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B.B.C. Article
Methane 'belches' detected on Mars
Nasa's Curiosity rover has detected methane on Mars - a gas that could hint at past or present life on the planet.
The robot sees very low-level amounts constantly in the background, but it also has monitored a number of short-lived spikes that are 10 times higher.
Methane on the Red Planet is intriguing because here on Earth, 95% of the gas comes from microbial organisms.
Researchers have hung on to the hope that the molecule's signature at Mars might also indicate a life presence.
The Curiosity team cannot identify the source of its methane, but the leading candidate is underground stores that are periodically disturbed.
Curiosity scientist Sushil Atreya said it was possible that so-called clathrates were involved.
"These are molecular cages of water-ice in which methane gas is trapped. From time to time, these could be destabilised, perhaps by some mechanical or thermal stress, and the methane gas would be released to find its way up through cracks or fissures in the rock to enter the atmosphere," the University of Michigan professor told BBC News.

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NASA Article
NASA Goddard Instrument Makes First Detection of Organic Matter on Mars
The team responsible for the Sample Analysis at Mars (SAM) instrument suite on NASA's Curiosity rover has made the first definitive detection of organic molecules at Mars. Organic molecules are the building blocks of all known forms of terrestrial life, and consist of a wide variety of molecules made primarily of carbon, hydrogen, and oxygen atoms. However, organic molecules can also be made by chemical reactions that don't involve life, and there is not enough evidence to tell if the matter found by the team came from ancient Martian life or from a non-biological process. Examples of non-biological sources include chemical reactions in water at ancient Martian hot springs or delivery of organic material to Mars by interplanetary dust or fragments of asteroids and comets.

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