Re:Mars methane discovery hints at presence of life
by thamer on Friday January 16, 2009 @05:32AM
(#436420)
Well, the Earth itself has been transformed by life! Most of the oxygen in the atmosphere comes from billions of years of photosynthesis:
- http://en.wikipedia.org/wiki/History_of_Earth#Photosynthesis...
- http://en.wikipedia.org/wiki/Earth%27s_atmosphere#Evolution_...
Re:Mars methane discovery hints at presence of life
by rbanffy on Friday January 16, 2009 @07:47AM
(#436532)
Most probably, a big chunk of the oxygen in the atmosphere comes from last month's photosynthesis - we use it to make CO2 and green stuff converts it back, so, it's always brand-new oxygen we see. But free oxygen indicates a far more active biosphere than lots of methane would and I get your point - methane makers are much lower profile than oxygen makers.
As for Titan being covered with life... We really don't know if the lakes we see from space aren't giant amoebas waiting patiently to eat any humans that land on their beaches and just cleverly pretending to be lakes. ;-)
If there is some life there, it must be either very efficient in generating methane or very good at hiding itself ;-)