posted on Dec, 4 2012 @ 02:02 PM
Due to its smaller size, and lesser density, Mars would have cooled sufficiently, after its formation, for life to begin there, while Earth was still
too hot. It's now been realized that Mars early on had surface water and a much denser atmosphere than it has now, probably making it hospitable to
life. There is a good chance that if one planet seeded the other with life, Mars did the seeding and Earth was the recipient.
BTW, when finding organic material on Mars, they should eventually be able to determine if its due to life or not. This was discussed at the press
briefing yesterday. Finding a predominance of the lighter carbon isotope, carbon 12, is diagnostic of life. Living things preferentially use carbon
12, instead of carbon 13.
edit on 4-12-2012 by Ross 54 because: added additional material bearing on the discussion.
on 4-12-2012 by Ross 54 because: added additional material bearing on the discussion.