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Subject: SPACE Digest V10 #337

SPACE Digest                                     Volume 10 : Issue 337

Today's Topics:
         Re: manned v unmanned (exploration of Mars)
       Compton named Ames Research Center Director (Forwarded)
          Re: V10 No.327 and inflammatory ephithets
           Re: Multi-national (MANNED) Mars Mission
             precession obsession
           Payload Status for 12/11/89 (Forwarded)
----------------------------------------------------------------------

Date: 11 Dec 89 14:43:17 GMT
From: zaphod.mps.ohio-state.edu!samsung!munnari.oz.au!basser!cluster![e-mail]  (Raymond Lister)
Subject: Re: manned v unmanned (exploration of Mars)

Since the subject has come up, I thought I'd share a newpaper feature
article I wrote, but never sold ...

-----

SHOULD we, like the crew of the starship "Enterprise", boldly go where
no man has gone before? Or should we be content to send a robot?

Now, with the recent completion of Voyager II's survey of the outer
planets, and as NASA still struggles to launch its shuttle fleet and
recover from the the Challenger explosion, the question seems
particularly poignant.

But the argument is as old as spaceflight itself.  NASA has always been
split into supporters of manned and unmanned space exploration, but in
the early days of the fifties and sixties, the space Budget was large
enough to support both camps, so the rivalry was good natured.

The friction didn't cause heat until the progressively tighter Budgets
of the 1970s. In order to keep shuttle development going, NASA slashed
its unmanned program.  James Van Allen, the famous space scientist,
after whom the earth's radiation belts are named, called the cutbacks
"the slaughter of the innocent".  The launch earlier this year of the
Magellan probe to Venus was NASA's first unmanned interplanetary launch
since the Voyager probes twelve years ago.  The recent launch of the
Galileo probe to Jupiter was years behind the original schedule, due to
cut backs in its funding in order to maintain the shuttle program.  The
rivalry between the manned and unmanned sections of NASA is now far
from friendly.

NASA's unmanned camp have every reason to be angry with the manned
supporters, and to feel very pleased with the performance of Voyager
II, but their little champion has not demonstrated that manned space
exploration is an unnecessary extravagance.  Despite all the excitement
about Voyager's Neptune encounter, despite all the computer time
consumed in calculating its trajectory, despite all the person hours
that went into nursing the geriatric craft along, the fact remains that
the tasks Voyager performed are very simple. The scientific return is
so great only because Earth based telescopes tell us very little about
the outer planets, and no other probe has ever been to Neptune before.

Now that Voyager has completed the initial survey, future missions will
attempt the much more difficult act of rendezvous and and direct
physical contact with the outer planets and their moons.  Its a task
that will require great intelligence. The question is, should that
intelligence be natural or artificial?  Thus far, we have only achieved
contact with three heavenly bodies -- the moon, Venus, Mars -- and the
experience has highlighted the limitations of robots and the power of
the human mind.

The Apollo 11 lunar module's computer would have crashed the "Eagle" in
a field of boulders, had Armstrong not taken control and found a safe
landing site.  In contrast, even while Tranquillity Base was still
manned, the unmanned Russian probe Luna 15 crashed on the moon, in what
some believe was Russia's last desperate attempt to grab some moon
dust, and some glory, before the Americans.

Venus is perhaps the robot's only complete victory.  No amount of the
"Right Stuff" will protect an astronaut from an atmosphere around 100
times as dense as our own, and temperatures exceeding 400 degrees
Celsius.

July 20th is not just remembered (at least in American time zones) as
the day when the first men landed on the moon. On that day in 1976, the
robot probe Viking I landed on Mars, to search for life.
Unfortunately, Viking gave the worst possible answer, not that life was
absent,  but that it wasn't sure.  Two of the three life experiments
said "yes", and the other (ironically, the one given the best chance of
finding signs of life) said "no". Either there is life on Mars, or, as
Mr. Spock might have put it, "It's soil chemistry Jim, but not as we
know it".  Viking wasn't smart enough to decide either way.

Contact was lost with one of the two Viking landers when a technician
mistakenly transmitted a command to move the radio dish.  Viking
obliged, contact was lost, and the robot wasn't bright enough to
restablish contact.

Undaunted, NASA still plans to send a robot rover to Mars.  It takes a
radio signal several minutes to travel between Earth and Mars, so any
vehicle will have to be autonomous.  As anyone who has ever driven an
off road vehicle would testify, it will take a skilled driver to
negotiate the boulders and sand dunes of Mars.  The state of the art is
a robot called the Autonomous Land Vehicle, and it crawls around a set
of specially made concrete paths, attended by a gaggle of computer
scientists, at its home in Carnegie--Mellon University, Pittsburgh.
The ALV's can "see" through a video camera, and uses it to look for the
road.  Describing what a road looks like to a robot is only marginally
easier than describing it to a blind person.  The ALV has been
programmed to look for a bright region (the concrete) surrounded by a
darker region (the ground).  However, at any time, there are probably
several bright regions in the camera's field of view, such as the sky.
So, the ALV's attendants have programmed in a number of tricks, called
"heuristics" in the artificial intelligence business, for telling which
bright region is the road.  One of these tricks says that the the road
should have two near vertical straight sides, and narrow at the top of
the image (due to perspective).  This heuristic worked very well, until
one day when the multi--million dollar ALV mistook a tree for the road.
("Oh well!  Back to the drawing board.")

