IFLScience smells more traces of life on Mars, by curiously sniffing spikes of Red Planet methane:
Since it landed on the Red Planet, NASA’s Curiosity rover has been exploring the Gale crater in search of clues that will explain how the Martian landscape has changed over time. The rover has now identified a spike of methane in the atmosphere of Mars, corroborating previous elusive observations of methane that could not be readily explained for decades.
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The study utilized readings obtained over the course of almost two years using the Sample Analysis at Mars instrument suite’s tunable laser spectrometer. The average methane concentration is fairly stable at 0.7 parts per billion by volume (ppbv), though there were spikes that brought the amount up to 7 ppbv. This fluctuation is about ten times greater than normal….
Methane is a common byproduct of biological processes, but that is not the only way it is created. The presence of methane alone is not enough to say that life exists, or once existed, on Mars. However, it is still not clear where the methane is coming from. Future research will need to determine the origin of the methane as well as further investigate why it has spikes in certain areas.