _relative_ change of the star position with respect to its distance from the center of the Galaxy, but _absolute_ change of its position (in light years, say). If the star moves a light year with respect to the aim of the starship, the starship must simply travel this additional light year (laterally, say) in order to catch it, no matter how far (or near) the center of the Galaxy is. [...] > Tacking, or otherwise manuvering into the path of the beam > is nessisary. If you fly out of the beam you'll need > secoundary motors to manuver back into the beam. > You'll need manuvering engines anyway for in systems work. > Notice however, that the lateral movement of the beam due to any jitter od the beaming antenna will be rather rapid - in fact, it may easily exceed the speed of light! E.g, for a 100 km antenna, its tilt with the speed of 1 mm per second causes the beam at 1 ly to move laterally with the speed of 100 000 km/s, i.e., 0.33 c... Also, helical tacking to follow the orbital path (around the Sun, say) of the beaming antenna will use lots of additional fuel, since it must provide constant acceleration to curve the path appropriately. -- Zenon Kulpa From VM Mon Mar 19 16:26:53 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["3372" "Monday" "19" "March" "2001" "19:19:38" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "88" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 3372 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2K0JnS27750 for starship-design-outgoing; Mon, 19 Mar 2001 16:19:49 -0800 (PST) Received: from imo-m07.mx.aol.com (imo-m07.mx.aol.com [64.12.136.162]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2K0Jmf27742 for ; Mon, 19 Mar 2001 16:19:48 -0800 (PST) Received: from KellySt@aol.com by imo-m07.mx.aol.com (mail_out_v29.5.) id z.d5.3d28de4 (24896) for ; Mon, 19 Mar 2001 19:19:38 -0500 (EST) Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Mon, 19 Mar 2001 19:19:38 EST In a message dated 3/18/01 3:53:39 PM, lparker@cacaphony.net writes: >> I can't see how this wouldn't be a trivial problem? Your not >> talking a high >> lateral movement, or any delta-V of the two stars. On the >> scale of the >> galaxy the two stars are right on top of one another. (A >> couple light years >> out of a 30-40 THOUSAND light year orbital radius.) > >It all depends upon which star you choose, some do display quite a bit >of >proper motion relative to us. However, you are correct, that most do not, >IF >you average for the effects of our own planetary orbit. Agreed. Actually, how many if any do show serious "drift"? >> >Then you must add for the motion of the beam array in its >> orbit about Sol. >> >> Already covered the other problem. Tacking, or otherwise >> manuvering into the >> path of the beam is nessisary. If you fly out of the beam >> you'll need >> secoundary motors to manuver back into the beam. You'll need >> manuvering >> engines anyway for in systems work. > >Tacking is quite possible, it also puts unnecessary stress upon a rather >delicate craft. If it can be done at the emitter, it should be done there. >Repair from Earth is easy for the emitter. If you break a halyard between >the stars, no amount of paddling is going to get you home. True, but if you have a problem with the ship that will let it follow the beam, but not stay on the correct acceleratio schedule. An untracked beam will still work as well. One optimized for a ship at a precise position, might be useless. >> Note, I've always assumed beam dispersal would make beamed >> power useless out >> more then a few light months from the transmitters (hence my >> fuel-sail idea). > >Actually, this is probably the best point of all in FAVOR of beamed >propulsion. Remember that aperture size controls beam width and with an >array of emitters in orbit, we could have an aperture as large as we wanted, >just pick the proper orbit. There are some trivial corollary problems such >as maintaining the emitters' orbits, but I can think of several solutions. I don't follow how that relates to my comments about beam dispersal or fuel/sail? >> I'm wondering how bad the dopler shift would disrupt the >> acceleration of a >> sail driven craft? > >As I said, it depends upon how fast we get the sail going, what the >acceleration rate is, and what type of beamed power we use. A solar pumped >optical laser, or for that matter, just a whole bunch of solar collimators >(fancy mirrors) would due the trick without having to worry quite so much >about Doppler effects. > >> It is completly impossible that we would be able to precisely >> know the >> possition and sppeed of a ship months or years after the last >> view of it. >> Any system that has to depend on that would be to dangerous >> and unrelyable. >> So the system must be designed to not need to rely on that degree of >> precision to function. > >Depends upon what you mean by "precisely". Yes there would be an ever >growing feedback problem. But barring some catastrophic course change event, >we should be able to build a good enough profile while the sail is still >within reasonable communication range that we can compensate for the lag. > >Lee I would assume this was only possible within a couple light weeks or perhaps months. That would seriously restrict speed. From VM Tue Mar 20 17:00:15 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2372" "Tuesday" "20" "March" "2001" "19:54:34" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "63" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 2372 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2L0tTm05770 for starship-design-outgoing; Tue, 20 Mar 2001 16:55:29 -0800 (PST) Received: from imo-r12.mx.aol.com (imo-r12.mx.aol.com [152.163.225.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2L0tSC05762 for ; Tue, 20 Mar 2001 16:55:28 -0800 (PST) Received: from KellySt@aol.com by imo-r12.mx.aol.com (mail_out_v29.5.) id 7.12.a60f745 (3315); Tue, 20 Mar 2001 19:54:36 -0500 (EST) Message-ID: <12.a60f745.27e955ca@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: zkulpa@ippt.gov.pl, starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Tue, 20 Mar 2001 19:54:34 EST >[...] >> >"Moved visibly" is not the same thing as haven't moved. All stars are >in >> >motion, they follow their own orbits about the center of the galaxy >> >as I am sure you know. Our sun is in one such orbit, any target star >> >is going to be in another orbit traveling at a different velocity. >> > >> >We cannot simply aim the beam at the star, the star will not be there >when >> >the beam arrives. We must aim the beam at where the star will be when >the >> >beam gets there. This is a non-trivial task considering that all distances >> >to stars are currently _estimated_. >> >> I can't see how this wouldn't be a trivial problem? Your not talking >> a high lateral movement, or any delta-V of the two stars. >> On the scale of the galaxy the two stars are right on top >> of one another. (A couple light years >> out of a 30-40 THOUSAND light year orbital radius.) >> >For a starship what is important is not the _relative_ change >of the star position with respect to its distance from the center >of the Galaxy, but _absolute_ change of its position >(in light years, say). If the star moves a light year with respect >to the aim of the starship, the starship must simply travel >this additional light year (laterally, say) in order to catch it, >no matter how far (or near) the center of the Galaxy is. Relative movement is related to the degree of difference of the orbit. In this case the fractinal difference would be trivial. As long as the two stars don't move relative to one another - effectivly they can be treated as unmoving for nav purposes. >[...] >> Tacking, or otherwise manuvering into the path of the beam >> is nessisary. If you fly out of the beam you'll need >> secoundary motors to manuver back into the beam. >> You'll need manuvering engines anyway for in systems work. >> >Notice however, that the lateral movement of the beam due to >any jitter od the beaming antenna will be rather rapid - in fact, >it may easily exceed the speed of light! So don't jitter. >Also, helical tacking to follow the orbital path (around the Sun, say) >of the beaming antenna will use lots of additional fuel, >since it must provide constant acceleration to curve >the path appropriately. Or you'ld need to tack the sail. Eiather way the fuel costs would be trivial compared to the main boost. > >-- Zenon Kulpa From VM Tue Mar 20 17:00:56 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1612" "Tuesday" "20" "March" "2001" "19:54:32" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "43" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1612 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2L0tNd05688 for starship-design-outgoing; Tue, 20 Mar 2001 16:55:23 -0800 (PST) Received: from imo-r11.mx.aol.com (imo-r11.mx.aol.com [152.163.225.65]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2L0tLC05665 