The discovery of life on Mars would get pretty much everyone excited. But the scientists hunting for it would probably be happy no matter what the outcome of their search-whether life turned out to extinct, dormant or extant. They’d even consider finding no evidence of life whatsoever to be an important discovery.
There have been no direct observations of living organisms or fossils on Mars so far. But there are other types of evidence. One of the most often cited is the controversial detection of methane in the planet’s atmosphere, first in 2004 and then in 2014. Now a new paper, published in Nature Geoscience, reports a fresh detection of methane in the planet’s atmosphere, along with a theory of where it came from.
The significance of the data arises from the feature that the team selected to track: the Gale Crater. Finding where the methane came from is only a stage in determining how it formed. Importantly, there are many mechanisms other than living organisms that could have produced it, for example geological processes. For example, a geological event may have fractured the ice containing bubbles of methane to release it into the atmosphere.
So whatever the source, it does seem there may be methane on Mars after all. However, we’ll need further confirmation to be completely sure. Fortunately, fresh findings are most likely to be available soon. The team that failed to discover methane with the Trace Gas Orbiter has been analysing new data for several months.