91Èȱ¬

The discovery of methane on the Red Planet is important because here on Earth, 95% of the gas comes from microbial organisms, giving researchers hope that there might really be life on Mars.

Curiosity scientist professor Sushil Atreya told the Today programme: "We’ve been observing methane on Mars for two years… and we have been detecting very low levels…suddenly last November we began to see larger amounts of methane, about 10 times more."

"At the moment we cannot say that there is any form of life on Mars… there’s a 50/50 chance."

First broadcast Today programme 17 December 2014.