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

In a message dated 11/27/97 3:09:43 AM, kuo@bit.csc.lsu.edu wrote:

>KellySt@aol.com wrote:
>>>>But Telescopes can get results quicker and certainly can get as good a
>>>>optical resolution from here.
>>>Actually not.  Remember that resolution is proportional to the distance
>>>from the observed object.  A Voyager-like probe could fly by an
>>>atmosphere-less planet a kilometer from its surface.  That gives it
>>>at least a 4x10^13 advantage in resolution compared to a Solar System
>>>telescope.  Assuming the Voyager-like probe had a camera with a 1cm
>>>lens, the Solar System telescope would need to be at _least_
>>>4,000,000,000 kilometers in diameter to equal it.
>>I.E. about 10 light secounds.  Lunar orbit is 3 light secounds, earth orbit
>>is about 960 light secounds.  So a 10 light secound array isn't that big of
>>deal.  Certainly far cheaper and quicker then launching a interstellar
>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.

To my knowledge no one was expecting a Nobel.


>>>> 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.  Unrestricted the max speed
for a car a hundred years ago was tens of miles per hour, just recently
supersonics (700+) were runing.  Aircraft have gone from walking speed to
well over mach 6 (5000+), rouckets of course go far faster.

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.)