Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V10_3/V10_326.TXT

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Subject: SPACE Digest V10 #326

SPACE Digest                                     Volume 10 : Issue 326

Today's Topics:
   Explanation: Foreign nationals applying to NASA summer positions
              Multiple responses
               Re: Mars Mission Agenda
                   Motives
----------------------------------------------------------------------

Date: 8 Dec 89 19:29:21 GMT
From: [e-mail]  (Eugene Miya)
Subject: Explanation: Foreign nationals applying to NASA summer positions

I have gotten a good deal of mail from foreign national students seeking
summer positions with NASA.  Permit me to explain an elaborate.

The National Aeronautics and Space Administration (NASA) is an
Agency of the United States Government Executive Branch.  As such
its employees are civil servants.  It is empowered to only hire
US Citizens, and in fact there are citizenship requires placed
on Naturalized Citizens (some number of years).  A few positions
also requires security clearance, not so for summer jobs (or
temporary work).

The situation with NASA summer employment is done on a Center by Center
basis on a year to year basis.
Some Centers hire people like the Forest Service hires seasonal rangers
and make them civil servants.  Some Centers in the past (Marshall Space
Flight Center) have had no summer programs (might be different this year).

As an example Ames Research Center uses nearby San Jose State University
as a summer contractor.  THEY can and do hire foreign nationals for
some summer positions to find the best qualified.  YOU MUST CONTACT
EACH CENTER AS THESE POLICIES CHANGE.  The only distinction is
the Jet Propulsion Laboratory where every one there is a contractor
[employees of the California Institute of Technology, a private contractor
not affiliated with the State of California].  Contact them separately.
They can take some foreign nationals.

Lastly, there are other contractors to the Government.  You must contact
these companies separately, they are the usual companies: Lockheed,
Rockwell, Computer Sciences Corporation (who does take high school
students).  You can contact the Centers for a list of these companies.
Their requirements might be more or less strict than the Governments, you
must contact to find out.

Another gross generalization from

--eugene miya, NASA Ames Research Center, [e-mail]
  resident cynic at the Rock of Ages Home for Retired Hackers:
  "You trust the `reply' command with all those different mailers out there?"
  "If my mail does not reach you, please accept my apology."
  {ncar,decwrl,hplabs,uunet}!ames!eugene
          Support the Free Software Foundation (FSF)

------------------------------

Date: 8 Dec 89 16:00:36 GMT
From: pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!wuarchive!kuhub.cc.ukans.edu![e-mail]
Subject: Multiple responses


(This article combines several responses in one message, both to cut down on
bandwidth and get around a problem I've been having with posting replies)

Jim Bowery writes:

>Henry Spencer writes:
>>In article <[e-mail]> [e-mail] (Jim
Bowery
>>) writes:
>>>>>... If you want to develop a propulsion system you do propulsion R&D.
>>>>Except that if you don't have a specific mission to use that R&D on, the
>>>>funds for it tend to get cut off.
>>>
>>>Uh.... Henry...  if you don't have a use for the propulsion R&D other than
>>>the mission it is supposed to "spin off" from...  where is it supposed to
>>>"spin off" to?
>>
>>The missions that can be flown *once the propulsion system is known to be
>>available*.

>Of course, this ignores alternative uses for that money -- for example,
>flying the hundreds of vital missions that can use existing space
>transportation systems which could come down in cost by a factor of 10
>with some reasonable economies of scale.  That way, the

Please, Jim. If the Wright brothers had your attitude, we'd probably still
be stuck on the ground instead of flying. With almost every new transport-
ation system I know of, there were alternative transports that could do
the job for less money, AT THAT TIME. Look at the car vs. the horse and
buggy, jet aircraft vs. propellor-driven, etc.

In addition, applications for new technology are rarely apparant when the
technology is being planned. Hypothetical conversation with an advocate
of jet airliners:

     "Well, what can it do that prop planes can't?"
     "Let's see... it can go farther and faster than prop planes."
     "What good will that do? The only ones who travel by plane are rich
      people who don't care..."

Would those people have imagined next-day air delivery, cheap, convenient
business travel, or any of the other benefits of air travel?  I doubt it.
It's just another variant of the "pure research" question, that is, "Why
should we (as a country) fund pure research if we don't know that anything
pratical will come from it?" My answer to your point is the same as my
answer to that question:  You CAN'T forsee what will come from new tech,
because it makes things possible that people couldn't imagine before.

                      *            *            *

On the whole question of underwater vs. space colonization:

You're comparing apples with oranges here. The two are similar because
both are hostile environments where man will need special habitats and
lots of protection to survive. But the resemblence ends there.

Undersea colonies have the benefit of readily available water and food.
It shouldn't be that hard to distill sea water to get drinkable water,
and food in one form or another is right outside the door (though I
imagine people would get tired of fish and kelp eventually). The sea
life would provide exploitable biological resources (as I remember,
you can get iodine from kelp, and I imagine other useful biochemicals
would be available there as well).

