In 2003 and 2004, recordings of the spacecraft orbiting Mars and the astronomers on Earth reported detecting clouds of methane in the atmosphere. These seem to disappear a few months later.
One of the objectives of Curiosity is to determine methane in the astronomer of Mars.
Between October 2012 and June 2013, the rover took six samples of the atmosphere, none of which showed evidence of the gas.
In December 2014, NASA announced a methane spike had recorded in four samples taken in late 2013 by the rover.
This finding has excited astronomers as on Earth, methane is created as a by-product of biological process. This suggested that microbes will soon be found on the landscape.
Kevin Zahnle from the Ames Research Center said, “I am convinced that they really are seeing methane. But I’m thinking that it has to be coming from the rover.” Curiosity rover contains methane within an internal chamber, at concentrations 1,000 times higher than that needed to account for the readings.
Zahnle said he was also critical of the findings recorded by astronomers more than a decade ago.
Mission engineers told reports that although concentrations in the chamber are high; there is not enough methane in the system to trigger the observed readings.
Chris Webster of NASA’s Jet Propulsion Laboratory said, “We are continuously monitoring that methane amount and there hasn’t been evidence of any leakage during the entire mission…. To produce the amount we detected in Mars’s atmosphere, you’d need a gas bottle of pure methane leaking from the rover. And we simply don’t have it.”
Mars Curiosity team is planning to take an additional series of readings at the end of 2015.
This will be one Martian year after methane was supposedly detected by the spacecraft.
Such a finding would also make it unlikely that curiosity is the source of the gas.
The ExoMars Trace Gas Orbiter (TGO), is scheduled to launch in 2016. Once it arrives at Mars, the spacecraft will be capable of examining the atmosphere for signs of the elusive gas.
Finding methane on Mars could be the first positive sign of alien life.