Our relationship with methane is complicated. As natural gas, it’s an efficient fuel that that produces less carbon dioxide than other hydrocarbons. As cow farts, it's a greenhouse gas often blamed for contributing to climate change. As an abundant substance trapped in permafrost, it gets explosively released when said climate change melts the permafrost in Siberia, creating massive holes. And, as a product of microbial methanogenesis, it’s an important sign that a planet may contain life, or at least have the ingredients to support it. The discovery of methane on Mars in 2004 got the scientific and let’s-move-to-Mars worlds excited. Unfortunately, the party may have been premature – new data shows that all of the Martian methane has disappeared. Who lit a match?
“The presence of methane has been confirmed thanks to the observations of the Planetary Fourier Spectrometer (PFS) on board Mars Express during the past few weeks.”
That was the news in 2004 when the European Space Agency’s ESA Mars Express orbiter detected methane in the Martian atmosphere. The next question was, “Where does this methane come from?” One possibility is from above when organic carbon from solar system dust falls to the surface and reacts with solar radiation to form methane. Another is from below, produced by chemical reactions or live or decayed microorganisms. In 2014, NASA’s Curiosity rover detected a seasonal spike in methane – unexplained but still confirming the presence of the gas.
Then came the spoiler. In 2016, the ESA launched the Trace Gas Orbiter (TGO) which began scanning the Martian atmosphere this year arrived at Mars in 2016, this year began to scan the atmosphere for methane with Belgium’s Nadir and Occultation for Mars Discovery (NOMAD) spectrometer and the Atmospheric Chemistry Suite spectrometer developed by Russia. Designed to detect very low levels of atmospheric methane (about 50 particles per trillion), scientists were confident they would finally get solid gas data.
“But we already know we can’t see any methane.”
There's no methane showing up on Mars. Ann Carine Vandaele, NOMAD’s principal investigator and a planetary scientist at the Royal Belgian Institute for Space Aeronomy in Brussels, delivered the disappointing news this week at the semiannual meeting of the American Geophysical Union in Washington, D.C. Yes, they gave the TGO a software whack upside its head to make sure it was functioning normally and it was. How bad is this news? It could mean that there isn’t and never was any life on Mars, and there’s no methane that could possibly be used as a fuel by settlers from Earth.
The researchers aren’t giving up, especially since the Trace Gas Orbiter will be operational until at least 2022. They're hoping there might be a mistake or they may find a sign this is just a temporary aberration and the methane is hiding somewhere. However, they probably already feel the same way Looney Tunes’ star Marvin the Martian often felt:
"This makes me very angry, very angry indeed."