There’s a methane mystery brewing on Mars.
Scientists first detected traces of methane gas on Mars years ago, and it was exciting because the compound is a sign of life here on Earth. But a European orbiter has yet to find any evidence of methane in the planet’s atmosphere, despite being expressly made for the purpose. It’s complicating scientists’ search for life on the Red Planet.
Traces of methane were first detected in Mars’ atmosphere by the European Space Agency’s (ESA) Mars Express orbiter in 2004. But, while some reveled in the discovery, other researchers believed the instrument wasn’t sensitive enough to create reliable results because it could only measure methane at a level of 10 parts per billion (ppb).
Ten years later, NASA’s Curiosity rover detected methane again in the planet’s Gale Crater. This past summer, Curiosity made another major methane discovery when it found that the Red Planet ...
