New York: A Nasa rover on Mars has found methane, a possible piece of evidence of life on the Red Planet.

The Curiosity robot measured a spike in methane in the atmosphere twice, in late 2013 and early 2014, with readings 10 times higher than measurements before and after, the National Aeronautics and Space Administration (Nasa) said on Wednesday in a statement.

“This temporary increase in methane—sharply up and then back down—tells us there must be some relatively localized source," said Sushil Atreya, a member of Curiosity’s science team. “There are many possible sources, biological or non- biological."

Methane, a chemical compound made of carbon and hydrogen, could have been produced by microorganisms called methanogens, which produce methane as a byproduct. Non-biological explanations include a geological process called serpentinization, which forms methane, or the effect of meteorites, though the scientists said “no new impact craters have been observed." The findings were published today on the website of the journal Science.

Curiosity’s readings “do not reveal whether Mars has ever harbored living microbes, but the findings do shed light on a chemically active modern Mars and on favorable conditions for life on ancient Mars," Nasa said.

The robot also picked up other organic chemicals in powder drilled from a rock, which the agency said is the first definitive detection of organics in the surface materials of Mars. The organic material may be native to Mars or could have been transported to the planet by meteorites.

Curiosity, launched from Cape Canaveral, Florida, in November 2011, has been roving the Red Planet since touching down in August 2012. Determining whether Mars ever could have supported life is one of its main goals. It’s part of Nasa’s research in preparation for a human mission to Mars in the 2030s. Bloomberg