The problems of undersea colonies are pressure, temperature, sea life,
and power. Unavoidably high pressure causes great risk of the bends if
residents rise too close to the surface too quickly. The helium/oxygen
mixture used by Cousteau in Conshelf III for high-pressure living made
the habitants very difficult to understand. Water is a good thermal
conductor, requiring a lot of thermal protection (again, see Cousteau's
articles on Conshelf III). Power would be difficult to generate; you
can't practically burn fuels, and solar power isn't available. Cousteau
had to send power down through a cable to Conshelf III, a cable often
threatened by the weather (hence his remark that someone else quoted,
about surface support being more vulnerable than the undersea habitat).
Sea life can be hostile as well as beneficial; Conshelf II had serious
problems with some kind of stinging, biting undersea pest, if my
memory serves me.

Space colonies have cheap, virtually unlimited solar energy available
(though it has to be harnassed). Vacuum, and microgravity (if on a non-
planetary habitat) are useful manufacturing tools, and minerals would
probably be more available in space than undersea (undersea mining
seems quite difficult, as any digging would stir up sediment and make
it hard to see). There is no real concern with space pollution, though
there is a significant concern with ocean pollution. Vacuum is a good
insulator, and there are no external forces (such as sea currents) to
worry about structurally (except for meteorites, and they aren't a
big problem statistically, as I remember). The environment is more
stable.

On the other hand, space colonies have to be self-sustaining ecologies,
requiring much more work to maintain. Water and food are not nearly so
convenient as in undersea colonies. The threat of blowout and break-
down in environmental machinery is always possible, and the easy escape
that undersea residents would have (rising to the surface, possibly in
pressurized capsules to avoid the bends) is not there.

I could go on, but the point is fairly clear. Undersea habitiation and
space habitation are two very different questions, each with their own
strengths and weaknesses, and should be judged each on its own merits.
I think undersea colonies will aim at biological work and resources,
while space colonies will concentrate on industry and manufacturing.
But they are independent questions, and should be treated seperately,
not substituted one for the other as some have been trying to do.

                      *            *            *

Finally, here's one reader's response to my question on artificial
intelligence and space probes:

***  Message starts

Date: Thu, 7 Dec 89 12:19 EST
From: [e-mail]
Subject: AI for Unmanned probes?
To: [e-mail]

Feel free to post these comments if you wish.  Just don't expect me
to defend them...

(1) I am doing a thesis on planning, which is somewhat relevant to this
question.  I don't know anything about vision or robotics.

(2) Vision and visual interpretation are probably the most difficult
problems with using AI for probes.  Once you have an accurate
map of the area I think you can figure out where to go.  Current
systems have problems because visual features are mis interpreted.
For example, a tree trunk may look like a long black strip, i.e.
a road. Deciding where to drive based upon this interpretation is
certainly problematic.  (Wear your seat belts!)

(3) Nevertheless I think that autonomous probes are possible
given a reasonable level of support.  (Hint: The hubble space telescope
cost over a billion dollars as I recall.  Large funding levels *are*
possible.)  The basic reason for my optimism is twofold.  First, many
of the "failures" of AI are due to overambitious goals.  A research
project may attempt to build a system that is 100% autonomous, and
uses only visal information.  In other words, trying to build an
artificial human.  These kinds of constraints provide shape to a
research project, but are irrelavant to an engineering project.
The second related point is that people seem to have unreasonable
expectations and goals for an autonomous probe.

Start with the basic problem.  When mars is on the other side of the
sun from earth, it is about 15 light minutes away.  Hence two way
communication requires over 30 minutes, when it is possible at all.
Hence remote operation would be exceedingly slow, and it would have
to stop entirely during solar flares and eclipses.  The solution is
to make the probe respond to very high level commands at infrequent
intervals.  I.e. go five miles west and take a sample.  Or "Go 50
miles west taking a sample every 5 miles".  This  might take over a
day to complete, assuming the probe moves 5 miles an hour and spends
half of its time just sitting and trying to figure
out where it is safe to move.

Since this is engineering, not science, it is reasonable to give the probe
some ways to cheat.  For example laser or radar range finders and all
around 5 MPH bumpers.  Finally the probe should be designed to recognise
truly difficult situations and just wait for guidance from earth.

Such a probe should be able to function autonomously *for long periods*
with a high degreee of safety.   I think it could be built, and would
provide a very efficient way to explore another planet.

Chris Eliot
Umass/Amherst

*** Message ends

Travis Butler
University of Kansas, Lawrence

------------------------------

Date: 6 Dec 89 23:17:15 GMT
From: cs.utexas.edu!samsung!shadooby!sharkey!cfctech!teemc!mibte!gamma!towernet!pyuxp!pyuxe!nvuxr![e-mail]  (David Lewis)
Subject: Re: Mars Mission Agenda

In article <[e-mail]>, [e-mail] (Eric C. Garrison) writes:
>All this talk about which is better, manned or unmanned, is getting worn.
>Let's try a new game
> ...
> The object is to design a Mars landing/sample return mission, with minimum
> cost
> and maximum results.  There is a soft limit on the Budget at $200 billion,
> and a hard limit at $400 billion.