for ; Tue, 20 Mar 2001 16:55:21 -0800 (PST) Received: from KellySt@aol.com by imo-r11.mx.aol.com (mail_out_v29.5.) id z.48.131913c2 (3315) for ; Tue, 20 Mar 2001 19:54:32 -0500 (EST) Message-ID: <48.131913c2.27e955c8@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Tue, 20 Mar 2001 19:54:32 EST In a message dated 3/18/01 9:29:35 PM, bfranchuk@jetnet.ab.ca writes: >KellySt@aol.com wrote: >>> I was getting significantly better speed numbers. More importantly >a mulit >> generation ship is a collosal waste. It requires a vastly larger, heavier, >> more complicated ship. So much so, that the same propulsion gear could >get >> you there in a fraction of the time. Hence a small craft that would >get >> there in years, would be easier to do then one that would get there in >> decades. > >I favor the slower ships because I can't see a practical high speed drive. Same drives work about as well for a small fast ship, or a big slow ship. I was figuring up to 40% c for Fuel sail. >> Also trips that take generations are assured to get their AFTER ships >sent >> out decades after it left. Assuming anyone would bother to send them. > >That is based on the premise a FAST drive is possible. If you can get a multigeneratin ship out at any non-laughable speed - you can get a small short duratin ship up to far faster speeds. >Lets face it >any interstellar travel will require pushing all known technology >to the limit, and it is hard to say exactly what will be possible in the >future because factors can change suddenly. I think several designs >need to be studied. For example >suspension of life that is not possible now >could be possible in the future with the study of DNA and other biological >processes. This could favor slower ship for bulk transport and a high >speed craft for living material. >Ben. For what purpose? The risk goes up tremendosly, but adds little benifit. From VM Wed Mar 21 10:06:25 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1965" "Wednesday" "21" "March" "2001" "14:20:31" "+0100" "Zenon Kulpa" "zkulpa@ippt.gov.pl" nil "45" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1965 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2LDNJo10506 for starship-design-outgoing; Wed, 21 Mar 2001 05:23:19 -0800 (PST) Received: from ippt.gov.pl (zmit1.ippt.gov.pl [148.81.53.8]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2LDNCC10489 for ; Wed, 21 Mar 2001 05:23:17 -0800 (PST) Received: (from zkulpa@localhost) by ippt.gov.pl (8.8.5/8.7.3-zmit) id OAA06775 for starship-design@lists.uoregon.edu; Wed, 21 Mar 2001 14:20:31 +0100 (MET) Message-Id: <200103211320.OAA06775@ippt.gov.pl> Precedence: bulk Reply-To: Zenon Kulpa From: Zenon Kulpa Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Wed, 21 Mar 2001 14:20:31 +0100 (MET) > From owner-starship-design@lists.uoregon.edu Wed Mar 21 02:01:19 2001 > From: KellySt@aol.com > > [...] > >> I can't see how this wouldn't be a trivial problem? Your not talking > >> a high lateral movement, or any delta-V of the two stars. > >> On the scale of the galaxy the two stars are right on top > >> of one another. (A couple light years > >> out of a 30-40 THOUSAND light year orbital radius.) > >> > >For a starship what is important is not the _relative_ change > >of the star position with respect to its distance from the center > >of the Galaxy, but _absolute_ change of its position > >(in light years, say). If the star moves a light year with respect > >to the aim of the starship, the starship must simply travel > >this additional light year (laterally, say) in order to catch it, > >no matter how far (or near) the center of the Galaxy is. > > Relative movement is related to the degree of difference of the orbit. In > this case the fractinal difference would be trivial. As long as the two > stars don't move relative to one another - effectivly they can be treated > as unmoving for nav purposes. > Fractional - yes. But absolute - not necessarily. If the Sun and the star are at different orbit, they do move relative to each other - withe speeds often in tens of km per sec. That may build to notrivial distances during years of travel - not to mention inaccuracies in our measurements of relative speed, distance, etc. > >[...] > >> Tacking, or otherwise manuvering into the path of the beam > >> is nessisary. If you fly out of the beam you'll need > >> secoundary motors to manuver back into the beam. > >> You'll need manuvering engines anyway for in systems work. > >> > >Notice however, that the lateral movement of the beam due to > >any jitter od the beaming antenna will be rather rapid - in fact, > >it may easily exceed the speed of light! > > So don't jitter. > Easier said than done. -- Zenon From VM Thu Mar 22 10:08:28 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2283" "Wednesday" "21" "March" "2001" "21:09:43" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "54" "Re: starship-design: Massively Distributed Computing for SETI" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 2283 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2M29sV18051 for starship-design-outgoing; Wed, 21 Mar 2001 18:09:54 -0800 (PST) Received: from imo-m05.mx.aol.com (imo-m05.mx.aol.com [64.12.136.8]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2M29rC18030 for ; Wed, 21 Mar 2001 18:09:53 -0800 (PST) Received: from KellySt@aol.com by imo-m05.mx.aol.com (mail_out_v29.5.) id z.46.124ad59c (1882) for ; Wed, 21 Mar 2001 21:09:44 -0500 (EST) Message-ID: <46.124ad59c.27eab8e7@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: Massively Distributed Computing for SETI Date: Wed, 21 Mar 2001 21:09:43 EST In a message dated 3/21/01 7:24:49 AM, zkulpa@ippt.gov.pl writes: >> >> I can't see how this wouldn't be a trivial problem? Your not talking >> >> a high lateral movement, or any delta-V of the two stars. >> >> On the scale of the galaxy the two stars are right on top >> >> of one another. (A couple light years >> >> out of a 30-40 THOUSAND light year orbital radius.) >> >> >> >For a starship what is important is not the _relative_ change >> >of the star position with respect to its distance from the center >> >of the Galaxy, but _absolute_ change of its position >> >(in light years, say). If the star moves a light year with respect >> >to the aim of the starship, the starship must simply travel >> >this additional light year (laterally, say) in order to catch it, >> >no matter how far (or near) the center of the Galaxy is. >> >> Relative movement is related to the degree of difference of the orbit. >In >> this case the fractinal difference would be trivial. As long as the >two >> stars don't move relative to one another - effectivly they can be treated > >> as unmoving for nav purposes. >> >Fractional - yes. But absolute - not necessarily. >If the Sun and the star are at different orbit, they do move >relative to each other - withe speeds often in tens of km per sec. >That may build to notrivial distances during years of travel - >not to mention inaccuracies in our measurements of relative speed, >distance, etc. 10 km/s is about 310,000,000 km per year. About 16 light minuttes, or 2 au, or Earth to Mars on a good day. That is completly trivial to a starship! A hundred times that is still completly trivial. >> >[...] >> >> Tacking, or otherwise manuvering into the path of the beam >> >> is nessisary. If you fly out of the beam you'll need >> >> secoundary motors to manuver back into the beam. >> >> You'll need manuvering engines anyway for in systems work. >> >> >> >Notice however, that the lateral movement of the beam due to >> >any jitter od the beaming antenna will be rather rapid - in fact, >> >it may easily exceed the speed of light! >> >> So don't jitter. >> >Easier said than done. We do that on big scopes, and besides with phased arrays over thousands to tens of millions of miles, its handelable. From VM Thu Mar 22 13:48:19 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["3057" "Thursday" "22" "March" "2001" "15:41:31" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "52" "starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 3057 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2MLb0411213 for starship-design-outgoing; Thu, 22 Mar 2001 13:37:00 -0800 (PST) Received: from mail1.mco.bellsouth.net (mail1.mco.bellsouth.net [205.152.111.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2MLawC11205 for ; Thu, 22 Mar 2001 13:36:58 -0800 (PST) Received: from nless (adsl-21-216-37.msy.bellsouth.net [66.21.216.37]) by mail1.