Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_3/V16NO314.TXT

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Date: Mon, 15 Mar 93 05:08:44
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #314
To: Space Digest Readers
Precedence: bulk


Space Digest                Mon, 15 Mar 93       Volume 16 : Issue 314

Today's Topics:
                   aA scite for orbital elements?
       Auto-cancel would be legit with a distribution (2 msgs)
                                Blimps
                           Building WF/PC-2
                 cancel wars accountability (2 msgs)
                       Charon: Planet or moon?
                        Huygens will float....
                          Planet X (2 msgs)
                          Retraining at NASA
                       Russians ICBMs -> SLVs
    Sisters of Mars Observer (was Re: Refueling in orbit) (2 msgs)
                       Tech-Life in the Galaxy
                       The courage of anonymity
               Venus and Mars, was Re: TIME HAS INERTIA

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

Date: 13 Mar 93 15:53:39 PST
From: [e-mail]
Subject: aA scite for orbital elements?
Newsgroups: sci.space,sci.astro

        Can anyone here suggest a site that would be interested in
maintaining an ftp-able archive of artificial satellite orbital
elements? The amateur community has accumulated probably a few tens of
megabytes of elements over the past several years, mostly through the
heroic efforts of a few individuals. The elements are currently
maintained on PCs and workstations where they are not particularly
accessible and are subject to local disasters.

       More recently, the NASA RAID BBS makes it practical for a
single user to update elements for all objects in the NORAD catalog on
about a twenty day cycle. Major objects (payloads and boosters) can be
updated on a cycle of five to ten days.  When supplemented with
amateur-derived elements for LEO satellites not officially listed,
these data should give a pretty complete picture of the larger
orbiting objects out to GEO. Estimated data volume is  < 150 kB
(ZIPed) per week. Unfortunately, the RAID board maintains only the
last five element sets for each object, hence the present query.

      The utility of such an archive is TBD, but geopotential studies,
debris modeling, upper atmosphere research, scheduling astronomical
photography, mission planning and analysis, and amateur/educational
satellite observing come to mind.

      Please mail me if you have a candidate site.

Disclaimer: The content of this message is my responsibility, not
            SAIC's.

,-------------------------------------------------------------------------,
|  Allen Thomson               |                                          |
|  SAIC, Inc.                  |      Tishe yedesh', dal'she budesh'.     |
|  McLean, VA, USA             |                                          |
|  [e-mail]     |                                          |
'-------------------------------------------------------------------------'

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

Date: Sun, 14 Mar 1993 21:13:25 GMT
From: Brad Templeton <[e-mail]>
Subject: Auto-cancel would be legit with a distribution
Newsgroups: news.admin.policy,news.admin,comp.org.eff.talk,sci.space,alt.privacy

One comment I will add.  The use of the auto canceller would be legit
if every article posted included a line like:

Distribution: autocancel-anon

People could then be welcome to join that distribution and get a feed
of it.

Of course, due to the design error in C news, this distribution would
leak and the cancel messages would still make it out to much of the
net.

But that's not a bad thing, because it would get people off their
duffs and have them fix their sys lines to remove "all" from distribution
lists.

(Actually, people would probably just keep all,!autocancel-anon, which
would not solve the problem.  I think for proper vigilante action to fix
the "all" problem one should write a flooder that just keeps posting
random text to random newsgroups with *random* distributions, random
distribution meaning "oidnmzce" and other meaningless strings of random
letters.)

This would force people not to say "all" in distribution lines fast.
--
Brad Templeton, ClariNet Communications Corp. -- Sunnyvale, CA 408/296-0366

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

Date: 15 Mar 1993 00:35:30 GMT
From: Steve Pope <[e-mail]>
Subject: Auto-cancel would be legit with a distribution
Newsgroups: news.admin.policy,news.admin,comp.org.eff.talk,sci.space,alt.privacy

[e-mail] (Brad Templeton) writes:

> One comment I will add.  The use of the auto canceller would be legit
> if every article posted included a line like:
>
> Distribution: autocancel-anon
>
> People could then be welcome to join that distribution and get a feed
> of it.

