Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V11_3/V11_390.TXT

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Subject: SPACE Digest V11 #390

SPACE Digest                                     Volume 11 : Issue 390

Today's Topics:
    Re: Terraforming Venus (was: Manned mission to Venus)
    Re: Terraforming Venus (was: Manned mission to Venus)
               Re: why there are no ETs
            Re: Terraforming Venus
    Re: Terraforming Venus (was: Manned mission to Venus)
        Re: Venus and Mars and Asteroids O MY!
                 Re: PegBlimp
            The Vatican Connection
               First Light HST pictures
              Re: National Space Society
----------------------------------------------------------------------

Date: 12 May 90 03:06:07 GMT
From: news-server.csri.toronto.edu!helios.physics.utoronto.ca!physics.utoronto.ca![e-mail]  (Christopher Neufeld)
Subject: Re: Terraforming Venus (was: Manned mission to Venus)

In article <[e-mail]> [e-mail] (Dan Tilque) writes:
>
>A lot of people have been suggesting getting water from planetary rings
>or satellites for Venus.  I think a better source would be to get
>comets.  To get them you'd have to go out to the Kuiper Belt/Oort
>Cloud, find them, change their orbit, wait for them to fall a ways,
>correct the orbit, etc.
>
   I think it would be more practical to catch a comet which was already
penetrating into the inner solar system, knowing when and where it would
return based on previous observations. I don't know exactly how far out
the Oort cloud is believed to be, but the number that sticks in mind is
some 0.5 to 1.5 light years. Now, if you cancelled all the orbital
velocity of a given comet at 0.5 light years out, it would fall into the
inner solar system in about one million years. By then you'd probably
have been able to terraform Venus by sending people there one by one and
having them spit on the planet.

>This would require a lot of comets, because you'd want Venus to have
>about as much water as Earth does just to ameliorate the climate (there
>goes most of that real estate, under the new oceans).  However, if you
>got the comets to impact correctly, you could speed up Venus' rotation
>somewhat (not by much though).  The impacts may also remove some excess
>CO2 for you too.
>
   Each 100km diameter comet would put about 1mm of water over the
surface of Venus, if spread uniformly. Speeding the rotation noticeably
is pretty well out of the question. A comet that size probably comes
along only once in a century, even if you look for comets with very
large apehelia.
   As for removing CO2, there is a section on Venus' atmosphere in that
reference I dug up a couple of months ago. It mentions that the presence
of liquid water on the surface of the planet would catalyze a reaction
involving common surface rocks called pyroxenes which could soak up most
of the CO2 over a time span measured in hundreds of years. The big
problem is accumulating liquid water on the surface.

>Of course, there's probably better things to do with comets than dump
>them on Venus.
>
   It would take a lot of effort to consume even one 10km comet for
water, reaction mass, fusion fuel, oxygen distillation, or whatever. A
comet that size, if it were pure water, would contain 520 billion tons
of water.


--
 Christopher Neufeld....Just a graduate student  |  "Spock, comment?"
 [e-mail]              |  "Very bad poetry
 [e-mail]          Ad astra! | captain."
 "Don't edit reality for the sake of simplicity" |

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

Date: 11 May 90 15:43:33 GMT
From: clyde.concordia.ca!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Terraforming Venus (was: Manned mission to Venus)

In article <[e-mail]> [e-mail] (Lord Snooty @ The Giant Poisoned Electric Head       ) writes:
>In "A Step Farther Out" by Jerry Pournelle (many years old now) he advocates
>using blue-green algae dropped in massive clouds from above. He assumes that
>these will gradually cause rain to precipitate rainstorms, which will
>slowly descend through the Venusian atmosphere, will eventually hit the
>ground and thereby cool it.
>
>Anyone read this and/or could comment?

This idea was proposed in the late 60s by some of the planetary astronomers.
Knowledge of conditions on Venus has improved quite a bit since then.  It's
worse than anyone thought.  The algae won't work, alas.
--
Life is too short to spend    |     Henry Spencer at U of Toronto Zoology
debugging Intel parts. -Van J.| uunet!attcan!utzoo!henry [e-mail]

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

Date: 11 May 90 15:33:40 GMT
From: swrinde!zaphod.mps.ohio-state.edu!rpi!uupsi!grebyn![e-mail]  (Pat Bahn)
Subject: Re: why there are no ETs

I think the problem is humans don't understand probability.....

everyone says if only 1% of all stars could sustain life and 1% of those
develope life  and 1% is intelligent and 1% technical and 1%goes
starfaring..... it would still be gazillions of civilizations.


well  first of all the Universe is real big....  Bigger then we know,
second you are all postulating FTL drive,  may not be possible if so
then one can only trvel at best .3c without wiping out star systems in
energy demands....

given those realistic constrainst Inter-galactic travel is out.