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id QAA06011 for ; Thu, 22 Mar 2001 16:36:49 -0500 (EST) Message-ID: <001001c0b318$e00fe920$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: starship-design: Cryogenic Suspension Date: Thu, 22 Mar 2001 15:41:31 -0600 Cryogenic Suspended Animation I've been familiar with this science fiction theme since my childhood. Always, I've been a bit dubious about it, as a personal reaction as well as technically. Having since learned the fundamental drawback to reviving a frozen human is almost intractable, I shelved the concept. But it has been recently mentioned here, in a casual throwaway line, and I did once come up with a potential approach to this problem. Taken from the shelf and lightly dusted off, here it is. Ice crystals slowly forming in blood and tissue have a characteristic size which is larger than the dimensions of cells. That's the problem. Freezing tissue ruptures cell membranes, and that spells dead. OK, but some small creatures, mouse size, can be frozen and revived. Protoplasm is water-based, but has solutes and suspensions which disorder the ice crystals so that most individual cells come out viable, and normal body processes can then replace the minority of destroyed cells in a small organism which has been successfully thawed. Large creatures, however, will not freeze as fast as small ones, for their body bulk is thermally insulating. Fast freezing occurs near the outer surface, so skin and outer regions sustain little damage, but internal organs retain heat, and suffer a slow freezing process which allows growth of larger ice crystals, which spells dead. Obviously body passages, the lungs and digestive tract, are amenable to coolant access to speed freezing, but large organs are still left vulnerable. Among our favorite parts, the central nervous system is protected within bone chambers, still left out of the cold. To use our circulatory system to spread coolant as a temporary replacement for our blood seems far too iffy. My proposal would involve transfixing the entire body rapidly with fine platinum needles, which are heat pipes containing liquid helium as their working fluid. The object of this macabre "iron maiden" treatment is to chill all parts of the body below freezing in less than a second. This should allow large creatures, such as ourselves, to recover on thawing as well as small animals can. Supplementary measures, such as antifreeze proteins added to the blood to reduce ice crystal size, are also called for. This sounds freaky for sure, to allow oneself to be rapidly pierced by jillions of needles, but it could be a key to survival. The subject would of course be unconscious for this ordeal. Later, when thawed and revived to consciousness, it would hurt. Big deal, death hurts worse. Fine needles actually cause little tissue damage, and in this case the body has no time for a histamine response or other trauma. The tiny leaks of fluids would be largely repaired in the thawing process, and nearly healed before the subject regains consciousness. It's just a thought. People here know I don't go for slow starship journeys, but a technique like this would be good to have around anyway. There might be all sorts of reasons for somebody to decide they didn't want to die. Johnny Thunderbird From VM Thu Mar 22 14:28:59 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["3631" "Thursday" "22" "March" "2001" "14:08:17" "-0800" "N. Lindberg" "nlindber@u.washington.edu" nil "67" "Re: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 3631 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2MM8KX26197 for starship-design-outgoing; Thu, 22 Mar 2001 14:08:20 -0800 (PST) Received: from jason05.u.washington.edu (root@jason05.u.washington.edu [140.142.8.54]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2MM8JC26178 for ; Thu, 22 Mar 2001 14:08:19 -0800 (PST) Received: from dante59.u.washington.edu (nlindber@dante59.u.washington.edu [140.142.15.109]) by jason05.u.washington.edu (8.11.2+UW01.01/8.11.2+UW01.03) with ESMTP id f2MM8Hu28242; Thu, 22 Mar 2001 14:08:17 -0800 Received: from localhost (nlindber@localhost) by dante59.u.washington.edu (8.11.2+UW01.01/8.11.2+UW01.03) with ESMTP id f2MM8HO35896; Thu, 22 Mar 2001 14:08:17 -0800 In-Reply-To: <001001c0b318$e00fe920$0a0a0a0a@nless> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Precedence: bulk Reply-To: "N. Lindberg" From: "N. Lindberg" Sender: owner-starship-design@lists.uoregon.edu To: bugzapper cc: Starship Design List Subject: Re: starship-design: Cryogenic Suspension Date: Thu, 22 Mar 2001 14:08:17 -0800 (PST) This is a really novel (afaik) and intruiging idea. How are you going to get at body parts protected by bone, especially the brain and spinal cord? Also, how are you going to keep the needles from bending as they go in real fast? If they bend they either cut through flesh or break off. Anyway, i think this is an idea worthy of discussion. I think it beats the heck out of lopping someones head off and dunking it in LN2. Nels On Thu, 22 Mar 2001, bugzapper wrote: > Cryogenic Suspended Animation > > I've been familiar with this science fiction theme since my childhood. > Always, I've been a bit dubious about it, as a personal reaction as well as > technically. Having since learned the fundamental drawback to reviving a > frozen human is almost intractable, I shelved the concept. But it has been > recently mentioned here, in a casual throwaway line, and I did once come up > with a potential approach to this problem. Taken from the shelf and lightly > dusted off, here it is. > > Ice crystals slowly forming in blood and tissue have a characteristic size > which is larger than the dimensions of cells. That's the problem. Freezing > tissue ruptures cell membranes, and that spells dead. OK, but some small > creatures, mouse size, can be frozen and revived. Protoplasm is water-based, > but has solutes and suspensions which disorder the ice crystals so that most > individual cells come out viable, and normal body processes can then replace > the minority of destroyed cells in a small organism which has been > successfully thawed. > > Large creatures, however, will not freeze as fast as small ones, for their > body bulk is thermally insulating. Fast freezing occurs near the outer > surface, so skin and outer regions sustain little damage, but internal > organs retain heat, and suffer a slow freezing process which allows growth > of larger ice crystals, which spells dead. Obviously body passages, the > lungs and digestive tract, are amenable to coolant access to speed freezing, > but large organs are still left vulnerable. Among our favorite parts, the > central nervous system is protected within bone chambers, still left out of > the cold. To use our circulatory system to spread coolant as a temporary > replacement for our blood seems far too iffy. > > My proposal would involve transfixing the entire body rapidly with fine > platinum needles, which are heat pipes containing liquid helium as their > working fluid. The object of this macabre "iron maiden" treatment is to > chill all parts of the body below freezing in less than a second. This > should allow large creatures, such as ourselves, to recover on thawing as > well as small animals can. Supplementary measures, such as antifreeze > proteins added to the blood to reduce ice crystal size, are also called for. > > This sounds freaky for sure, to allow oneself to be rapidly pierced by > jillions of needles, but it could be a key to survival. The subject would of > course be unconscious for this ordeal. Later, when thawed and revived to > consciousness, it would hurt. Big deal, death hurts worse. Fine needles > actually cause little tissue damage, and in this case the body has no time > for a histamine response or other trauma. The tiny leaks of fluids would be > largely repaired in the thawing process, and nearly healed before the > subject regains consciousness. > > It's just a thought. People here know I don't go for slow starship journeys, > but a technique like this would be good to have around anyway. There might > be all sorts of reasons for somebody to decide they didn't want to die. > > Johnny Thunderbird > > From VM Mon Mar 26 10:19:54 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1232" "Thursday" "22" "March" "2001" "08:40:00" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "26" "Re: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil "starship-design: Cryogenic Suspension" nil nil nil] nil) Content-Length: 1232 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2N3BmW29552 for starship-design-outgoing; Thu, 22 Mar 2001 19:11:48 -0800 (PST) Received: from main.jetnet.ab.ca (root@jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2N3BfC29528 for ; Thu, 22 Mar 2001 19:11:46 -0800 (PST) Received: from jetnet.ab.ca (dialin46.jetnet.ab.ca [207.153.6.46]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id UAA27259 for ; Thu, 22 Mar 2001 20:11:27 -0700 (MST) Message-ID: <3ABA1CD0.45C6C4DE@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: <001001c0b318$e00fe920$0a0a0a0a@nless> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu CC: Starship Design List Subject: Re: starship-design: Cryogenic Suspension Date: Thu, 22 Mar 2001 08:40:00 -0700 > Ice crystals slowly forming in blood and tissue have a characteristic size > which is larger than the dimensions of cells. That's the problem. Freezing > tissue ruptures cell membranes, and that spells dead. OK, but some small > creatures, mouse size, can be frozen and revived. Protoplasm is water-based, > but has solutes and suspensions which disorder the ice crystals so that most > individual cells come out viable, and normal body processes can then replace > the minority of destroyed cells in a small organism which has been > successfully thawed. >> > Johnny Thunderbird Why is freezing needed? You have three options 1) Slow down the body by keeping it just above 32F. See chipmunk dan or hibernating harry. 