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Date: Sun, 13 May 90 01:39:48 -0400 (EDT)
Subject: SPACE Digest V11 #394

SPACE Digest                                     Volume 11 : Issue 394

Today's Topics:
	 Saturn's rings on Venus (was Re: Terraforming Venus)
	Re: Terraforming Venus (was: Manned mission to Venus)
	Re: Terraforming Venus (was: Manned mission to Venus)
	Re: Terraforming Venus (was: Manned mission to Venus)
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Date: 13 May 90 02:35:24 GMT
From: thorin!homer.cs.unc.edu!leech@mcnc.org
Subject: Saturn's rings on Venus (was Re: Terraforming Venus)

Mark Bradford writes:
>Just did this calculation (roughly) for my planetary science class.
>Assuming pure water (density = 1g/cm^3), Saturn's rings weigh on the order
>of 4 x 10^19 kg, which is around .003 of Pluto's mass (7 x 10^-6 Earth
>masses).

    To answer the original poster's question, this is a significant
amout of water.  About 70m covering Venus' surface if I didn't drop
some exponents with dc.  But then what do you get?  At best, sort of
like Florida in the summertime, except worse.  And gravity.  Ick.

    Personally, I'd rather see Venus dismantled ala L.	Neil Smith's
_The Venus Belt_, and used to build space colonies in polar orbit
about Saturn so we can appreciate the view.
--
    Jon Leech (leech@cs.unc.edu)    __@/
UNDERWHELMING OFFER OF THE MONTH:
    "Please feel free to skip the payment on this month's statement.
     Normal finance charges will apply." - NCNB VISA

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Date: 12 May 90 01:33:18 GMT
From: usc!samsung!umich!ox.com!kitenet!russ@ucsd.edu  (Russ Cage)
Subject: Re: Terraforming Venus (was: Manned mission to Venus)

In article <44689@iuvax.cs.indiana.edu> hagerp@iuvax.cs.indiana.edu (Paul Hager) writes:
>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?

I believe that about 2 of the 90 atmospheres of pressure is from
nitrogen.  This leaves 88 bars of CO2.  If you remove 12/44 of
that, you've got 64 bars of oxygen, or 66 bars total pressure.
This is an unlivable amount, not to mention an extreme fire hazard.

> 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.

Eliminating the *oxygen* is the real problem, as you can see.
The surface rocks of Venus are believed to be fully oxidized,
so there is no ready oxygen sink available.
-- 
			  Oversimplification doesn't solve problems, it just
(313) 662-4147		  changes them into less tractable problems.
Russ Cage, Robust Software Inc.            russ@m-net.ann-arbor.mi.us

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

Date: 12 May 90 15:57:50 GMT
From: usc!cs.utexas.edu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!physics.utoronto.ca!neufeld@ucsd.edu  (Christopher Neufeld)
Subject: Re: Terraforming Venus (was: Manned mission to Venus)

In article <1990May11.230607.14328@helios.physics.utoronto.ca> neufeld@physics.utoronto.ca (Christopher Neufeld) writes:
>   Each 100km diameter comet would put about 1mm of water over the
>surface of Venus, if spread uniformly.

   I was corrected in e-mail. Make that 1 metre of water.


-- 
 Christopher Neufeld....Just a graduate student  |  "Spock, comment?"
 neufeld@helios.physics.utoronto.ca              |  "Very bad poetry
 cneufeld@pro-generic.cts.com          Ad astra! | captain."
 "Don't edit reality for the sake of simplicity" |

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

Date: 13 May 90 01:31:53 GMT
From: thorin!homer!leech@mcnc.org  (Jonathan Leech)
Subject: Re: Terraforming Venus (was: Manned mission to Venus)

In article <1990May12.221636.10496@utzoo.uucp> henry@utzoo.uucp (Henry Spencer) writes:
>*Nobody* knows the bulk composition of any asteroid for sure.	The best
>information we have is some very general spectroscopic data about the
>composition of the outermost millimeter or so, plus analyses of meteorites
>whose history and origin are ill-documented at best.

    Plus radar observations of Ostro et al.
--
    Jon Leech (leech@cs.unc.edu)    __@/
    "I met a wonderful new man. He's fictional, but you can't have everything."
	- Cecelia, _The Purple Rose of Cairo_

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End of SPACE Digest V11 #394
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