Curiosity rover’s repeated detections of methane right above the surface of Gale Crater has captivated scientists and non-scientists alike because it may imply that microbes were, or are, present on the Mars . it's also, however, possible that the gas was produced thanks to the geological processes that involve the interaction of rocks, water, and heat.
But the mystery of methane gas intensified after ExoMars Trace Gas Orbiter sent by the ecu Space Agency (ESA) did not detect any methane higher within the Martian atmosphere.
Chris Webster, a senior research scientist at Nasa’s reaction propulsion Laboratory (JPL), said he was fully expecting the Trace Gas Orbiter team to report that there’s alittle amount of methane everywhere on Mars when the orbiter came onboard in 2017.
“But when the ecu team announced that it saw no methane, i used to be definitely shocked,” said Webster, lead of the Tunable Laser Spectrometer (TLS) instrument within the Sample Analysis at Mars (SAM) chemistry laboratory aboard the Curiosity rover.
The TLS has measured but one-half part per billion (in volume) of methane on the average in Gale Crater, punctuated by spikes of up to twenty parts per billion in volume. The contradictory data from the high precision of Curiosity’s TLS and therefore the European orbiter, designed to be the gold standard for measuring methane and other gases over the entire planet, baffled the scientists.
John E Moores, a planetary scientist from York University in Toronto, published an intriguing prediction in 2019 asking “what if Curiosity and therefore the Trace Gas Orbiter both are right?" The hypothesis suggested that the discrepancy between methane measurements comes right down to the time of day they’re taken.
TLS operates mostly in the dark when no other Curiosity instruments are working since it needs tons of power. Moores noted that the Martian atmosphere is calm in the dark , therefore the methane seeping from the bottom builds up near the surface where Curiosity can detect it. On the opposite hand, the ecu orbiter requires sunlight to pinpoint methane about 5 kilometres above the surface.
During the daytime, warm air rises and funky air sinks. The methane gas detected near the Martian surface in the dark gets mixed into the atmosphere during the day, getting diluted to undetectable levels.
The Curiosity team decided to check Moores’ prediction and powered TLS over the course of 1 Martian day, bracketing one night-time measurement with two daytime ones. SAM sucked in Martian air for 2 hours, leaving a concentrated sample of methane that TLS could easily measure by passing an infrared beam through it repeatedly
“John predicted that methane should effectively go right down to zero during the day, and our two daytime measurements confirmed that,” said Paul Mahaffy, the PI of SAM.
While the scientists were ready to solve the mystery behind variations, they're yet to unravel the worldwide methane puzzle at Mars. consistent with Nasa, methane may be a stable molecule that's expected to last on Mars for about 300 years before getting torn apart by radiation . But scientists suspect that something is destroying methane on Mars in but 300 years, given the constant seeping of methane from similar craters should have accumulated enough within the atmosphere for the Trace Gas Orbiter to detect.
