Mars Methane Mystery Deepens

Explanation: The methane mystery on Mars just got stranger. New results from ESA and Roscosmos ' ExoMars Trace Gas Orbiter , has unexpectedly not detected methane in the atmosphere of Mars . This result follows the 2013 detection of methane by NASA 's Curiosity rover , a result seemingly confirmed by ESA's orbiting Mars Express the next day. The issue is so interesting because life is a major producer of methane on Earth, leading to intriguing speculation that some sort of life -- possibly microbial life -- is creating methane beneath the surface of Mars . Non-biological sources of methane are also possible. Pictured is a visualization of the first claimed methane plume over Mars as detected from Earth in 2003. The new non-detection of methane by the ExoMars Orbiter could mean that Mars has some unexpected way of destroying methane, or that only some parts of Mars release methane -- and possibly only at certain times. As the mystery has now deepened, humanity's scrutiny of our neighboring planet 's atmosphere will deepen as well.