2)Clean and reset the cells to a early time every few years. This is at the DNA level that would sweep through the body and repair aging DAMAGE and clean up the body. 3) Create longer living people (test tube baby style) Ben. PS. Send a very slow moving craft to the stars and have the slime evolve into people when you get there.:) -- "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk From VM Mon Mar 26 10:19:54 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["4054" "Friday" "23" "March" "2001" "19:27:09" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "77" "Re: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil "starship-design: Cryogenic Suspension" nil nil nil] nil) Content-Length: 4054 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2O1MLF03894 for starship-design-outgoing; Fri, 23 Mar 2001 17:22:21 -0800 (PST) Received: from mail1.mco.bellsouth.net (mail1.mco.bellsouth.net [205.152.111.13]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2O1MJC03889 for ; Fri, 23 Mar 2001 17:22:20 -0800 (PST) Received: from nless (adsl-20-123-64.msy.bellsouth.net [66.20.123.64]) by mail1.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id UAA05074 for ; Fri, 23 Mar 2001 20:22:15 -0500 (EST) Message-ID: <002c01c0b401$8f698c80$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MIMEOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Cryogenic Suspension Date: Fri, 23 Mar 2001 19:27:09 -0600 Nels Lindberg wrote: This is a really novel (afaik) and intruiging idea. How are you going to get at body parts protected by bone, especially the brain and spinal cord? Also, how are you going to keep the needles from bending as they go in real fast? If they bend they either cut through flesh or break off. Anyway, i think this is an idea worthy of discussion. I think it beats the heck out of lopping someones head off and dunking it in LN2. Nels ------ Appreciate your consideration, Nels. Your pointed questions show you're thinking seriously on this. We might not want to get too "clinical" here, or somebody might get turned off. (Please, nobody ask me a question about the eyeballs!) First we should prove the concept, then develop the technique. Let me say I chose platinum because organisms have an absolutely zero reaction to it, making it completely inert physiologically. This, though, is overspecified; tungsten or stainless steel would work equally well. Platinum, though, in spite of being a noble metal, is not at all weak. Whatever the material, your basic question about the bone penetration applies the same way. I would expect the answer to involve forcible insertion of the needle into the bone. I have flashbacks to bone marrow biopsies conducted with needles on my hipbones, as part of my treatment for mantle cell lymphoma. The hip is the largest, and I think the hardest bone. The doctor had no trouble getting a steel needle into it, though some force was required. Most distressing, I can tell you. ------- Ben Franchuk wrote: Why is freezing needed? You have three options 1) Slow down the body by keeping it just above 32F. See chipmunk dan or hibernating harry. 2)Clean and reset the cells to a early time every few years. This is at the DNA level that would sweep through the body and repair aging DAMAGE and clean up the body. 3) Create longer living people (test tube baby style) Ben. PS. Send a very slow moving craft to the stars and have the slime evolve into people when you get there.:) ------- Thanks for pointing out these options. Freezing is only needed to keep people from dying, whether from lapse of time, or from shorter term factors. Hibernation I would expect to require constant maintenance, at a level of intensive care comparable to that needed by a coma patient. Respiration and circulation must be maintained. If nutrient levels in the blood fall, the subject must be revived to eat. Since body cells are active, the microorganisms of the body certainly are. Hibernation in nature is a ninety-day phenomonon, at a constant physiological cost. It does not stop the metabolism, nor prevent aging. I don't see much advantage of this over the active state, at least enough to compensate being so vulnerable. Should we find out what hibernation is, and how to induce it in humans, and how to extend it for years, and how to ward off starvation, and how to maintain the bodily tone, and how to prevent biodegradation of the tissues consumed by microbes, I think it would still be too risky. Rejuvenation is a very interesting concept. An organism's cells are limited to about fifty generations of cell division. Theory among biologists points toward the progressive shortening of the telomeres of chromosomes, the non-coding repetitive DNA sequences at their exposed ends, as the cause of this limitation. Recent work http://www.sciencedaily.com/releases/1998/01/980119073637.htm indicates some possibilities in this regard. Life extension by genetic treatment now glimmers as a remote posibility on the far horizon. I don't feel, however, that you and I should place this among our immediate concerns. What I'm saying, is my proposal is immediate and concrete. If you can spare me a dozen hogs, a tank of liquid helium, and 2748 platinum needles, I can show you if it works or not. Experiment can provide a decisive answer to any related questions of theory. To consider an alternative to this method, we need it to be a comparable plan, at the same level of specificity. Johnny Thunderbird From VM Mon Mar 26 10:19:54 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2605" "Thursday" "22" "March" "2001" "15:08:31" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "49" "Re: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil "starship-design: Cryogenic Suspension" nil nil nil] nil) Content-Length: 2605 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2O1eP809786 for starship-design-outgoing; Fri, 23 Mar 2001 17:40:25 -0800 (PST) Received: from main.jetnet.ab.ca (root@jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2O1eOC09776 for ; Fri, 23 Mar 2001 17:40:24 -0800 (PST) Received: from jetnet.ab.ca (dialin59.jetnet.ab.ca [207.153.6.59]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id SAA16365 for ; Fri, 23 Mar 2001 18:40:01 -0700 (MST) Message-ID: <3ABA77DF.462DA699@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: <002c01c0b401$8f698c80$0a0a0a0a@nless> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu CC: Starship Design List Subject: Re: starship-design: Cryogenic Suspension Date: Thu, 22 Mar 2001 15:08:31 -0700 bugzapper wrote: > Thanks for pointing out these options. Freezing is only needed to keep > people from dying, whether from lapse of time, or from shorter term factors. > Hibernation I would expect to require constant maintenance, at a level of > intensive care comparable to that needed by a coma patient. Does a bear need a hospital every winter. > Respiration and > circulation must be maintained. If nutrient levels in the blood fall, the > subject must be revived to eat. Since body cells are active, the > microorganisms of the body certainly are. Hibernation in nature is a > ninety-day phenomonon, at a constant physiological cost. It does not stop > the metabolism, nor prevent aging. I don't see much advantage of this over > the active state, at least enough to compensate being so vulnerable. Should > we find out what hibernation is, and how to induce it in humans, and how to > extend it for years, and how to ward off starvation, and how to maintain the > bodily tone, and how to prevent biodegradation of the tissues consumed by > microbes, I think it would still be too risky. But who says it has to be a 60 or 90 days at a time.A two week sleep followed be one week on may be good starting point for inter-planetary trips.I see hibernation as a start for low temperature sleep around +4C. > > Rejuvenation is a very interesting concept. An organism's cells are limited > to about fifty generations of cell division. Theory among biologists points > toward the progressive shortening of the telomeres of chromosomes, the > non-coding repetitive DNA sequences at their exposed ends, as the cause of > this limitation. Recent work > http://www.sciencedaily.com/releases/1998/01/980119073637.htm > indicates some possibilities in this regard. Life