Methane Spikes on Mars
3-Year Seasonal Fluctuations in Methane, Gale Crater, Mars (credit: Curiosity mission/JPL)
When trying to identify a culprit in a crime investigation the old adage of follow the money is always applied. If you're looking for life on another planet, the adage might need to be follow the methane. On Earth this gas most often results from ongoing biological activity like decaying vegetation. In what is a major step to potential detect existing life on Mars, the Jet Propulsion Laboratory at CalTech is now reported two discoveries made by the Curiosity rover including surface methane measurements. According to the announcement, JPL investigators report:
"new findings of 'tough' organic molecules in 3-billion-year-old sedimentary rocks near the surface of Gale Crater, as well as seasonal variations in the levels of methane in the atmosphere".
Curiosity carries an instrument called the Sample Analysis at Mars (SAM) to detect atmospheric constituents. The instrument gathered signals for methane over three Martian years (nearly six Earth years), that peaked during the Martian summer. NASA's associate administrator of science said of the analysis published in Science:
"With these new findings, Mars is telling us to stay the course and keep searching for evidence of life. I'm confident that our ongoing and planned missions will unlock even more breathtaking discoveries on the Red Planet."
Methane dissipates within a brief time so something must be replenishing the gas on a consistent basis. While the new measurements indicate fluctuations in the presence of methane, the Curiosity rover doesn't carry instruments that can determine the source of the gas or its atomic structure. The European Space Agency's Insight lander presently on Mars should be able to determine the molecular composition and if it is of geological or biological origin.
Finger's crossed that the adage of follow the methane detects biological a 'pot of gold' at the end of a Martian rainbow.
WHB