[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Argosy Mission Overhaul

At 4:45 PM 3/9/96, Brian Mansur wrote:
> ----------
>From: L. Parker
>To: Brian Mansur
>Subject: Re: Argosy Mission Overhaul
>Date: Friday, March 08, 1996 11:30PM
>>From Brian,
>>Well, it sounds like a good idea to me, except I think I would reduce the
>>size of these ships to around 50 to 100 tons max and send more than one to
>>each destination, at least six.
>>I'm not much of a gambler, can you tell?
>>Using a combination of solar sails and lasers and RAIR we can get such a
>>ship up to around 0.4c fairly easily. Deceleration would have to be a
>>combination of drag screen and RAIR as well.
>Yesterday, AFTER I sent the mission overhaul letter, I went to the mall and
>found a book called _The Physics of Immortality_.  It described Neumman
>probes (I think I spelled that right) that were launched to the nearer stars
>(including TC!).  These probes explored the system, replicated themselves,
>and launched to other stars.  It was a slow process of exploring the galaxy,
>but is worked simply because it assumed complete robotic automation that
>almost never failed.
>In theory we can and will develop such robots but that could be centuries
>into the future.  Assuming that lightsails are the fasted and safest forms
>of propulsion when and if the automation advances occur, humanity will
>expand by first sending his robots to the stars.  They will set up power
>arrays, laser cannons to decelerate incoming colonists, and some
>neighborhoods for those colonists to start new lives in.  They might also
>just terraform a few planets and moons while they are at it.

In that case the mission would be redundant, since their would be no
furtherreason to explore.

>Something that I have noticed about every design proposal on the board is
>that they almost all have to have high degrees of robotic automation.  That
>or they need A LOT of man power that we probably won't be able to support
>for a simple exploration mission.  Its a real bumber but that seems to be
>the deal.
>Think about it.  The maser/laser driven sails need 1E18 (probably  1E20 to
>account for efficiency) to fly.  That means planet size power arrays if the
>source is solar.  The RAIRs need lots of fuel that has to be packaged and
>put into position by some kind of infrastructure.  That _just_ might be
>within the capabilities of human manpower.  Anti-matter energy has to be
>made from an equal (or greater depending on efficiency) amount of energy.
> That equates to huge power stations to do the matter/anti-matter
>conversion.  Simply launching rockets with fusion pellets as their fuel
>(like the Daedalus) may be doable for small loads but we would quickly run
>out of rare isotope  fusion fuel.  Unless, of course, A LOT more could be
>made by some trick of physics involving fusion techniques perhaps.  Of
>course, a rare isotope factory would most likely require a huge power array
>to run it.

Fission reactors can generate rare isotopes if standard issotopes are used
as shielding mass.  Unfortuntly, unless we use them to power this mess.
There wouldn't be enough demand to requre that much power.

>There does seem to be some hope for an easier future, powerwise.  If this
>cold fusion thing that Tim alerted us do is not a hoax or is less fantastic
>discovery than it sounds like, we could be going places we thought were
>going to be out of our reach for decades and centuries.
>There is hope.  Let's keep trying.



Kelly Starks                       Internet: kgstar@most.fw.hac.com
Sr. Systems Engineer
Magnavox Electronic Systems Company
(Magnavox URL: http://www.fw.hac.com/external.html)