extension by genetic > treatment now glimmers as a remote posibility on the far horizon. I don't > feel, however, that you and I should place this among our immediate > concerns. > > What I'm saying, is my proposal is immediate and concrete. If you can spare > me a dozen hogs, a tank of liquid helium, and 2748 platinum needles, I can > show you if it works or not. Experiment can provide a decisive answer to any > related questions of theory. To consider an alternative to this method, we > need it to be a comparable plan, at the same level of specificity. why all that? use hamsters and steel needles. Liquid nitrogen is cheap. Ben. > Johnny Thunderbird -- "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk From VM Mon Mar 26 10:19:54 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["473" "Friday" "23" "March" "2001" "20:29:50" "-0600" "Kyle R. Mcallister" "stk@sunherald.infi.net" nil "11" "Re: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil "starship-design: Cryogenic Suspension" nil nil nil] nil) Content-Length: 473 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2O2dHI26062 for starship-design-outgoing; Fri, 23 Mar 2001 18:39:17 -0800 (PST) Received: from granger.mail.mindspring.net (granger.mail.mindspring.net [207.69.200.148]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2O2dEC26051 for ; Fri, 23 Mar 2001 18:39:15 -0800 (PST) Received: from oemcomputer.sunherald.infi.net (ip87.pascagoula2.ms.pub-ip.psi.net [38.30.116.87]) by granger.mail.mindspring.net (8.9.3/8.8.5) with ESMTP id VAA03357 for ; Fri, 23 Mar 2001 21:39:12 -0500 (EST) Message-Id: <5.0.0.25.0.20010323202835.01fda980@pop.infi-net.mindspring.com> X-Sender: stk@pop.infi-net.mindspring.com X-Mailer: QUALCOMM Windows Eudora Version 5.0 In-Reply-To: <001001c0b318$e00fe920$0a0a0a0a@nless> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed Precedence: bulk Reply-To: "Kyle R. Mcallister" From: "Kyle R. Mcallister" Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: Cryogenic Suspension Date: Fri, 23 Mar 2001 20:29:50 -0600 At 03:41 PM 3/22/01 -0600, you wrote: >Later, when thawed and revived to >consciousness, it would hurt. Big deal, death hurts worse. Fine needles >actually cause little tissue damage, and in this case the body has no time >for a histamine response or other trauma. The tiny leaks of fluids would be >largely repaired in the thawing process, and nearly healed before the >subject regains consciousness. How would the subject be thawed out? At what rate of thawing? --Kyle From VM Mon Mar 26 10:19:54 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["976" "Friday" "23" "March" "2001" "22:25:05" "-0500" "pk" "thida@videotron.ca" nil "24" "RE: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil "starship-design: Cryogenic Suspension" nil nil nil] nil) Content-Length: 976 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2O3Pm906723 for starship-design-outgoing; Fri, 23 Mar 2001 19:25:48 -0800 (PST) Received: from VL-MS-MR002.sc1.videotron.ca (relais.videotron.ca [24.201.245.36]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2O3PkC06716 for ; Fri, 23 Mar 2001 19:25:46 -0800 (PST) Received: from ordi1 ([24.200.17.121]) by VL-MS-MR002.sc1.videotron.ca (Netscape Messaging Server 4.15) with SMTP id GAOMRS04.GIM; Fri, 23 Mar 2001 22:23:52 -0500 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) X-MIMEOLE: Produced By Microsoft MimeOLE V5.00.2314.1300 In-Reply-To: <5.0.0.25.0.20010323202835.01fda980@pop.infi-net.mindspring.com> Importance: Normal Precedence: bulk Reply-To: "pk" From: "pk" Sender: owner-starship-design@lists.uoregon.edu To: "Kyle R. Mcallister" , Subject: RE: starship-design: Cryogenic Suspension Date: Fri, 23 Mar 2001 22:25:05 -0500 > -----Original Message----- > From: owner-starship-design@lists.uoregon.edu > [mailto:owner-starship-design@lists.uoregon.edu]On Behalf Of Kyle R. > Mcallister > Sent: 23 mars, 2001 21:30 > To: starship-design@lists.uoregon.edu > Subject: Re: starship-design: Cryogenic Suspension > > > At 03:41 PM 3/22/01 -0600, you wrote: > >Later, when thawed and revived to > >consciousness, it would hurt. Big deal, death hurts worse. Fine needles > >actually cause little tissue damage, and in this case the body > has no time > >for a histamine response or other trauma. The tiny leaks of > fluids would be > >largely repaired in the thawing process, and nearly healed before the > >subject regains consciousness. > > How would the subject be thawed out? At what rate of thawing? Well, i'd guess as fast as possible 8) (though, while taking care not to cause tissue damage bc of the temperature difference) Injecting hot air/water into the previously used fine needle could work, no? From VM Mon Mar 26 10:19:54 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1280" "Saturday" "24" "March" "2001" "00:03:49" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "57" "starship-design: Re: Lunar Institute collaboration with TransOrbital, Inc." "^From:" nil nil "3" nil "starship-design: Re: Lunar Institute collaboration with TransOrbital, Inc." nil nil nil] nil) Content-Length: 1280 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2O544O28851 for starship-design-outgoing; Fri, 23 Mar 2001 21:04:04 -0800 (PST) Received: from imo-r18.mx.aol.com (imo-r18.mx.aol.com [152.163.225.72]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2O543C28846 for ; Fri, 23 Mar 2001 21:04:03 -0800 (PST) Received: from KellySt@aol.com by imo-r18.mx.aol.com (mail_out_v29.5.) id z.f4.8517039 (4387); Sat, 24 Mar 2001 00:03:50 -0500 (EST) Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: PBlase@aol.com, starship-design@lists.uoregon.edu Subject: starship-design: Re: Lunar Institute collaboration with TransOrbital, Inc. Date: Sat, 24 Mar 2001 00:03:49 EST In a message dated 3/23/01 1:53:47 PM, PBlase writes: >Dear m.h. Starks, > > > >TransOrbital, Inc. is currently designing >its 2001 Trailblazer lunar imaging spacecraft - intended to be launched >at the end of this year as the first commercial lunar mission. We would >like to invite the Institute to participate in the 2001 Trailblazer mission. > > > > >Primarily, as part of a consumer product associated with the mission, we >will be including a computer CD containing information about the mission >and the Moon. Given the Institute's interest in the subject, I believe >that a partnership in developing material for the CD would be mutually >beneficial. > > > >If you are not the person responsible, I would greatly appreciate it if >you could direct me to the proper contact. Thank you. > > > >Sincerely > >W. Paul Blase > >TransOrbital, Inc. > >6430 The Parkway > >Alexandria, VA 22310 > >http://www.transorbital.net > >pblase@transorbital.net > >703.960.5953 Hi Paul, I guess I'm as good a point of contact as anyone. The group hasn't been very active lately, but I think we'ld be happy to participate. What did you have in mind? Kelly Starks 319-396-1681 262-705-5972 cell phone 2415 Oxford Ln. N.W. #4 Cedar Rapids IA 52405 From VM Mon Mar 26 10:19:54 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2302" "Sunday" "25" "March" "2001" "08:08:31" "-0600" "L. Parker" "lparker@cacaphony.net" nil "89" "starship-design: Proper Motion" "^From:" nil nil "3" nil "starship-design: Proper Motion" nil nil nil] nil) Content-Length: 2302 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2PErEI20946 for starship-design-outgoing; Sun, 25 Mar 2001 06:53:14 -0800 (PST) Received: from traffic.gnt.net (root@gnt.com [204.49.53.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2PErDC20941 for ; Sun, 25 Mar 2001 06:53:13 -0800 (PST) Received: from broadsword (p456.gnt.com [204.49.91.72]) by traffic.gnt.net (8.9.1a/8.9.0) with SMTP id IAA23934 for ; Sun, 25 Mar 2001 08:53:10 -0600 Message-ID: <004b01c0b53b$26040730$0100a8c0@broadsword> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_004C_01C0B508.DB699730" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.2416 (9.0.2910.0) Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6700 Precedence: bulk Reply-To: "L. Parker" From: "L. Parker" Sender: owner-starship-design@lists.uoregon.edu To: "Starship-Design \(E-mail\)" Subject: starship-design: Proper Motion Date: Sun, 25 Mar 2001 08:08:31 -0600 This is a multi-part message in MIME format. ------=_NextPart_000_004C_01C0B508.DB699730 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit The following objects are the ten highest proper motion stars contained in the Hipparcos Catalogue: Name of star or region RA, Dec Barnard's star 269.4, 4.6 Kapteyn's star 77.8, -45.0 Groombridge 1830 178.2, 37.7 Lacaille 9352 346.4, -35.8 CD -37 15492 1.3, -37.3 HIP 67593 207.7, 23.7 61 Cygni A & 61 Cygni B 316.7, 38.7 Lalande 21185 165.8, 35.9 epsilon Indi 330.8, -56.8 Notice that many of these stars are also the closest stars to Earth. Which of course, is too be expected. Lee ------=_NextPart_000_004C_01C0B508.DB699730 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