Fortunately, there are no trees on Mars.  Unfortunately, there are no
concrete paths.

Recently, I watched my nine month old godson explore his lounge room.
He spotted something interesting (try programming "interesting" into
your Macintosh!), safely negotiated his way through a maze of chair
legs, reached out, grasped the object, and ... put it in his mouth.  No
student of Artificial Intelligence can watch a baby, and not be
humbled.

The Mars rover is typical of the American taste for technological
overkill.  The Russians have a delightfully simple plan for their first
survey of the Martian surface, using a solar powered balloon.  During
the day, the balloon will heat up, expand, and float through the thin
orange--yellow Martian sky.  At night, it will cool and sink, lowering
its instrument package to the red Martian soil.

However, neither a rover nor a balloon will settle the old question "Is
there life on Mars?" We won't know for sure, at least in our lifetime,
unless people go there with a well equipped laboratory.  Only people
have the necessary flexibility and sophistication.  Those who think
otherwise watch too much science fiction.

The question of unmanned versus manned space travel is really a
question of short term versus long term goals.  Voyager II is one of
the great technical accomplishments of the 20th century, but when
compared with the 21st century potential of manned space flight -- the
search for life on Mars, for minerals among the asteroids -- the data
it returned resembles the work of an amateur photographer on vacation
("See! That's me. Next to Triton.").  Robots aren't very good at coping
with the unexpected, or as Neil Armstrong once said, in an
uncharacteristically poetic way, "man can be amused and amazed and a
robot can be neither".

"Star Trek" is immensely satisfying entertainment, not because of
Klingons and phasors, but because of its message about the power of the
human mind.  As we peer far into the future it is possible to imagine
computers capable of matching Mr Spock's Vulcan logic, but as is shown
in every episode of "Star Trek", logic has its limitations, and Captain
Kirk's human intuition will prove essential for exploring the final
frontier.

Raymond Lister
Basser Department of Computer Science
University of Sydney
NSW  2006
AUSTRALIA

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

Date: 11 Dec 89 20:21:13 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Compton named Ames Research Center Director (Forwarded)

[A bit of NASA news, even if it isn't quite space related. -PEY]

Mary Sandy
Headquarters, Washington, D.C.                  December 11, 1989

Del Harding
Ames Research Center, Mountain View, Calif.


RELEASE:  89-182

COMPTON NAMED AMES RESEARCH CENTER DIRECTOR

    NASA Administrator Richard H. Truly today named Dale L.
Compton as Director of the NASA Ames Research Center, Moffett
Field, Calif.  Compton's appointment becomes effective on
December 20, the 50th anniversary of the center's groundbreaking.

    Compton, who succeeds Dr. William F. Ballhaus, has been
Acting Director since Ballhaus' resignation on July 15.

    Compton previously served as Acting Director for the Center
from February 1988 to January 1989.  He served as Deputy Director
of Ames with line management responsibility for the center's
facilities, personnel and programs from 1985 to 1988 and from
January through July 15, 1989.

    As Director, Compton will be responsible for all research and
development programs and the overall management of the Ames
Research Center at Moffett Field and the Ames-Dryden Flight
Research Facility at Edwards Air Force Base, Calif.  Ames-Moffett
and Ames-Dryden, which have more than 5,000 employees, conduct
research and development programs in the fields of aeronautics,
life science, space science, space technology and flight
research.

    Compton's professional career has been spent with NASA Ames
where he served as a research scientist for 15 years and
published over 25 papers on aerodynamic and aerothermodynamic
subjects.  He also has served as Deputy Director, Astronautics;
Chief, Space Science Division; Manager, IRAS Telescope Project
office; and Director, Engineering and Computer Systems at the
Center.

    Compton was educated at Stanford University where he received
a B.S. degree in 1957, an M.S. in 1958 and a Ph.D. in
aeronautical engineering in 1969.  He was a Sloan Fellow at the
Massachusetts Institute of Technology from 1974 to 1975 and
attended the Harvard Advanced Management Program in 1986.  He has
received the NASA Outstanding Leadership Medal and is a Fellow of
the American Institute of Aeronautics and Astronautics.

    Compton and his wife, Marilyn, have two children.  They
reside in Cupertino, Calif.

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

Date: 11 Dec 89 23:58:32 GMT
From: thorin!cezanne![e-mail]  (Jonathan Leech)
Subject: Re: V10 No.327 and inflammatory ephithets

In article <[e-mail]> [e-mail] (Charles Balan) writes:
>In article <[e-mail]> [e-mail] ("Lee S. Ridgway") writes:
>>Not all of us "liberals" are not anti-space.
> ^^^                   ^^^ ^^^^
> Um, could someone from sci.lang please help me out here.  What exactly is
> being said?  All of us "l's" are anti-space?    No "l's" are anti-space?
> I'm completely befuddled.