I disagree that this is "legit".  By arbitrarily deleting one
category of user from each usenet thread, you end up with
a "punctured" discussion in which different people have
read different subsets of the thread, and are trying
to carry on a coherent discussion despite this.

Sort of a step 10 years backwards in usenet functionality.

Further, there is the problem of determining fairly what is an
"anon" posting.  Anything from penet?  What about pseudonymous
users from access services, or bogus accounts at .edu
or .com sites?  Recall that the only reason people have
to post through penet is they don't have the $20 or
so per month it takes to buy a pseudonymous account.

It would seem that an "autocancel-anon" scheme is biased
against those with limited financial resources.

Steve

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

Date: Fri, 12 Mar 1993 09:45:00
From: Ron Lee <[e-mail]>
Subject: Blimps
Newsgroups: sci.space

This subject is one I would like some info on if possible..

What sort of lifting capacity is possible with a blimp (say the size of the
 Goodyear blimp)?

How long can they go without a lifting gas top-up?

What gases are used these days?

Hope you can enlighten me

regards
Ron

 * Origin: N A R N I A .. Proudly Australian.. Bittern Victoria (3:635/578)

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

Date: 15 Mar 1993 00:03:26 GMT
From: Francis Vaughan <[e-mail]>
Subject: Building WF/PC-2
Newsgroups: sci.space,sci.astro

In article <[e-mail]>, [e-mail] (Ron Baalke) writes:
|> " Fanson said. "We are
|> talking about very small motions -- the total stroke of the
|> actuators is equal to the length your hair grows in 15 minutes."


Arrggghhhh!  this gets worse. This is actually rather interesting,
anyone got any real numbers?  Perhaps I could work it out, but
it doesn't say whose hair, where on the body or whether it is is
summer or winter, or indeed whether it is an African or European
swallow :-)

                    Francis Vaughan.

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

Date: Mon, 15 Mar 1993 02:04:34 GMT
From: Dave Hayes <[e-mail]>
Subject: cancel wars accountability
Newsgroups: comp.org.eff.talk,alt.privacy,sci.space,sci.astro,news.admin.policy

[e-mail] (Jay Maynard) writes:
>>>I'll say it again: YOU, SIR, ARE A COWARD!
>>The real cowards hide behind the popular sentiment.
>That would make me a coward if and only if my view was the popular sentiment.

I didn't say you were a coward. Are we being...Defensive?

>In this case, since I fully support Dick Depew's approach, that's definitely
>not the case.

So you support auto cancel daemons, eh? Figures.
--
Dave Hayes - Network & Communications Engineering - JPL / NASA - Pasadena CA
[e-mail]       [e-mail]         ...usc!elroy!dxh

  Counterfeiters exist because there is such a thing as real money.

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

Date: Mon, 15 Mar 1993 02:08:41 GMT
From: Dave Hayes <[e-mail]>
Subject: cancel wars accountability
Newsgroups: comp.org.eff.talk,alt.privacy,sci.space,sci.astro,news.admin.policy

[e-mail] (Jan Isley) writes:
>>NO! Reveal his identity now and many knee jerks will forever condemn him/her.
>>I think the person has sucessfully demonstrated a few foibles in people and
>>now these people want to crucify. Why not learn from the mistakes and leave
>>the issue alone?
>It is not a foible to expect one to be accountable for one's actions, it
>is reasonable, adult behavior.

But it is. Why should you expect _anything_ from anyone else? Why should you
expect that <random authority on subject X> is always right or <random
infamous dweeb> is always wrong?

>One would think that Dave would have some
>personal insight about getting crucified for grossly irresponsible news
>admin behavior.  It appears that Dave has learned nothing from his mistakes.

