[ExI] pentagon wants orbiting solar power stations

[Eugen Leitl]

On Tue, Oct 16, 2007 at 11:55:01AM -0700, Samantha Atkins wrote:

> What of the possibility of autonomous and tele-operated robotic mining  
> of near-earth asteroids and space manufacture of some of the larger  

Autonomous self-replication, in a small package is hard. Nobody knows exactly 
how to do it yet. Even teleoperation with enough relativistic lag (which

	http://www.molecularassembler.com/KSRM.htm

implies distance, and large delta v) is hard.

The closest nontrivial amount of extraterrestrial material with low
delta-v and negligible (2 s ping-pong) is lunar surface. Even so bootstrapping
a fabbing/launch bridghead on the Moon is nontrivial, and might require
much cheaper launches than today. A useful package of material to deorbit
would seem in some 10-100 kg, which implies of putting a mass of about a 
ton into LEO (transfer time about half a year). Possible alternative
launch methods are a gas gun, or a maglev/scramjet, or carrier/scramjet
(anything else?). A ton is a lot for these. 100 kg LEO is more realistic.
100 kg spun int 10 um material goes a long way.

> solar sat components?  If possible it would help avoid having to drag  
> so much out of the gravity well.   Not to mention that extraction of  
> bullion (!), metals and combustibles is space could generally greatly  

At current launch costs, material put to LEO could as well be solid gold.
On the other hand suitably sheathed material can be deorbited and aerobraked.
This might or might now work out for lunar materials. 

> enhance space opportunities.    I heard about such things ages ago but  

I don't see how suited or canned monkeys have much of a future in space.
The logistics is very much different for solid-state beings which travel 
to the resources and multiply there. This even applies to people, though
less so.

> haven't seen a lot since.

-- 
Eugen* Leitl <a href="http://leitl.org">leitl</a> http://leitl.org
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