    What's being said is that people who feel compelled to flame
signatures that may or may not represent the view of their poster,
shouldn't do it in this newsgroup.
    Followups redirected to alt.flame. Please.
--
    Jon Leech ([e-mail])    __@/
    ``There ain't hardly nothin' cuter nor a sleepin' baby tad
      lessen it's a pork chop'' - Churchy La Femme

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

Date: 11 Dec 89 19:38:23 GMT
From: mentor.cc.purdue.edu![e-mail]  (Floyd McWilliams)
Subject: Re: Multi-national (MANNED) Mars Mission

In article <[e-mail]> [e-mail] writes:
[Speaking of a World Space Agency:]

>  The World Space Agency formed to oversee a Mars mission would serve
>  as the foundation for a more agressive exploration/colonization
>  effort with ( hopefully ) more vision and commitment then any one
>  nation could possibly keep up by itself for long.

    The problem is that you're assuming two things:

    1.  A World Space Agency will have the same goals w.r.t. space
exploration that you do.

    2.  These goals are necessarily the best for all parties interested
in space.

    Establishing an pan-governmental agency receiving funds from many
wealthy nations would probably create a super-bureaucracy whose sloth,
narrow vision, and pettiness would far surpass anything ever exhibited
by NASA.  (Stick around sci.space and read what Spencer, Bowery, Neff,
Szabo, et al have to say about our space agency.  It's bad.)
    But even if this monolith does somehow retain a vision, and puts
together a (presumably enormous) plan to conquer space, who's to say that
plan will be correct?  Why put all the world's eggs in one basket?
Having space agencies and private corporations compete encourages
diversity and efficiency.
    Going even further, what does "correct" mean?  Will the Defense
Department have the same space transportation goals as a comsat company?
Why not let them both develop their programs in parallel, rather than
forcing them to compete for the nihil obstat of the WSA?

>  And foremost (IMHO) it  would serve to excite  (most)  of the worlds
>  people and bring a vision of a United ( Ok, Confederated) World reaching
>  out to the planets, then one day the stars, Closer.

    This is a nice, warm-fuzzy kind of attitude, but the more I
think about it the less I like it.  To say that a united and visible
space program will end war and injustice is to say, in effect, that
the criminals of this world -- whether holding positions of power, like
Comansceu, Amin, and Pinochet, or roaming on murderous rampages across
the countryside, like Ramirez and Bundy -- got that way because they
never had a chance to get their rocks off on reruns of "The Right Stuff."

--
"You can broadcast any opinion, but it has to be on the opinion hour.
 You cannot hide it in a song and say it is entertainment." -- Shlomo Kor,
Israel Broadcast Authority's deputy chairman.
Floyd McWilliams            mentor.cc.purdue.edu!acu

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

Date: Mon, 11 Dec 89 02:15 PST
From: Bill Gosper <[e-mail]>
Subject: precession obsession
To: "[e-mail]"@ELEPHANT-BUTTE.SCRC.Symbolics.COM
Cc: [e-mail]

(Why is it you can never find an orbital mechanic on weekends?)

Can one fudge both the 559 mile altitude and the inclination of
COBE's orbit so as to preserve the sun-synchronous precession?
If the orbit were extremal in either altitude or inclination,
would there be two altitude vs inclination curves along
which to back away?  More likely, the orbit is extremal in
inclination to the ecliptic.

Just as a sphere has the g field of a point, can you reduce an
oblate spheroid to a disk?  A hoop?  The one through the foci?
If not in general, for one altitude?

Can someone give data points on the radius vs inclination curve
for 1 deg/day ("earth synchronous") solar "polar" orbits?  Was
such an orbit intended for the solar polar probe?

"Three days on the net can save an afternoon in the library."

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

Date: 11 Dec 89 23:02:00 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Payload Status for 12/11/89 (Forwarded)

Daily Status/KSC Payload Management and Operations 12-11-89


- STS-31R HST (at VPF) -

HST power on testing was completed on Saturday.  No more testing
is planned until after December.  There is the removal of a SIC
and DH planned for today to gain access to a CU/SDF (electronic
box) which has suspect, bad electronics, and solder joints.

- STS-32R SYNCOM (at Pad A) -

SYNCOM battery charging was performed yesterday and will continue
after orbiter hyper load.

- STS-35 ASTRO-1/BBXRT (at O&C) -

Completed the Spacelab experiment train interface test over the
weekend and picked up with the mission sequence test.  Mission
sequence testing picked up again this morning.

- STS-40 SLS-1 (at O&C) -

Rack structural mods worked several racks over the weekend.  Plan
to have eddy current checks and rack rotations performed today.

- STS-42 IML (at O&C) -

Light weight handling frame mods are three quarters percent
complete.  Rack bumper removal was worked on the weekend.

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

End of SPACE Digest V10 #337
*******************