The insight was valuable indeed. Crucifixion has (obviously) not changed
my point of view to "comply" with "established and proper modes of thought".
I _have_ learned many things about human behavior...such as the obvious
personal attack when one is wanting to win a debate.
--
Dave Hayes - Network & Communications Engineering - JPL / NASA - Pasadena CA
[e-mail]       [e-mail]         ...usc!elroy!dxh

Intellectual (n.) - 1. One who knows no craft

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

Date: Sun, 14 Mar 1993 21:20:55 GMT
From: "John S. Neff" <[e-mail]>
Subject: Charon: Planet or moon?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Arthur Chandler) writes:
>From: [e-mail] (Arthur Chandler)
>Subject: Charon: Planet or moon?
>Date: Sun, 14 Mar 1993 00:26:54 GMT
>>
Is Charon a moon or a coplanet of Pluto?  And what, if any, are the
>formal distinctions between the two categories?  And finally, is there
>any minimum size for a body to be considered a moon, and not just
>orbiting debris?  In other words, would you call a 2-centimenter rock
>revolving around a planet a moon of that planet?

There is no agreement among astronomers as to the formal definition of a
planet. In particular Pluto is called a minor planet by some astronomers
and a major planet by others.

If Pluto is a minor planet it is the largest minor planet, and so far the
only one that we know for certain is a binary. Although there is
credible evidence that other binary minor planets exist.

If Pluto is a major planet it is the smallest in radius and mass. From
these properties we can infer the internal structure of Pluto which turns
out to be similar to the moons of the outer planets.

If Pluto is a binary satellite it would be the only known example in the
solar system.

It is likely that this argument will last a long time.


I think most people would agree that a  2 cm diameter object would not
be called a moon. The smallest satellite listed in Astrophysical Data:
Planets and Stars. by K.R. Lang, Springer-Verlag is J13 Leda at ~5 km. M2
Deimos is 8 x 6 km a moon Mars is the next smallest.

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

Date: Tue, 9 Mar 1993 02:39:02 GMT
From: Jonathan Stone <[e-mail]>
Subject: Huygens will float....
Newsgroups: sci.space,alt.sci.planetary

> [...] the probe
>would float deep enough such that the refractive index sensor would
>be fully immersed, but high enough so that the Descent Imager/Specral
>radiometer is above the waterline.
                         ^^^^^^^^^^

Is there is a generally-accepted planetary-science generic term
analogous  to ``waterline'', but for liquids that aren't H20.
Is ``waterline'' that term, and if not, what is it?    And do we
already know enough about Titan's atmospheric composition and surface
temperature to engineer a probe that will float in  all plausible
Titanian surface liquids?   If not, what *will* Hugyens float in?
Liquid ammonia??


In case it isn't clear, these are genuine questions, not
sarcasm or pedantic second-guessing of JPL...

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

Date: Sun, 14 Mar 1993 20:35:56 GMT
From: Dave Tholen <[e-mail]>
Subject: Planet X
Newsgroups: sci.space

Claudio Egalon writes:

> I do not know if it is right place to post an article like that but let us
> give a try...
>
> Sometime ago I read an article in Sky and Telescopy about the discoverer of
> Pluto, Clyde W. Tombaugh (may be I have mispelled his name). He contended
> that, based in his earlier work and from gravitational data from the Pioneers
> and Voyagers spacecraft, there was NO planet beyond Pluto  however he did nt
> came forward with an explanation for the perturbation in the orbits of Uranus
> and Neptune! So here you are, certain astronomers, in order to explain
> deviations in the orbits of these two planets, postulate the existence of a
> 10th, yet undetectable, planet in the solar System and comes Pluto's
> discoverer and say that there is no 10th planet but does not offer any
> explanation of the orbit deviation of the other planets. How
> come??? Is there anyone in the NET who can explain Tombaugh's position???

Two comments are in order.  First of all, during his search for Pluto,
Tombaugh examined a huge amount of the sky.  He maintains that if a tenth
planet was out there, he would have seen it.  Of course, that would be
true only if the planet were bright enough to have been picked up on his
plates, so that does constrain things.  Also, Tombaugh looked primarily
along the ecliptic, so any objects substantially off the ecliptic could
have been missed.

Second, a lot of astronomers simply don't trust the veracity of the
observations of Uranus and Neptune from the 19th century, which are the
ones showing the systematic residuals.  Throw them out, and their is no
unexplained deviation any more.  Other astronomers believe those old
observations.  Who's to say?