Interstellar becomes multi year even century based activities, hell we
dont fund space exploration like we should, what assumes zorkon's are
any different.

    we are in a back-water,  way out in one spiral am, in a
relativley sparse part of the galaxy.  If I was a zorkon, i'd send
probes inward,  much better science return

    finally we are relatively new on the scene.  If the zorks are
broadcasting heavy metal, if they are on the other arm of the galaxy
were talking 100,000 years for us to hear ozzie zorkon and the tentacle
slammers.....

    relaistically, I think it would be 2-3 millenia of maintaining
a technical civilization to have a chance of an encounter.

also what is the probablity that a technical civilization doesn't
blowthemselves up, poison themselves or otherwise get still-born.

it may be that most civilizations don't have a good chance of achieving
light-speed travel without killingthemselves.  look at the romans and
lead.  We still don't understand roman science and engineering.

heck allwe need is few good chernobyls and we could put ourselves back
40-50 years.  That or I still have odubts about my water supply.

well sorry about the spelling, but this is a bad line.  I just think
it's the odds of the uniiverse, and it is a real bitch
--
=============================================================================
Pat @ grebyn.com  | If the human mind was simple enough to understand,
301-948-8142      | We'd be too simple to understand it. -Emerson Pugh
=============================================================================

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

Date: 11 May 90 00:51:38 GMT
From: bfmny0![e-mail]  (Tom Neff)
Subject: Re: Terraforming Venus

If we seed Venus' atmosphere with blue-green algae, Venus would sure
be pretty as a morning or evening star wouldn't it?!

But what tackles the H2SO4?

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

Date: 11 May 90 18:11:16 GMT
From: [e-mail]  (Paul Hager)
Subject: Re: Terraforming Venus (was: Manned mission to Venus)

[e-mail] (Lord Snooty @ The Giant Poisoned Electric Head) writes:

]In "A Step Farther Out" by Jerry Pournelle (many years old now) he advocates
]using blue-green algae dropped in massive clouds from above. He assumes that
]these will gradually cause rain to precipitate rainstorms, which will
]slowly descend through the Venusian atmosphere, will eventually hit the
]ground and thereby cool it.

]Anyone read this and/or could comment?

I think I heard/read it from Carl Sagan first.  Using bio-engineering
is clearly the best way to proceed because once you introduce your
bugs, they'll self-replicate as long as they find a favorable
environment.  It would probably be necessary to "evolve" a whole
series of bugs that would make successive alterations in the
"ecosphere".

When I first heard the idea, I think the paucity of H2O in the
atmosphere was not known.  How much hydrogen is available (isn't
there H2SO4 in the atmosphere?) is something I don't know but
that would seem to be a serious problem.  Also, I don't know
the quantity of nitrogenous compounds present.  I wouldn't think
that it would be possible to bio-engineer the Venusian atmosphere
down to pure oxygen (for obvious reasons) -- does anyone know
offhand what the atmospheric pressure would be if all of the
CO2 were converted to O2?  My guess is that it would be necessary
to react a lot of the O2 with native minerals to get it out of the
atmosphere.  This means that the carbon that our bugs precipitate
out has to be "buried" somehow lest it react with the O2 and
re-enter the atmosphere, rendering the whole project a Sisyphean
nightmare.

Mind you -- I'm gung ho to see the project get going.  What a boon
for the micro-biologists, planetologists, ecologists, chemists, and
last (but not least) the space scientists.  It would be a great
test bed for developing technologies for planetary engineering and
the spin-offs alone should pay for the R&D investment.  Still, I
think that the optimistic time frame for going from a CO2 shrouded
hell to planet girdling tropical rain forests has to be several
centuries, at least.


--
paul hager        [e-mail]

"I would give the Devil benefit of the law for my own safety's sake."
                       --from _A_Man_for_All_Seasons_ by Robert Bolt

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

Date: 11 May 90 19:41:03 GMT
From: mcrware![e-mail]  (James Jones)
Subject: Re: Venus and Mars and Asteroids O MY!

In article <[e-mail]> [e-mail] (Fraering
Philip) writes:
>If we make the program mainly a spectator sport, it will fail. Football
>is cheaper.

Having come from Enormous State University, as Tank McNamara puts it, I've
often wondered whether the thing to do to get a space colony would be to go
to the ESU Alumni and say "you know, <fill in name of player> could pass/kick
a football N times as far on <fill in name of astronomical body or manmade
space environment> because of the lower gravity."  Sort of displays a benefit
that many people can understand. :-(

    James Jones

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

Date: Fri, 11 May 90 16:43:00 CDT
From: [e-mail]
Subject: Re: PegBlimp

> bfmny0![e-mail]  (Tom Neff)

> What about launching Pegasus from a dirigible?
>
> OK, you don't get as many initial MPH as from a Buff,

I (vaguely) recall reading somewhere a few years ago about someone
discussing the design of a semi-rigid airship which would be capable
of high (Mach 1+ ?)  speeds as well as lifting large loads.  The
article was something to do with replacing airliners with something
ecologically more sound or something like that.

Has anyone else ever heard of anything like this?

[I'm not at all sure of this any more.  It *was* quite some time
ago.]

