From: amon@elegabalus.cs.qub.ac.uk
Newsgroups: sci.space
Subject: Re: Terraforming
Date: 8 Sep 92 17:25:51 GMT
Article-I.D.: cs.Bu9x3F.F9I.1
Distribution: sci
Organization: [via International Space University]
X-Added: Forwarded by Space Digest
Original-Sender: isu@VACATION.VENARI.CS.CMU.EDU

Mars may not be so difficult to terraform after all, if Dr. Robert  
Zubrin is correct. Two standard large fission plants put to work for  
a decade producing Methane are sufficient to push Mars into a  
"runaway greenhouse" that will very quickly (ie ~ 10 years) lead to a  
1/3 Bar atmosphere of CO2, shirtsleeve temperature range and liquid  
water on the surface.

In a luncheon talk at the recent ISDC he showed graphs which showed  
how Mars fell into a deep freeze a billion or so years ago when it  
hit the upper unstable point. But in the ensuing years, the sun has  
warmed up and the lower unstable point is now within 5F average  
planetary temperature of a runaway back to the original state.

This might even happen on its own if theories are correct about Mars  
going through warm up cycles when its orbital parameters bring it  
into a warmer climactic periond. Zubrin then, is only suggesting we  
hurry it up by a few 100K years.

I warm, wet CO2 atmosphere will lead to rapid spread of plant life.  
(At least plant life that does not require bees & other pollinators!)

This is both a blessing and a problem. If the atmosphere is changed  
from CO2 rich to an O2, it will become transparent and may go back  
into deep freeze. Of course this would all take so many centuries  
that I'm sure it will not be considered difficult to fix by the far  
future descendants who have to deal with it: even the most  
pessimistic among us would have to assume we have full nanotechnology  
within ten or twenty thousand years!! (They may well preserve the  
outer kilometer as a museum of ancient human history and the rest of  
the body for more important uses, like building a Dysan Sphere or  
billions and billions of O'Neill Cylinders.)

This brings up an interesting idea (copyright, all rights reserved)  
what if there is a dormant form of photosynthesizing bacteria on  
Mars? Then, when Mars goes into a warm period, Zubrin's runaway green  
house would occur; followed by massive thaws, as suggested by the  
presence of flood outflow channels on the Martian surface; the native  
"plant" life would bloom hysterically. It would shift the atmosphere  
towards greater transparency and as Mars continued to precess away  
from the warm max, it would fall back into the runaway deep-freeze  
and kill of the plantlife... I can account for the lack of  
unambiguously positive findings by Viking by the sterilizing effects  
of heavy surface UV over the large interrignum between thaws. No real  
evidence for the idea, but if true it would suggest that there would  
be dormant cells in stable, out of the way, well protected places.  
And for the uninitiated, yes, cells (on Earth) have been found to be  
viable after thousands of years of dormancy.

I have hopes that Ad Astra will publish a popular account of Zubrin's  
work. I think their Mars special issue will be due out soon...
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