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

Date: Mon, 15 Mar 1993 01:37:23 GMT
From: Henry Spencer <[e-mail]>
Subject: Planet X
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (CLAUDIO OLIVEIRA EGALON) writes:
>Clyde W. Tombaugh ... contended that, based in
>his earlier work and from gravitational data from the Pioneers and Voyagers
>spacecraft, there was NO planet beyond Pluto  howeverJhe did not came forward
>with an explanation for the perturbation in the orbits of Uranus and Neptune!
>...Is there anyone in the NET who can explain Tombaugh's position???

The problem is that the best evaluation of the orbits of Uranus and Neptune,
based on the best observations (the 20th-century ones), says that there is
*no* unexplained error in their positions.

Unfortunately, if you use earlier data, problems do crop up.  There is
enough historical data of reasonable quality to raise a good possibility
of a perturbing force in the past.  But then why has it gone away?

Any proposal for a tenth planet also has to explain some other major
bits of negative evidence.  There is no unexplained perturbation in the
trajectories of Pioneers 10 and 11 and the Voyagers, and their positions
can be measured far more accurately than those of the planets.  Tombaugh's
sky search, which was good enough to find an insignificant little speck
like Pluto, should have spotted any major planet unless it was a long
way out or far away from the ecliptic.  IRAS didn't find anything either,
looking in wavelengths where a gas giant ought to be much more prominent
than in visible light.

None of these things rules out a tenth planet, but it's difficult to make
it consistent with all the evidence unless it's in a really strange orbit,
which would itself require considerable explaining.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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

Date: 14 Mar 93 10:21:39 GMT
From: Pat <[e-mail]>
Subject: Retraining at NASA
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Brian Donnell) writes:
>Major sigh...I think most of us within NASA who read these
>threads look at them with a sense of resignation. People
>like Nick Szabo and Tom McWilliams are so misinformed,
>it's depressing to even attempt to correct them.
>

Nothing like postnews to try and clear the air.   We really would
welcome some honest input from the folks at NASA and the contractor
community on what is going on.

>But let me be absolutely clear from the beginning.
>I think it *is* NASA's fault that they are misinformed.
>NASA's PR in general has been pathetic (until very
>recently). JPL, for example, has great PR, and that's

That is the Problem,  too much PR, and not enough news.
It's interesting to read the Press releases and mission statements,
but what is more interesting is the debate, the weighing of priorities,
the merits and meanings of particular events.

Press releases  have a way of blurring the impact of events until a certain
spin has been placed upon it.  What would be nice is to see people
posting on what they think certain things mean.

When JPL approves a mission, with N intruments aboard, it owuld be nice
to know what was left out,  and what that impact was  or why  devices
a,b and c  were chosen in the architecture.

When what we get from NASA  is mostly a snow job of press releases,
and a continous stream of it's all okay and we are all one happy family,
then why should we believe what we hear?



>why people like Tom realize they do great work (and they
>*do* in fact do great work). However, the other elements
>of NASA are also just as productive and capable. And the
>counter-example is true - there are several major flubs
>on JPL's record too.
>
We all make mistakes.  the trick is to have more wins then losses.

>I do not pretend to claim that there haven't been any
>mistakes in the design and implementation of NASA
>programs, for there have been many. But that is the

But all we hear is the covering and obfuscation leading up to
these.

>nature of things when you are doing things for the
>first time - and I sometimes think people forget that's

Everything is a first time for someone,  it's aquestion of how
much new engineering  versus  old engineering will be done.

>what we're doing. I would further argue that no
>collection of private consortiums could have done *any*
>better with the given resources.  I know this is a

Possible.  especially, if they bought into the same number of institutional
sacred cows.

>badly bruised and beaten horse, but the fact of the
>matter is that the lack of vision in Congress has been
>a major contributing factor to many of NASA's difficulties.

Lack ov vision of every president since johnson, you mean.
It has been republican presidents who have not gone to task to
get the levels of fundings.  When DOD  can get  1 trillion dollar
5 year budgets,  it is not hard to get NASA a 60 billion dollar
5 year budget allocation.

The fact is the president has not wanted to spend the energy to
do so.  Nor has any president had a strategic vision for NASA.

Of course it's hard to have a strategic vision when 50% of all effort is
devoted to maintaining a center and it's contractor community.

