Scientists Unsure if Methane at Mars Points to Biology or Geology

A trio of research teams independently probing the Martian atmosphere for signs of methane have found it, a combined discovery that opens the door for a host of theories as to how the gas got there.

Among the most tantalizing, if not very likely, of scenarios, scientists say, is the possibility that the Mars methane could be the byproduct of some form of microbial life. But a safer bet, they say, centers on the geology of Mars, including anything from volcanic activity to long-ago impacts of methane-carrying comets.

"It's of course very exciting and quite a surprise," said Augustin Chicarro, project scientist for the European Mars Express mission, which detected Mars methane while orbiting the planet. "Mars seems to be a planet that is always surprising us, one week it's an ocean…now this."

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http://a52.g.akamaitech.net/f/52/827/1d/www.space.com/images/030827_hubble_mars_1_01,0.jpg

http://www.space.com/scienceastronomy/mars_methane_040329.html

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I don't understand why the methane story has gotten so little attention compared to the hematite story. Or why biological origin is considered so improbable. Mars is no longer very active volanically, and the methane dissapates fairly quickly, so there has to be a continuous source. Hope they can find out -- this is exciting.

cows on Mars.