From: roberts@cmr.ncsl.nist.gov (John Roberts)
Subject: Re: Lunar "colony" reality check, part 2
X-Added: Forwarded by Space Digest
Organization: National Institute of Standards and Technology formerly National Bureau of Standards
Original-Sender: isu@VACATION.VENARI.CS.CMU.EDU
Distribution: sci
Date: Wed, 18 Nov 1992 04:32:34 GMT


-From: szabo@techbook.com (Nick Szabo)
-Subject: Lunar "colony" reality check, part 2
-Date: 15 Nov 92 11:48:05 GMT

-* Just as with Shuttle, astronauts will not be able to fix most 
-  broken equipment.  Most disabling breaks, no matter to how 
-  small a part, will require an entire replacement unit to be 
-  shipped from earth.  Since the astronaut's very lives will 
-  depend on recycling equipment, large numbers of spares will 
-  have to be shipped on the first trip.

A valid concern, and one I have posted before. What can be done to help
alleviate the problem? Breaking designs up into smaller modules, and having
as many identical modules as possible might help. Using initially identical
but reconfigurable modules could also be useful. (Earthbound example: I just
finished a circuit design in which a high percentage of the logic is in
identical reprogrammable logic devices, each one programmed differently.
By keeping a relatively small number of spares on hand, I could replace
any of these devices that might fail. If for some reason I had no spares 
and really needed to use the circuit, I could cannibalize a component from
a less-critical area, and use it to replace a failed device in a more-critical
area.)

As I posted long ago, I suspect a first mission would be likely to choose to
start with a minimal set of spares, and hope to later build up a stock by
periodic resupply. (Or they might send supplies ahead of them, by unmanned
vehicle.)

-* Redesigning equipment for 1/6 g will cost _more_ than
-  redesigning it for 0 g, because the latter has been
-  done for a much wider array of equipment on satellites
-  & stations.

With so many Earth-based processes relying greatly on gravity, can you be
sure that low gravity will be worse than none at all? Experience with
chemical processes in microgravity is very limited - not counting rocket
engines (which I don't think of as a *process* anyway), I can't think of any
non-classified work except film development, and that was done using gels.
(Obviously, there are ongoing Shuttle experiments on processes that
*require* microgravity.)

Are you thinking in terms of large rotating structures in space to provide
gravity? That approach can introduce its own problems.

-* Unlike the intrepid Biosphereans, lunar astronauts will
-  not be able to cheat and come back to civilization to
-  find good medical care.  In a lunabago will be found
-  little more than a part-time doctor and a first-aid kit.

That's also a concern for SSF. Would a crew return to Earth two months
early to reattach a severed fingertip?

Some of the Shuttle experiments have involved equipment and techniques
that would be useful for medical treatment in orbit - they could
certainly make sure at least one SSF astronaut is a physician, and
perhaps surgery would not be out of the question.

On her first flight (the Spacelab mission), Dr. Tammy Jernigan showed that
if the Shuttle pilot is strapped down onto the experimental restraint table
for sick crewmen, he can safely be whacked over the head and/or tickled
with an artificial arm without fear of immediate retribution - thus proving
that the restraints are effective. (On the recent STS-52 mission, however,
she was unfortunately dragged off by a 'space alien' during the Halloween
celebrations - showing that these things balance out in the long run.)

-* Submarines get to surface every month or more, and can come back to 
-  port for food & sex.  Nobody has a "submarine colony", even though
-  it would be far less expensive and more functional than a lunar 
-  "colony".

I know one person who actually served on a nuclear attack sub. Judging from
his (unclassified) account, I don't think they surfaced for months at a
time. 

-* If scientific knowledge is an "economic resource", then what
-  happened to NASA's planetary science budget?  Why can't they
-  even find money for a lunar polar orbiter, which costs many
-  orders of magnitude less than even a minimal lunar base?   
-  Why not let scientists decide where to spend the science budget? 
-  (Hint: lunar base isn't even _on_ their long list of priorities).

Some might argue that the overwhelming interest of scientists is to
publish as many papers as possible (to the extent that many journals
actually charge the authors to publish their papers), and that for a
given amount of money, you can get a lot more speculative papers on
fuzzy blobs seen from Earth. I think that would be too harsh an accusation -
I'm sure there are many dedicated scientists who are mainly interested
in scientific truth. But I'm not convinced that the scientists should be
given the sole voice in deciding what should be funded. None of the scientists
I know get to spend on whatever they want without approval from Administration.

-* Microgravity manufacturing, large platforms and other space
-  industries could export $10's of billions per year to earth
-  by using a large supply of cheap volatiles and high-grade metal 
-  regolith, available in abundance from planetesimals but absent 
-  on the moon.  With low thrust in microgravity, the power needed 
-  to move this material to earth orbit is orders of magnitude less 
-  than needed to get useless lunar material out of the moon's gravity 
-  well. 

-Our obsession with the Death Valley in front of us continues
-to blind our eyes to the fertile valleys beyond, and the space
-colonization movement remains mired in failure.

"And your friends on the forest moon will not survive." :-)

Well, one improvement anyway - nobody's going to be able to dispute
the *numbers* in your post. :-)  :-)

John Roberts
roberts@cmr.ncsl.nist.gov

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