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Iceland Discovery Promotes Martian Life Hypotheses
nusratt writes "This nature.com article reports research presented at the Bioastronomy 2004 conference in Reykjavik, Iceland. 'Scientists have discovered a community of bacteria living in the lake beneath an Icelandic glacier. The chilly world provides a model of Martian terrain and may boost speculation about the red planet's potential inhabitants. This is the first unequivocal example of life in a subglacial lake. The bacteria were definitely not introduced from above'."
You know, there's a diffrence between living in such a hostile
environment and evolving there. I hardly think the life living
under harsh conditions in iceland evolved there. It rather gradually adapted from things living under much 'friendlier' conditions.
Conditions that might never have been present at Mars, allowing life to
start at all.
In fact, the high temperatures on re-entry for meteorites are over-blown. Only the surface of the rock gets hot, the interior can still be very cold. Rock is a pretty good thermal insulator. Think about it. If you put a 5lb rock into a white hot oven - and took it out again 30 seconds later, the middle would still be cold. It doesn't take many seconds for something at 50 times the speed of sound to travel through a few miles of atmosphere.
Also the outer layers of the rock (which DO get hot) tend to boil away, carrying the heat away in just the way that the heat shields on spacecraft (other than the shuttle) are designed to do.
Critters riding (frozen) in the center of the rock might well thaw out quite gently long after they hit the ground.
Hence, a robust space travelling bug would only need to be able to recover from beeing deeply frozen - it wouldn't have to be able to cope with high temperatures at any point in its journey.
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