Re: Re: Re: Re: Re: starship-design: Re: Perihelion Maneuver

[KellySt@aol.com]

In a message dated 11/29/97 5:54:21 AM, kuo@bit.csc.lsu.edu wrote:

>KellySt@aol.com wrote:
>>In a message dated 11/27/97 3:09:43 AM, kuo@bit.csc.lsu.edu wrote:
>
>>>That is a big deal!  Do you have any idea how to do VLBI with
>>>visible wavelengths?
>
>>>If so, there's a Nobel Prize waiting for you.
>
>>>We can do VLBI with microwave wavelengths because it's just barely
>>>possible to measure phase with them (and thus possible to receive
>>>multiple signals and constructively interfere them appropriately).
>
>>>We _can't_ do VLBI with infrared and shorter wavelengths.  It _might_
>>>be possible to do it in the future, but don't bank on it.
>
>>Actualy we do currently do VLBI with optical ground telescopes, and NASA is
>>tinkering with a project to scatter 1 meter drone scopes across an area of
>>hundreds of miles of lunar surface.
>
>We do LBI with optical ground telescopes.  So far as I know, VLBI is
>impossible with known technology.
>
>The V in VLBI stands for "Very".  What that means is that the elements
>are so far apart that they aren't rigidly locked wrt to each other
>within the tolerance of about 1/4 the working wavelength.
>
>The moon's surface provides a very stable nearly rigid "structure"
>to lock a bunch of elements wrt to each other, but this isn't necessary
>with VLBI.

A few sats parked on lunar soil is hardly a structure "rigidly locked to each
other
within the tolerance of about 1/4 the working wavelength."

Also we do synthetic appiture imaging over 100's of yards or even kilometers
of fighters and space craft.  So if you prefer we could consider that as an
example of VLBI using one insterment over a period of time.

>>>>>> Or funding sources that much more patent?  If it take a half
>>>>>>century to get results, a inteligent person will wait a couple
>>>>>>decades for faster cheaper systems.
>
>>>>>Not if those "faster cheaper" systems aren't going to be much faster or
>>>>>much cheaper.
>
>>>>When have we not developed much better systems after a few decades?
>
>>>For instance, automobiles.  Automotive technology has gotten a bit
>>>better, but a 1960's Cobra can race competetively with anything
>>>we can build today of similar weight/size.  A 1940's Volkswagon
>>>is still one of the most fuel efficient vehicles you can drive.
>
>>>Cars are a bit better, but not outrageously better, than several
>>>decades ago.
>
>>Cars speeds are governed by highway speed limits.
>
>Not on the racetrack.

Especial on race tracks.


>>Unrestricted the max speed
>>for a car a hundred years ago was tens of miles per hour, just recently
>>supersonics (700+) were runing.
>
>Not on the racetrack.

So?  .. actually it was on a race track.

>Admittedly there was a vast improvement in automotive technology
>between 100 and 50 years ago.  However, since then improvement
>has largely leveled off.

You really need to read more.  Auto tech has imptoved dramitically in
performance, effocency and cleanlyness.  Sports cars now produce more
horsepower with engines that were tiny by 1960's standards, while producing
about 1/40th the polution, and with better relyability then any car of the
60's.


>>Oh and gas milage and the rest for cars a decade or so old are fairly bad
by
>>current standards.  (Top fuel efficent cars from the dealership can get up
to
>>100 mpg, thou few are very drivable.)
>
>Anyone knows that car fuel efficiency depends upon the car's
>size/weight.  Comparing cars of equivalent size/weight, we haven't
>improved gas mileage much.

False again.


>Well, since you seem unconvinced by what I deemed a blatant example,
>I'll give another--small arms.  Today's military small arms don't
>significantly outperform those from 40 or 50 years ago except in
>improved reliability.


Theres no reason to since the military personel of today can't point
significantly more acurately then those of 40-50 years ago.  Top end
competitian and hunting guns are much more accurate (pistols that keep a
pattern within 3 inches at a could hundred yards are on the market) but
they'ld serve no military purpose.

This is geting tedious and way off topic.

Kelly