Tuesday, January 20, 2009

Mars red but not dead?

Here's physicist David Tyler's view of the current announcement about methane on Mars:
The quest for life on Mars is unabated. There is a hunger for news: even finding water is heralded as a major find - it is a though water is half-way to finding living things! Today, The Sun newspaper published a story with the headline: "Nasa reveals life on Mars" and the tagline: "ALIEN bugs are responsible for strong plumes of methane gas detected on Mars, it was claimed tonight." This story would be big news, if it were true. However, the journalism exhibited here does not convey the research findings at all well.

For several years, it has been known that methane is a component of the Martian atmosphere, and it is also known that this situation is not stable. There are various mechanisms for removing the methane and so there must be a mechanism for renewing the gas. The research paper reports on observed releases of methane, confirming that these occur and also carrying the implication that oxidising agents in the crustal materials is a bif factor in methane degradation.

The research does not reveal the source of this methane. This is left open in the research paper: it could be linked to microbial life, but it could be geochemical. "Thus, the presence of significant methane would require recent release from sub-surface reservoirs; the ultimate origin of this methane is uncertain, but it could be abiotic or biotic." and: "Both geochemical and biological origins have been explored, but no consensus has emerged".
Go here for more.