The following objects are the ten highest proper motion stars = contained in=20 the Hipparcos Catalogue:

 

Name of star or region RA, Dec
Barnard's star 269.4, 4.6
Kapteyn's star 77.8, -45.0
Groombridge 1830 178.2, 37.7
Lacaille 9352 346.4, -35.8
CD -37 15492 1.3, -37.3
HIP 67593 207.7, 23.7
61 Cygni A & 61 Cygni B 316.7, 38.7
Lalande 21185 165.8, 35.9
epsilon Indi 330.8, -56.8
 
 
Notice that many of these stars are also the = closest=20 stars to Earth. Which of course, is too be expected.
 
Lee
------=_NextPart_000_004C_01C0B508.DB699730-- From VM Mon Mar 26 19:33:54 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["815" "Monday" "26" "March" "2001" "22:14:05" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "22" "starship-design: Re: Lunar Institute collaboration with TransOrbital, Inc." "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 815 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2R3EZR03873 for starship-design-outgoing; Mon, 26 Mar 2001 19:14:35 -0800 (PST) Received: from imo-r19.mx.aol.com (imo-r19.mx.aol.com [152.163.225.73]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2R3EYC03867 for ; Mon, 26 Mar 2001 19:14:34 -0800 (PST) Received: from KellySt@aol.com by imo-r19.mx.aol.com (mail_out_v29.5.) id z.a8.130d7143 (18407); Mon, 26 Mar 2001 22:14:06 -0500 (EST) Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: PBlase@aol.com, starship-design@lists.uoregon.edu Subject: starship-design: Re: Lunar Institute collaboration with TransOrbital, Inc. Date: Mon, 26 Mar 2001 22:14:05 EST In a message dated 3/25/01 8:23:44 PM, PBlase writes: ><< What did you have in mind? > >> > >Basically, as part of the CD we'd like to include a collection of lunar >data: images, an atlas, history, mythology - whatever could be put together, >preferably out of public-domain material, into an HTML (read on anything) >document. We have some material that we'd like to put on there, but not >enough to fill a whole CD. I can master the disk, but we're a little short-handed, >and busy trying to design the spacecraft, and I thought that a group like >yours would like to take it on. We'd need a professional product, terms >to be negotiated. > >Paul Blase Well, we're more of an amateur club, and from the site you can judge our quality (and see if there is anything there that interests you). Kelly Starks From VM Tue Mar 27 10:21:24 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["2907" "Tuesday" "27" "March" "2001" "10:18:15" "-0600" "bugzapper" "bugzappr@bellsouth.net" nil "80" "Re: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 2907 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2RGDWh07421 for starship-design-outgoing; Tue, 27 Mar 2001 08:13:32 -0800 (PST) Received: from mail2.mco.bellsouth.net ([205.152.111.14]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2RGDVo07416 for ; Tue, 27 Mar 2001 08:13:31 -0800 (PST) Received: from nless (adsl-21-217-186.msy.bellsouth.net [66.21.217.186]) by mail2.mco.bellsouth.net (3.3.5alt/0.75.2) with SMTP id LAA15669 for ; Tue, 27 Mar 2001 11:03:21 -0500 (EST) Message-ID: <002601c0b6d9$8cbf9c60$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 Precedence: bulk Reply-To: "bugzapper" From: "bugzapper" Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Cryogenic Suspension Date: Tue, 27 Mar 2001 10:18:15 -0600 Oops: sent this wrong the other day, didn't get to the list. Ben says: Does a bear need a hospital every winter. ------- You're right, but... Bears are natural hibernators. We don't know how or why it happens. We just don't know what this state of being is. I saw a paleontologist suggest on TV that some polar dinosaurs may have hibernated. ------- Again from Ben: But who says it has to be a 60 or 90 days at a time.A two week sleep followed be one week on may be good starting point for inter-planetary trips.I see hibernation as a start for low temperature sleep around +4C. ------- Might be. I personally get a creepy crawly feeling about hibernation, that doesn't come when I think about deep freeze. ------- Ben again: why all that? use hamsters and steel needles. Liquid nitrogen is cheap. Ben. ------- But we already know we can sucessfully freeze, thaw and revive small animals, with no special preparations. Like you say, in LN2. The technical hurdle is in bigger beasts, say fox size and larger. Steel needles and LN2 are fine, and experiments with dogs would test the concept, but with hamsters the concept would not be tested. But we would have to test an animal of at least human mass, before it could be concientiously applied to a human. ------- Kyle quotes me, and asks: >Later, when thawed and revived to >consciousness, it would hurt. Big deal, death hurts worse. Fine needles >actually cause little tissue damage, and in this case the body has no time >for a histamine response or other trauma. The tiny leaks of fluids would be >largely repaired in the thawing process, and nearly healed before the >subject regains consciousness. How would the subject be thawed out? At what rate of thawing? --Kyle ------ so pk sez: > > How would the subject be thawed out? At what rate of thawing? > Well, i'd guess as fast as possible 8) > (though, while taking care not to cause tissue damage bc of the temperature > difference) > Injecting hot air/water into the previously used fine needle could work, no? Hey, folks, I don't know. I can tell you what I had in mind, though. I had in mind, that the heat pipe needles would be withdrawn right after inducing freezing. Then for the thawing, what I had in mind was low intensity microwave heating, which would be "as fast as possible". I don't know why it would have to be done quickly, but my gut feeling goes along with pk here, to get it over with. Nuke that corpsicle. Deep freeze is a very secure, snuggly state. Nothing happens. I'm sure that radiation damage can still happen to DNA, but such damage is isolated and doesn't spread by replication. Chromosome repair on thawing can take care of this primary damage, before it has a chance to become carcinogenisis. If freezing can be proved out, using heat pipe needles or not, it can be a relatively simple way to save lives which are otherwise lost. Johnny Thunderbird From VM Tue Mar 27 10:21:24 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["511" "Tuesday" "27" "March" "2001" "12:02:06" "-0600" "Gene & James Marlin" "rmarlin@network-one.com" nil "11" "Re: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 511 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2RI6Xm14771 for starship-design-outgoing; Tue, 27 Mar 2001 10:06:33 -0800 (PST) Received: from mail.bignetsouth.net (mail.ayrix.net [64.49.1.26]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2RI6Wo14758 for ; Tue, 27 Mar 2001 10:06:32 -0800 (PST) Received: from y4c7d6 ([64.49.6.102]) by mail.bignetsouth.net (Post.Office MTA v3.5.3 release 223 ID# 0-57710U53000L800S0V35) with SMTP id net for ; Tue, 27 Mar 2001 13:14:02 -0500 Message-ID: <000a01c0b6e8$0e2be700$66063140@y4c7d6> References: <002601c0b6d9$8cbf9c60$0a0a0a0a@nless> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Precedence: bulk Reply-To: rmarlin@network-one.com (Gene & James Marlin) From: rmarlin@network-one.com (Gene & James Marlin) Sender: owner-starship-design@lists.uoregon.edu To: Subject: Re: starship-design: Cryogenic Suspension Date: Tue, 27 Mar 2001 12:02:06 -0600 I cringe at the thought of microwaving a human being, and cringe even more at the freezing. We're thinking about DNA and cancers when we should be thinking about mechanical damage to tissues first. Remember the simple reason why exposure to microwave energy is regulated by the FCC, very slight heating of certain tissues, especially in the eye, causes mechanical damage, particularly cataracts. Freezing those suckers would be disasterous, even if you can re-awaken the cells themselves later. -Gene From VM Tue Mar 27 14:13:31 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["368" "Tuesday" "27" "March" "2001" "14:08:47" "-0800" "Steve VanDevender" "stevev@efn.org" nil "9" "Re: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 368 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2RM8jx13620 for starship-design-outgoing; Tue, 27 Mar 2001 14:08:45 -0800 (PST) Received: from clavin.efn.org (root@clavin.efn.org [206.163.176.10]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2RM8io13589 for ; Tue, 27 Mar 2001 14:08:44 -0800 (PST) Received: from tzadkiel.efn.org (tzadkiel.efn.org [206.163.182.194]) by clavin.efn.org (8.10.1/8.10.1) with ESMTP id f2RM8hG11404 for ; Tue, 27 Mar 2001 14:08:43 -0800 (PST) Received: (from stevev@localhost) by tzadkiel.efn.org (8.10.1/8.10.1) id f2RM8mL15023; Tue, 27 Mar 2001 14:08:48 -0800 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15041.3951.415954.936420@tzadkiel.efn.org> In-Reply-To: <002601c0b6d9$8cbf9c60$0a0a0a0a@nless> References: <002601c0b6d9$8cbf9c60$0a0a0a0a@nless> X-Mailer: VM 6.92 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid Precedence: bulk Reply-To: Steve VanDevender From: Steve VanDevender Sender: owner-starship-design@lists.uoregon.edu To: "Starship Design List" Subject: Re: starship-design: Cryogenic Suspension Date: Tue, 27 Mar 2001 14:08:47 -0800 bugzapper writes: > Bears are natural hibernators. No, bears are estivators. They don't hibernate, they just sleep for a few months. Their body temperature doesn't drop and their heartbeat and breathing don't stop as happens with animals that actually hibernate. If you're going to use an example of an animal that hibernates, use one that really does hibernate. From VM Thu Mar 29 10:18:17 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["380" "Wednesday" "28" "March" "2001" "21:22:03" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "7" "Re: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 380 