>Most (if not all) of the frustrating shortcomings in Shuttle
>and Station are due to inadequate, unrealistic and
>fickle funding.  The technological know-how within NASA

Sorta " there is never enough 'TIME/MONEY' to do things right,
    but there is always 'TIME/MONEY' to do things over"

It is a aspect of honest engineering to say that something
cannot be achieved with the resources.



>is there.  The bureaucracy of government procurement
>forced on NASA is another stumbling block.  If Congress

No more difficult then that of other agencies.  SDI has to cope with
this.  DOE has to cope,  DOD has to cope.  NIH has to cope.

>could find the wherewithal to commit to a multi-year
>project, we might have had Station years ago.
>

Ignoring the fact that the initial SSF designs couldn't have been flown
on shuttle, and couldn't hav ebeen maintained once they got there.
And it looks like the EVA might have meant they never got built.

>Brian Donnell
>NASA/Johnson Space Center
>
>on temporary assignment to:
>
>NASA/Ames Research Center

If you don't like what you see, join the debate, otherwise get out of the
kitchen.

pat

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

Date: 11 Mar 93 11:39:38 PST
From: [e-mail]
Subject: Russians ICBMs -> SLVs
Newsgroups: sci.space

Moscow to Launch Start I Missile Carriers
Moscow INTERFAX in [approximate] English
1822 GMT 2 March 1993 via KYODO
Reported in FBIS-SOV-93-040, pp.34&35

     Russia will conduct the first launch March 25 of new "Start-1"
missile carriers, created on the basis of the CC-20 and CC-25
[should be SS-20 and SS-25, but somebody forgot to transliterate
the Cyrillic "C" into the Latin "S"] ballistic missile mobile
complex, and able to launch 550 kg of payload into orbit to
altitudes of 700 km.

     The missile, which Motorola, one of the largest American
communications companies has expressed interest in, is designed to
launch satellites into low orbits for government organizations and
commercial structures to establish satellite communications
systems, distance probing [i.e. remote sensing], and ecological
control [monitoring].

     The "Start-1" missile carrier, to be launched from the
Plesetsk (northern Russia) aerospace field will carry an
experimental communications satellite developed by the Russian
stock company IBK and the Kompleks scientific center.

     Russian military aerospace forces, which launch all rockets in
Russia, will put 5 satellites into orbit in March from the Plesetsk
and Baykonur (Kazakhstan) aerospace fields.

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

Date: 14 Mar 1993 14:56:58 -0500
From: Pat <[e-mail]>
Subject: Sisters of Mars Observer (was Re: Refueling in orbit)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Steve Collins) writes:
|
|i]
|The MO spares are already being rummaged through for use on other missions.
|MESUR is looking hard at the possibility of using some of our AACS hardware
|and I believe that some components are already assigned to other projects.
|I understand that Magellen used a fair number of Galileo spares in this way.
|Steve Collins MO SCT (AACS)


I thought MO was supposed to be one in a whole series of spacecraft?
pat

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

Date: Mon, 15 Mar 1993 01:39:59 GMT
From: Henry Spencer <[e-mail]>
Subject: Sisters of Mars Observer (was Re: Refueling in orbit)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Pat) writes:
>|The MO spares are already being rummaged through for use on other missions.
>
>I thought MO was supposed to be one in a whole series of spacecraft?

The key word is "was".  The Observer series is dead, a victim of
overenthusiasm and overoptimisation on the very first mission, which
overran the original budget and schedule ideas so badly that nobody is
going to try again.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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

Date: Sun, 14 Mar 1993 21:54:11 GMT
From: Jeff Bytof <[e-mail]>
Subject: Tech-Life in the Galaxy
Newsgroups: sci.space

>From: [e-mail] (Josh Hopkins):

>Care to tell us where the number came from?  It would seem to require an
>understanding of the industrial capacity and population of the galaxy.

Just a rough guess, like everything else in the SETI business.

>N in the Drake equation is the number of civilizations in the galaxy.  This
>concept does not increase N, it just increases the probability that two of
>those civilizations will be aware of each other.

It shouldn't matter to our SETI what the source of the intelligent
transmission is, and N by any other definition is the number of SITES
that eminate evidence of extraterrestrial intelligence, regardless
if it happens to be currently "occupied" or not!

