Frankly, if I were Michael Mumma, I'd be going nuts right now. The NASA scientist and his colleagues have either found evidence of life on Mars, or are getting fooled by some weird geochemistry.
The researchers today today are reporting that in 2003 and 2006, they recorded plumes of methane rising from the surface of the Red Planet. Working back from their measurements of methane in the air, the researchers pinpointed some particular spots on Mars where the methane came from. And it's a lot of methane they're talking about--19,000 metric tons of the stuff in one plume. It's coming out of Mars at the same rate seen at methane-producing spots on Earth.
Those places on Earth happen to be places where microbes are churning the gas out. There might be other ways of getting plumes of methane into the air--generating it from magma, for example. But in a paper ...