>
>Keith Knapp wrote to Mark Bloss about Venus
 
 MB> The surface of the Earth was once that hot.  But really now, the
 MB> surface of Venus is really only averaging a temperature closer to
 MB> 450 degrees F.
 KK> I may have misremembered the number.  Are you sure you don't mean 450
 KK> C? 
 I'm sure it's fahrenheit, but I'm sure you mean highest tempurature, not
 mean tempurature.  It stays hot on the surface _all_ the time, but it
 still varies quite a lot.  It definately goes as high as 800, but 
 _averages_ half that.
 KK> At this temperature _now_ certain types of bacteria
 MB> _thrive_ now on Earth in the deep ocean at volcanic vents.
 KK> I recall that those bugs (archaeobacteria) can function at temps
 KK> slightly above boiling.  I'm not sure they can survive at 450 F.
 
 Even in extremely hot spouts bacteria thrives, in places which would
 be toxic waste disaster areas in populated areas - bacteria thrives.
 Nevertheless, there are hot spots, and relatively cold spots, on 
 Venus.  Not even the entire Earth is inhabitable, it is possible
 that not even the entire Venus is _uninhabitable_.
 MB> The earth has, in fact, an oxygen rich atmosphere _because_ early
 MB> bacteria excreted oxygen as a waste product.
 KK> Right.  That's one thing that suggests that either life never got
 KK> started on Venus, or it got started and isn't doing much, or if it
 KK> exists it's very different from life here:  Venus's atmosphere is
 KK> high in CO2 and low in oxygen.
 Not to mention sulfuric acid, mercurium, ferric bisulfide, guanine
 hydroxinase, nitric acid, among other nasties.
       
 Cyanic bacteria which thrives on sulfuric acid took hundreds of millions
 of years to oxygenate the atmosphere of Earth.  There is little evidence
 which would discount the possibility that the same process is taking place
 on Venus _now_.  Simply because we haven't observed a significant 
 change on Venus since we started looking, doesn't demonstrate much
 at all.  It may be 4 or 5 million years before even a small change
 will occur.  Oxygen would provide other changes eventually, such
 as gradual cooling, precisely like that which took place on the Earth 
 about 4 billion years ago.  It would also inhibit the chemical reactions
 on the surface and in the atmosphere of Venus, causing a great deal of 
 oxidation of the various prevelant elements.  This process might take
 1 or 1.5 billion years before a significant change would even be 
 noticable!
 It would be foolhardy to assume that we should wait until there is
 evidence that life exists there, before we go and try to find out
 how life comes "to be".  It is at this time when there seems to be
 no evidence of life, that we ought to be looking very closely for
 it.  Even so, how does one look for something that takes a billion
 years to "happen"?
... Davis' Explanation: Serving coffee on aircraft causes turbulence.
--- GEcho 1.11++TAG 2.7c
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