'Missing Something Important' on Mars?

"We must be missing something quite important," on Mars French scientist Dr. Franck Lefevre says about the study of methane who, along with associate Dr. Francois Forget, created a computer model that shows methane gas unevenly distributed in the Martian atmosphere that changes with the Red Planet's seasons.

Methane gas was first discovered in the Martian atmosphere in 2004 by the European Space Agency's Mars Express. The measurements indicate that either there is life on Mars, or that volcanic activity continues to generate heat below the martian surface. Either outcome is big news for a planet once thought to be biologically and geologically inactive.

The reason is that on Earth much of the methane in our atmosphere is released by evolved life forms, such as cattle digesting food. While there are ways to produce methane without life, such as by volcanic activity, it is the possible biological route that has focused attention on the discovery noted Agustin Chicarro, ESA Mars Lead Scientist.

The current chemistry as we know it is not consistent with the measurements of methane on Mars. There is something else going on, something that lowers the methane lifetime by a factor of 600. So if the measurements are correct, we must be missing something quite important," Dr. Lefevre says about his compuer model study at the Universite Pierre et Marie Curie in Paris, France.

Clearly something unusual is going on at Mars. Methane was thought to be stable in the Mars atmosphere for around 300 years but instead of taking 300 years to disappear, the methane had almost entirely vanished by early 2006, according to a study led by Michael Mumma of NASA’s Goddard Space Flight Center in Balitmore, Maryland.

Yet the two French scientists conclude in their published article in Nature 460, 720 (2009)that: “Such a [methane] lifetime suggests that organics are quite readily scavenged from the modern Martian environment, if reactions in the surface are the only cause of the observed methane variations. This would leave little hope that life as we know it can exist at present or that evidence of past life can be preserved in the shallow surface layer.”

More from the ESA, BBC, Space.com, and Geology. The next mission to Mars is set to begin in October with Chinese and Russian spacecraft probes.