Define results.

(Seriously.  "Results" could, to an aerospace firm, mean "getting a
piece of that $200B."  Sounds like pretty awesome results to me.  You
want geological (marsological?) data?  Weather data?  Information on how
humans survive in the Martian environment?  It's not a trivial question.)

--
David G Lewis                    ...!bellcore!nvuxr!deej
    (@ Bellcore Navesink Research & Engineering Center)
            "If this is paradise, I wish I had a lawnmower."

------------------------------

Date: 8 Dec 89 02:50:18 GMT
From: ibmpa![e-mail]  (Nick Szabo)
Subject: Motives

In article <[e-mail]> [e-mail] (Peter Scott) writes:
>groucho![e-mail]  (Steve Emmerson) writes:
>
>>Our exploration of space is currently being funded, almost exclusively,
>>by the national government at the taxpayers expense.  In my opinion, it
>>doesn't appear to have a clear profit motive (except for the aerospace
>>industries ;-) and seems to have a rather weak scientific motive as
>>well.
>
>Why should it have a profit motive?  Granted this governs most of our
>activities, but might there not be a little more to human nature than the
>desire to turn a buck? Not a lot of profit motive in climbing Everest
>(I doubt they did it for the TV rights), but it happened anyway.

There are _many_ motivations, thus the need for the "profit motive."

Climbing Everest (the first time) cost less than $1 million.  Unmanned space
operations tend to be counted in the hundreds of millions, and manned
operations in the tens of billions (talk of spending $400 billion to go to
Mars is economic fantasy).  Such large sums of money are spent only by (a)
corporations that expect large returns on a traditional safe investment, or
_very_ large returns on a somewhat risky one, and (b) large governments on
traditional items (social programs, defense, science, infrastructure, and
occasionally national prestige.  The U.S. national prestige problem at the
moment involves Mitsubishi and Matsushita, not missiles).

Projects in the $1 million range can be funded by small groups of people
that share an interest (mountain climbing, saving the whales, launching
an AMSAT, etc.) that may have nothing to do with profits.  But there are
_many_ different motivations.  Larger sums of money require groups of
people too large to share a motivation to pay for any one project.  The only
way to get large groups of people to pay up is (a) return the money invested,
plus interest or profit, or  (b) force (taxation).

For any multi-billion dollar fund-raising, one or more of the following
must occur:

a) millions of people (or a lesser number of rich people) must share a
common interest in the project, strongly enough to donate billions of
dollars (this has never happened in world history).

b) a large government, or several governments working in concert, must
give it a priority higher than social spending, defense, tax cuts, etc.
which it might otherwise pursue.

c) it must return a profit, with no more risk than, say, the Alaska
pipeline project (which delivered a product with a proven large
market).

Currently (b) is the primary operator.  The original motivation of
national prestige from the 60's missile race has mostly faded into
transitory contractor lobbying by defense firms with excess capacity
and workforce.  Most of the high-price workers have already retrained
themselves and gone into different industries.  What is left produces
the Incredibly Shrinking Space Station.

So is this bad news for space fans?  Not if we can change our point
of view, and learn to live in the 1990's instead of the 1960's.  The
days of ten-billion dollar space projects are over.  The most productive
economy on our planet, Japan, engages in no such projects, and has no
intention to start. "Freedom", in a less productive capitalist economy, and
Mir, in a crumbling socialist empire, are the last gasp of socialist
gigaprojects.

If we can change our mindsets, these trends are very good indeed.  The
biggest space project of all, Apollo, had no intention of establishing
either industry or settlements in space.  Nor was it motivated by science.
Not surprisingly, Apollo ended up contributing little to either industry
or science, and produced no space settlements.  Future space projects
will be motivated directly by industry and science (and eventually, when the
infrastructure is ripe, space settlements).  They will do their job with
orders of magnitude more efficiency.  They will be small, risky, and diverse.
They can fail, and the failures will help us learn, instead of breaking the
bank.  Old, conservative methods--chemical rockets, large engineering
teams, and piles of paperwork--will be replaced by new and riskier forms
of organization and technology.  Workers, companies, and governments that
can't adapt will be left behind.  Technology will intertwine.  A company
producing artificial organs will decide to dabble in space, and blow away
traditional satellite makers.  A gold-mining company and a small-satellite
maker will join forces to survey and mine an asteroid, leaving Lockheed out
in the cold.  Drugs will be made in space, then a cheaper technique will be
found to make them on Earth.  (oops, that one's already happened :-)  And
vice versa.  Freedom and Mir will be sold for scrap.  The 60's will look
like the Mesozoic.  It's a jungle out there, and dinosaurs need not apply!

"If you want oil, drill lots of wells."
        J. Paul Getty

********* These are my opinions, not necessarily Big Blue's ***********
--
--------------------------------------------
Nick Szabo
[e-mail]
uunet!ibmsupt!szabonj

------------------------------

End of SPACE Digest V10 #326
*******************