==============================================================================
| Fred McCall  ([e-mail]) | "Insisting on perfect safety is for  |
| Advanced Systems Division           |  people who don't have the balls to  |
| Defense Systems & Electronics Group |  live in the real world."            |
| Texas Instruments, Inc.             |                     -- Mary Shafer   |
+-------------------------------------+--------------------------------------+
|  I speak for me.  I don't speak for others, and they don't speak for me.   |
==============================================================================

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

From: [e-mail]
Date: Fri, 11 May 90 18:11:55 EST
To: [e-mail], [e-mail]
Subject: The Vatican Connection
Source-Info:  From (or Sender) name not authenticated.



     Last night (5-10-90) on _Prime Time Live_ there was a story on the
observatory complex that the University of Arizona is planning to build.
Some biologists have said that the project would harm the rare red squirrel
that live there.  The project was temporarily delayed when the Fish and
Wildlife Service placed the squirrel on the endangered species list.  The
university pressured the Arizona delegation to Congress and a variance was
granted.  As soon as the university began building an environmental group
(I believe it was the Audubon Society) successfully filed suit and halted
the project, at least for now.  The suit revealed that some biologists were
pressured into telling Congress that the squirrels would not be in danger.

      The university was able to pressure Congress because of the backers of
the project were quite powerful: the Max Planck Institute, the Smithsonian,
and even the Vatican!  Pope John Paul II even met with university officials
in 1987 to discuss the project.  (And by backing I mean funding.)

     This seems to show a marked change in the Church's attitude toward as
astronomy.  Centuries ago it persecuted Galileo and only made its formal
apology for doing so just a few years ago.  Know the Church is funding
telescopes!  In my opinion, it would suggest that the Church feels that
astronomy is a way towards understanding God better.  Any comments?


                                    David R. Brierley
                                    Northeastern University Geology

                                    [e-mail]

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

Date: 11 May 90 16:54:08 GMT
From: agate!astroplasma.berkeley.edu![e-mail]  (Michael Richmond)
Subject: First Light HST pictures


  Ivan King (one of the scientists involved with HST here) has been kind enough
to post status reports on our department bulletin board. They come from Ron
Polidan, who I hope won't mind if I paraphrase a small portion of his latest
(May 10) message.

  Basically, currently HST images are only focused to about 4 arcsec, which is
why no pictures have been released yet ("We paid $1.5 billion for THIS?!").
There are several stages (called Bootstrap A, B, etc.) in the focusing of
the main instruments - Bootstrap A will bring images down to about 1.5 arcsec.
It is scheduled for Monday, May 14 and Friday, May 18. If all goes well,
one of those test images will be released as "First Light."

  Otherwise, the satellite is getting better and better. Things are generally
looking good.

--                                          Michael Richmond
"This is the heart that broke my finger."   [e-mail]

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

Date: Fri, 11 May 90 15:47:13 CDT
From: [e-mail]
Subject: Re: National Space Society

> agate!agate![e-mail]  (William Baxter)

> In article <[e-mail]> [e-mail] (Craig E. Ward) writes:
>
> >In article <[e-mail]> [e-mail] (Dave Smith) writes:
> >>         The survey, however, is designed to produce specific responses
> >>from the respondent.
>
> >>      As someone pointed out in e-mail to me, every organization needs
> >>sheep.  This is fine.  However, I don't like their agenda as shown to me
> >>from that survey
>
> > You need be careful about judging the whole program from such a narrow slice
> >of information.
>
> There's no need to play dumb, Craig.  The NSS wants sheepish members.

I think Mr. Baxter gets a bit carried away in this statement and in
the rest of his diatribe against the NSS.  The survey in question
reads very much like the 'survey' circulated by the Planetary
Society with regard to a joint U.S./U.S.S.R Mars mission.

I'm inclined to agree that this particular tactic, which appears to
be borrowed from the Planetary Society, doesn't exactly make NSS look
too good to me, either.  However, unlike Mr. Baxter, I'm rather
disinclined to condemn an entire diverse organization, all its
chapters, and all the people in it for doing this.

Unfortunately for those of us who prefer thinking things through on
our own, the 'average American' doesn't appear to agree that that is
the best way to arrive at conclusions.  Hence, questionaires like
those from NSS and Planetary Society are more effective with that
'lay public' than the kind that require real thought.  This problem
is also demonstrated by the kind of negative election campaigns we
see of late, and even by Mr. Baxter's own tactics.

After all, he's not appealing to people with facts; he's playing
polemics.

I've often wondered just what it is that motivates Mr. Baxter (and
another person who should be left unnamed) in what looks from the
outside to be a hysterical hatred of the NSS.

> . . . and they become angry when their letters and articles are refused
> for publication.

I guess that explains it.


==============================================================================
| Fred McCall  ([e-mail]) | "Insisting on perfect safety is for  |
| Advanced Systems Division           |  people who don't have the balls to  |
| Defense Systems & Electronics Group |  live in the real world."            |
| Texas Instruments, Inc.             |                     -- Mary Shafer   |
+-------------------------------------+--------------------------------------+
|  I speak for me.  I don't speak for others, and they don't speak for me.   |
==============================================================================

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

End of SPACE Digest V11 #390
*******************