From: knapp@spot.Colorado.EDU (David Knapp)
Subject: Re: Seeding Mars with life
Organization: University of Colorado, Boulder
Date: Fri, 14 Aug 1992 01:54:12 GMT

In article <9208120143.AA07834@cmr.ncsl.nist.gov> roberts@CMR.NCSL.NIST.GOV (John Roberts) writes:
>
>-From: knapp@spot.Colorado.EDU (David Knapp)
>-Subject: Re: Seeding Mars with life
>-Date: 11 Aug 92 15:38:58 GMT
>-Organization: University of Colorado, Boulder
>
>-In article <20625@sbsvax.cs.uni-sb.de> dietz@cs.rochester.edu writes:
>->Even the "vent" organisms are exploiting the chemical gradient set up
>->by photosynthesis (they oxidize the reduced chemicals coming out of the
>->vents), and are therefore not completely geothermally powered.
>
>-The do not comsume photosythesized materials. (at least according to National
>-Geographic...)
>
>I think the point Paul's trying to make is that the organisms take advantage
>of oxidizing chemicals (perhaps oxygen among them) produced by photosynthetic
>life. I don't know enough on the subject to confirm or deny that. I have
>read that some bacteria get their energy by some chemical change in iron
>compounds, and that others get it by converting one sulfur compound to another,
>and it would be helpful if Paul would comment on whether both of these are
>tied in with compounds produced by photosynthesis.

You say *the* organisms. Perhaps you mean most Earth organisms? I agree. Do
we know that there *isn't* any life for sure on Mars? No. If there were some
type of bacterial or fungal (or new class) of life there, do we know what
effects Earth life would have on it? No, we cannot know that.  Are we 
certain that no life form from Earth could survive *anywhere* on Mars? No,
of course not. We don't even know what 'most' of Mars is even like. With
so many questions unanswered, don't you think it is prudent to proceed with
the utmost caution?


>
>-If we get cocky and think we can forcast everything that might ever happen
>-concerning life on another planet or moon, we could quite easily destroy our
>-ability to detect it or study it.  You might not think that would be a waste,
>-but luckily, NASA and ESA (and many others) do. For the cost of creating a 
>-sterilization policy, we insure a better possiblity of finding life if it
>-exists on Mars.  We've already mucked up this planet enough with ego-
>-centricity, I don't think it's a bad thing at *all* to treat the only other
>-planet in our solar system, which might be able to support humans, with kid 
>-gloves.
>
>If there were some cheap and easy way to get humans to Mars in the near
>future, I'd say we should forget about Mars contamination issues, and go
>for it. However, that does not appear to be the case, so an argument can
>be made in favor of playing it safe with unmanned spacecraft.
>

Depending on what you call 'near future', I agree. But we can also do *that*
with a high degree of decontamination so our studies while we're there are not
possibly hindered by Earth organisms.

We have *much* ground work to do with unmanned craft before that could happen
anyway.



-- 
David Knapp                                      University of Colorado, Boulder
Highly Opinionated, Aging  and                      knapp@spot.colorado.edu
Perpetual Student of Chemistry and Physics.
            Write me for an argument on your favorite subject.