-rabjab

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

Date: 14 Mar 93 17:36:46 GMT
From: Lucio de Re <[e-mail]>
Subject: The courage of anonymity
Newsgroups: comp.org.eff.talk,sci.space,alt.privacy

[e-mail] (Dave Hayes) writes:

>[e-mail] (Melinda Shore) writes:
>>example, from experience I know that I can pretty much
>>throw out anything that Masataka Ohta has to say about
>>shared libraries, that Clayton Cramer has to say about
>>gay men, or that Robert Sheaffer has to say about feminism.

>Who are these people, anyway?

Why do you need to ask?

>>That doesn't mean that they don't have anything valid to
>>say on other topics.

>And, of course, that means that they cannot change...in terms
>of your conception of their viewpoint. This is because you
>"know that you can pretty much throw out anything" that they say.

I think I'll have to find a copy of Ted Kaldis (blessed be his name)'s
collected writings, to justify his residence in innumerable kill files.

Sure, he can change his leopard's spots, but is that so important?  Or
are you of the religious view that a repented sinner is more significant
than a permanently good person?

>You have touched on one of the most telling problems of netters.
>They encorage people to hold to unworkable ideas by establishing
>reputations. You lose yours by contradicting yourself or providing

Not at all, unless you're by nature the type of rebel that insists
on swimming against the stream and thus can be readily manipulated

by ostensibly pushing you in the inverse direction...

>fallacious arguments, even if those are as the result of something
>new that you learned. This is how people get stuck in their own desire to
>be perceived as "right" by the net (in order to maintain their
>'reputation')...instead of learning from their own mistakes or by
>intelligent discourse.

Why should anybody get so caught?  Ever seen an apology on the net, or
just a word of thanks for having had an opinion corrected?

>>stand behind it.  I'm all for allowing people to continue
>>to post things like "ALL FAGS GET AIDS AND DIE," but I'd
>>really like to see a name associated with those posts.

>But _why_? If this sentiment is something you disagree with (I'm
>assuming), then why do you care who said it? What could you possibly
>do with that information that would benefit anybody?

Nothing to do with _me_ (or Melinda) knowing who it was.  It's just
that it is far too easy to voice such an opinion when nobody has a
clue as to who you are.  In practice, we all exercise good manners
(as opposed to obeying laws) because we care for our reputation,
knowing that a bad reputation has social repercussions.  Anonimity
removes this constraint (not entirely, of course) and allows a boorishness
to be displayed that would not normally be countenanced.  The Net is
already pretty burdened, it does not need friction to be generated
purely on the strength of being able to dodge any consequences.

Hope I have not been too obscure...
--
Lucio de Re ([e-mail]) - tab stops at four.

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

Date: Sun, 14 Mar 1993 22:10:40 GMT
From: "Eric H. Taylor" <[e-mail]>
Subject: Venus and Mars, was Re: TIME HAS INERTIA
Newsgroups: sci.physics,sci.space

In article <[e-mail]> [e-mail] (Alexander Abian) writes:
>[...]
>VENUS should be given an near Earth like orbit to become a Born Again Earth

Many have been going on about his time has inertia thing, but this
statement seems much more likely a candidate for dumb idea.

I don't have a reference (maybe SciAm), but I heard a while back that
analysis of Venus' atmosphere estimated that Venus has 1/8000 the water
that Earth has. *IF* Venus was moved to a near Earth orbit, its runaway
greenhouse would still have ridiculously high temperatures. Better, would
be to swap Venus with Mars. Photos of Mars clearly show evidence for liquid
water in the past. Speculation has it that there may be large amounts
of water locked into permafrost. If Venus and Mars were exchanged,
Then, Venus might cool off, and Mars could warm up. Possibly, Mars
would then become quickly habitable, but Venus would have a permanent
shortage of water, and thereby could never be a born again earth without
massive importation of water, possibly from asteroids, jovian moons,
or commets.

This thread really is a question of terraforming, and so I set
followups to sci.space. If that is not appropriate, I apologize.

----
 ET   "A Force of Nature"
----

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

End of Space Digest Volume 16 : Issue 314
------------------------------