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2T2MbZ06930 for starship-design-outgoing; Wed, 28 Mar 2001 18:22:37 -0800 (PST) Received: from imo-r13.mx.aol.com (imo-r13.mx.aol.com [152.163.225.67]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2T2Mao06897 for ; Wed, 28 Mar 2001 18:22:36 -0800 (PST) Received: from KellySt@aol.com by imo-r13.mx.aol.com (mail_out_v29.5.) id z.6f.133319b0 (9678) for ; Wed, 28 Mar 2001 21:22:04 -0500 (EST) Message-ID: <6f.133319b0.27f3f64b@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: starship-design@lists.uoregon.edu Subject: Re: starship-design: Cryogenic Suspension Date: Wed, 28 Mar 2001 21:22:03 EST Their is also a new proces called vitrification. In it the person is chilled down to below freezing under presure. With enough presure you can chill someone down to a very low temp without freezing. Suddenly drop the presure at that point, and the fluids freeze so fast it doesn't crystalize. It turns to glass. No ice crystal damage. Cryonics folks are very excited. From VM Thu Mar 29 10:18:17 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["1782" "Wednesday" "28" "March" "2001" "21:21:57" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "43" "starship-design: Fwd: Doomed engineers ;/" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 1782 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2T2MDY06525 for starship-design-outgoing; Wed, 28 Mar 2001 18:22:13 -0800 (PST) Received: from imo-r11.mx.aol.com (imo-r11.mx.aol.com [152.163.225.65]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2T2MBo06501 for ; Wed, 28 Mar 2001 18:22:11 -0800 (PST) Received: from KellySt@aol.com by imo-r11.mx.aol.com (mail_out_v29.5.) id n.2f.1302e2af (9678); Wed, 28 Mar 2001 21:21:58 -0500 (EST) Message-ID: <2f.1302e2af.27f3f645@aol.com> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="part1_2f.1302e2af.27f3f645_boundary" X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: DTaylor648@aol.com, JohnFrance@aol.com, moschleg@erols.com, SFnoirSD@aol.com, starship-design@lists.uoregon.edu, alford@netcom.com, bbbark@surfree.com, jcavelos@mindspring.com, DotarSojat@aol.com, rddesign@rddesigns.com, RICKJ@btio.com, millahnna@yahoo.com, edrataj@earthlink.net, ARobnett@aol.com, alwermter@netzero.net Subject: starship-design: Fwd: Doomed engineers ;/ Date: Wed, 28 Mar 2001 21:21:57 EST --part1_2f.1302e2af.27f3f645_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 3/28/01 11:06:10 AM, kgstarks@collins.rockwell.com writes: >Found this in the process: > http://world.std.com/~jlr/doom/doom_eng.htm > Kelly, you might find this interesting: > > --part1_2f.1302e2af.27f3f645_boundary Content-Type: message/rfc822 Content-Disposition: inline Return-Path: Received: from rly-xc02.mx.aol.com (rly-xc02.mail.aol.com [172.20.105.135]) by air-xc05.mail.aol.com (v77_r1.36) with ESMTP; Wed, 28 Mar 2001 12:06:10 1900 Received: from fw01.collins.rockwell.com (gatekeeper.collins.rockwell.com [205.175.225.1]) by rly-xc02.mx.aol.com (v77_r1.36) with ESMTP; Wed, 28 Mar 2001 12:06:08 -0500 Received: by fw01.collins.rockwell.com; id LAA27774; Wed, 28 Mar 2001 11:06:00 -0600 (CST) From: Received: from nodnsquery(131.198.213.32) by fw01.collins.rockwell.com via smap (V5.5) id xma027189; Wed, 28 Mar 01 11:04:34 -0600 Subject: Doomed engineers ;/ To: ghcotto5@collins.rockwell.com, kellyst@aol.com, sjhootma@collins.rockwell.com, kath2go@yahoo.com, Kryswalker@aol.com, "Michnavich, George" Date: Wed, 28 Mar 2001 11:03:59 -0600 Message-ID: X-MIMETrack: Serialize by Router on CollinsCRSMTP01/CedarRapids/Collins/Rockwell(Release 5.0.6 |December 14, 2000) at 03/28/2001 11:04:35 AM MIME-Version: 1.0 Content-type: text/plain; charset=us-ascii X-Mailer: Unknown (No Version) Found this in the process: http://world.std.com/~jlr/doom/doom_eng.htm Kelly, you might find this interesting: --part1_2f.1302e2af.27f3f645_boundary-- From VM Thu Mar 29 10:18:17 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["590" "Thursday" "29" "March" "2001" "01:37:21" "-0800" "N. Lindberg" "nlindber@u.washington.edu" nil "17" "Re: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 590 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2T9bOk12401 for starship-design-outgoing; Thu, 29 Mar 2001 01:37:24 -0800 (PST) Received: from jason04.u.washington.edu (root@jason04.u.washington.edu [140.142.8.53]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2T9bNo12384 for ; Thu, 29 Mar 2001 01:37:23 -0800 (PST) Received: from dante39.u.washington.edu (nlindber@dante39.u.washington.edu [140.142.15.199]) by jason04.u.washington.edu (8.11.2+UW01.01/8.11.2+UW01.03) with ESMTP id f2T9bMm30454 for ; Thu, 29 Mar 2001 01:37:22 -0800 Received: from localhost (nlindber@localhost) by dante39.u.washington.edu (8.11.2+UW01.01/8.11.2+UW01.03) with ESMTP id f2T9bLS99262 for ; Thu, 29 Mar 2001 01:37:21 -0800 In-Reply-To: <6f.133319b0.27f3f64b@aol.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Precedence: bulk Reply-To: "N. Lindberg" From: "N. Lindberg" Sender: owner-starship-design@lists.uoregon.edu To: starship design Subject: Re: starship-design: Cryogenic Suspension Date: Thu, 29 Mar 2001 01:37:21 -0800 (PST) Does anyone know how far along research has gotten in this area (vitrifying animals). If anyone knows of a good URL, I'd be interested to have it. Nels On Wed, 28 Mar 2001 KellySt@aol.com wrote: > Their is also a new proces called vitrification. In it the person is chilled > down to below freezing under presure. With enough presure you can chill > someone down to a very low temp without freezing. Suddenly drop the presure > at that point, and the fluids freeze so fast it doesn't crystalize. It turns > to glass. No ice crystal damage. > > Cryonics folks are very excited. > From VM Thu Mar 29 19:07:51 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["826" "Thursday" "29" "March" "2001" "22:04:27" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "29" "Re: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 826 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2U34hK11163 for starship-design-outgoing; Thu, 29 Mar 2001 19:04:43 -0800 (PST) Received: from imo-m02.mx.aol.com (imo-m02.mx.aol.com [64.12.136.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2U34go11156 for ; Thu, 29 Mar 2001 19:04:42 -0800 (PST) Received: from KellySt@aol.com by imo-m02.mx.aol.com (mail_out_v29.14.) id d.36.13b4c83c (4562); Thu, 29 Mar 2001 22:04:27 -0500 (EST) Message-ID: <36.13b4c83c.27f551bb@aol.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: nlindber@u.washington.edu, starship-design@lists.uoregon.edu Subject: Re: starship-design: Cryogenic Suspension Date: Thu, 29 Mar 2001 22:04:27 EST I don't know of anything online. I saw it on tv. I know they were doing it on organs, but I'm not sure if they tried lab animals. Kelly In a message dated 3/29/01 3:39:02 AM, nlindber@u.washington.edu writes: > Does anyone know how far along research has gotten in this area >(vitrifying animals). If anyone knows of a good URL, I'd be interested >to >have it. > >Nels > > >On Wed, 28 Mar 2001 KellySt@aol.com wrote: > >> Their is also a new proces called vitrification. In it the person is >chilled >> down to below freezing under presure. With enough presure you can chill >> someone down to a very low temp without freezing. Suddenly drop the >presure >> at that point, and the fluids freeze so fast it doesn't crystalize. >It turns >> to glass. No ice crystal damage. >> >> Cryonics folks are very excited. From VM Thu Mar 29 19:10:35 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["26646" "Thursday" "29" "March" "2001" "22:04:35" "EST" "KellySt@aol.com" "KellySt@aol.com" nil "484" "starship-design: Re: we need your help for our project" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 26646 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2U36Ci11490 for starship-design-outgoing; Thu, 29 Mar 2001 19:06:12 -0800 (PST) Received: from imo-m02.mx.aol.com (imo-m02.mx.aol.com [64.12.136.5]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2U36Ao11485 for ; Thu, 29 Mar 2001 19:06:10 -0800 (PST) Received: from KellySt@aol.com by imo-m02.mx.aol.com (mail_out_v29.14.) id x.3b.12851d3e (4562); Thu, 29 Mar 2001 22:04:35 -0500 (EST) Message-ID: <3b.12851d3e.27f551c3@aol.com> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="part1_3b.12851d3e.27f551c3_boundary" X-Mailer: AOL 5.0 for Mac sub 28 Precedence: bulk Reply-To: KellySt@aol.com From: KellySt@aol.com Sender: owner-starship-design@lists.uoregon.edu To: b_sengur@usa.net, starship-design@lists.uoregon.edu Subject: starship-design: Re: we need your help for our project Date: Thu, 29 Mar 2001 22:04:35 EST --part1_3b.12851d3e.27f551c3_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 3/29/01 4:51:41 AM, b_sengur@usa.net writes: >Dear Sir/Madam, > >Me and some of my friends are researching and preparing project about Lunar >Resources. But we could not find any good informations about LR. Therefore, >we >need some help. if you have good informations, documents, brochures, images >or >links, please try to send us by e-mail or mail. We need your helps certainly. >e.g : what kind of lunar resources are using? and why? > where and how can we produce them? > >e-mail : b_sengur@hotmail.com > b_sengur@usa.net > >mail : Eastern Mediterranean University > Department of Civil Enginnering > Mersin10, Gazimagosa > TURKEY > >Best Regards, > >Gultekin BUYUKSENGUR I'm not sure what exactly your asking for. Asside from the info on the site and sites it links to, I cut these out for you. I hope they help. It cover various space comercialization efforts. Kelly Starks --part1_3b.12851d3e.27f551c3_boundary Content-Type: text/html; name="lunar urls.html" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline; filename="lunar urls.html" Subj: =09No Subject Date: =09Thursday, March 29, 2001 6:39:24 PM From: =09 Bookmarks for Kelly

