Meteorites point to big chill on ancient Mars (moved from ATSNN)

A study of the gas in meteorites suggests that Mars was bitter cold for much of the past 4 billion years. During this period Mars didn't have any extended wet periods in which life could have lived. The only opportunity for life would be the first 500 million years of it's existence.



I think its sad that scientists say that life more than likely couldn't have lived on Mars in the past 4 billion years. It does say however that it doesn't rule out the possibility of life on Mars, but that biology's best chance for life would be the first 500 million years of it's 4.5 billion year existence


[edit on 7/21/2005 by 9890]

from the last paragraph of the linked story

One of the rocks in the study was the infamous ALH84001, which contains etchings that some scientists have interpreted as being created by microscopic life forms. Shuster said the rock could not have been above freezing for more than a million years during the past 3.5 billion years.

I'm sure someone has told me at some point (I've been to conferences where this was presented & discussed), but how do these guys know this rock came from Mars? And how do they know that the parts they were studying contaminated while they were on the earth. I wish MSNBC and the rest of the popular media would delve a bit more deeply on this kind of stuff.