Bookmarks for Kelly

The G= alaxy Page (U of AZ SEDS)
Jonathan's Space Home Page
Mark Wade 's Encyclopedia Astronautica
Mark Maimone's Home Page (text only)

Space Future web journal

Space Future Journal
Space Future=
Space Future - Li= nks to Other Sites
= Space Future - Topics
Space Future -=20= Artificial Gravity and the Architecture of Orbital Habitats
Space Future - Access to Space: SSX
Papers & Publications

SpaceViews: The Online= Publication of Space Exploration

SpaceViews: T= he Online Publication of Space Exploration

New Space journal

New Space Journal
Mi= nimum Cost Design
A Rocket A Day...

Livermore papers on sp= ace flight

Library Documents On-line Search Results

Space advocacy Groups

Space Access So= ciety
Space Tr= ansportation index
= British Interplanetary Society
National Space Society
The Mars Society= - The purpose of the Mars Society is to further the goal of the exploration= and settlement of the Red Planet.
The L5 Develo= pment Group, Inc.
Space Studies Institute=20= (SSI)
Space Studies Institute=20= (SSI)
Welcome to (First Millenial Foundation) InfoGuide
The First Millenn= ial Foundation
Northern Winds Mars=20= Page
The Mars Society= - The purpose of the Mars Society is to further the goal of the exploration= and settlement of the Red Planet.
Sta= rFire Space Society

Aerospace corporation site= s

ENERGIA LTD.
Scaled Composities
Welcome to Pra= tt & Whitney
Lockheed Martin Corpora= tion
Lockheed Martin Skunk Works
Northrop Grumman C= orporation
Computer Sciences Corporation Homepage
Lockheed/Martin home page
McDonnell Douglas Home
Rockwell home page
United Space Al= liance
The Boeing Home Page
Hughes Electronics Corporation
Whittaker Corporation Si= te Homepage

Truax Engineer= ing, Inc.

Space Future - Tech/design= concept articals

Sp= ace Future - What's New
Space Future - Space Vehicles
Space Vehicles - Vehicle Designs
Space Future - Access to Space: SSX
Space Future - A Single-Stage-to-= Orbit Thought Experiment
Space Future Journal - Classic Papers Prese= nted
Space Future - Getting to Low Earth Orbit
Space Future - The Future of Commercial Airli= nes
Space Future - RLV Design O= ptimization for Human Presence in Space
Space Future - Space Activit= ies, Space Tourism and Economic Growth
Space Future - General Public Space Tra= vel and Tourism
Space Future - General Public=20= Space Travel and Tourism Volume 2 - Workshop Proceedings

Discovery Online -- Space Entrepeneurs, Reusable Roc= kets
RLVCountdown +++!
NASA=20= Watch RLV list
Spa= ce Settlement
B= uilding Dreams From Moondust
T= he Space Settlement FAQ by Mike Combs

Space Commercialization Pr= ojects

Space Future - Economically Viable Publ= ic Space Travel
Commercial Space Transportation Study Web version top-level i= ndex

Space Dev - commercial= exploration

SpaceDev - Home=
SpaceDev, Inc.=20= is engaged in the commercial development of space.

Transp= ortation economic factors - of Earth, lunar and asteroidal materials
PERMANENT - Project= s to Employ Resources of the Moon and Asteroids Near Earth in the Near Term<= /A>

Asteroid Materials

World Sp= ace Conference 1992 neo fuels
World Sp= ace Conference 1992 neo fuels
NEEP 602 Lecture #16
SpaceViews Article: Astronomers Discover Fastest Spinning Asteroid Yet
As= teroids: astrogeologic theory, compositions, types and numbers
Asteroid Mining
S= pace Future - The Technical and Economic Feasibility of Mining the Near-Eart= h Asteroids
Space Future - Mining Economics and Risk Control in the Developme= nt of Near-Earth-Asteroid Resources

permanent.com Book on sp= ace mining

H= TML PERMANENT: Asteroids for Space Development, Commercialization and Coloni= zation
Transportation economic factors
Asteroids Near Earth : Retrieval for Materials Utilization
Asteroids: astrogeologic theory, compositions, types and numbers
Mining and processing an asteroid

Space Tourism Projects=

Space Future - Spa= ce Tourism and its Effects on Space Commercialization
Space Future - The Space Tourism Industr= y in 2030
Space Future - Feasi= bility of Space Tourism "Cost Study for Space Tour"
Space Future - Space Tourism i= n Japan - the Growing Consensus
Space Future - Collaboration with Aviation - The Key to Commercialisation=20= of Space Activities
Space Future - General Public Spa= ce Travel and Tourism
Space Future - General Pub= lic Space Travel and Tourism Volume 2 - Workshop Proceedings
Richard Branson is considering
Practical=20= Tourism in Space
Space Tourism - How Soon Will it
Discovery Online -- Space Entrepeneurs, Space To= urist
Your Spaceflight Manual: How you could be
Space Future -=20= Artificial Gravity and the Architecture of Orbital Habitats
Rocket rides for Space Tourism & Civilian Astronauts Corps
MSN= BC - Turning space into a tourist getaway
Spacetopia Ja= panis space tourist company
THE SUNDAY TIMES: NEWS Hilton pla= ns hotel on moon - with a beach

HobbySpace - Space Tourism

PERMANENT: As= teroids for Space Development, Commercialization and Colonization
List Of The Potentially Hazardous Asteroids
S= pace Colony - Geometries
Space Future - Artifici= al Gravity and the Architecture of Orbital Habitats
Lunar= Bases, Colonies, the Industrialization of Space and the Colonization of the= Solar System

International= Lunar Exploration Working Group
Lunar Underground Web Ring
LunarBase

What Goes Up | Living and Working in Space: A History of Skylab | NA= SA SP-4208

--part1_3b.12851d3e.27f551c3_boundary-- From VM Fri Mar 30 10:08:42 2001 X-VM-v5-Data: ([nil nil nil nil nil nil nil nil nil] ["560" "Wednesday" "28" "March" "2001" "11:04:14" "-0700" "Ben Franchuk" "bfranchuk@jetnet.ab.ca" nil "14" "Re: starship-design: Cryogenic Suspension" "^From:" nil nil "3" nil nil nil nil nil] nil) Content-Length: 560 Return-Path: Received: (from majordom@localhost) by darkwing.uoregon.edu (8.10.1/8.10.1) id f2U3u5t22779 for starship-design-outgoing; Thu, 29 Mar 2001 19:56:05 -0800 (PST) Received: from main.jetnet.ab.ca (root@jetnet.ab.ca [207.153.11.66]) by darkwing.uoregon.edu (8.10.1/8.10.1) with ESMTP id f2U3u3o22759 for ; Thu, 29 Mar 2001 19:56:04 -0800 (PST) Received: from jetnet.ab.ca (dialin53.jetnet.ab.ca [207.153.6.53]) by main.jetnet.ab.ca (8.9.1/8.9.1) with ESMTP id UAA26124 for ; Thu, 29 Mar 2001 20:55:58 -0700 (MST) Message-ID: <3AC2279E.F6187E56@jetnet.ab.ca> X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.2.18 i586) X-Accept-Language: en MIME-Version: 1.0 References: <36.13b4c83c.27f551bb@aol.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk Reply-To: Ben Franchuk From: Ben Franchuk Sender: owner-starship-design@lists.uoregon.edu CC: starship-design@lists.uoregon.edu Subject: Re: starship-design: Cryogenic Suspension Date: Wed, 28 Mar 2001 11:04:14 -0700 KellySt@aol.com wrote: > > I don't know of anything online. I saw it on tv. I know they were doing it > on organs, but I'm not sure if they tried lab animals. > > Kelly Sure what happens after 50 light years of travel and when you recover from the deep freeze the computer put you back with the WRONG body parts? HAL 9009 -- sorry dave but that SEX change was for your own good. -- -- "We do not inherit our time on this planet from our parents... We borrow it from our children." "Luna family of Octal Computers" http://www.jetnet.ab.ca/users/bfranchuk