Nasa: Rock Shows Mars Life Could Have Existed

Nasa scientists have said analysis of a rock sample collected on Mars shows the planet could have supported primitive life.

Sulphur, nitrogen, hydrogen, oxygen, phosphorus and carbon - some of the key chemical ingredients for life - were discovered in a tiny sample collected by the rover Curiosity after it drilled into a rock.

At a briefing at Nasa's Washington headquarters on Tuesday, experts said the rock contained clay minerals that formed in a watery environment that may have been favourable for microscopic organisms.

Michael Meyer, lead scientist for Nasa's Mars Exploration Programme, said: "A fundamental question for this mission is whether Mars could have supported a habitable environment.

"From what we know now, the answer is yes."

Curiosity had already found a hint of the site's watery past - an ancient streambed that the six-wheel rover crossed.

Paul Mahaffy, principal investigator at Nasa's Goddard Space Flight Centre in Greenbelt, Maryland, said: "The range of chemical ingredients we have identified in the sample is impressive, and it suggests pairings such as sulphates and sulphides that indicate a possible chemical energy source for micro-organisms."

Scientists plan to work with Curiosity in the Yellowknife Bay area of Mars for several more weeks before beginning a long drive to Gale Crater's central mound, Mount Sharp.

The rover, which is carrying 10 science instruments, landed in August last year to begin a two-year mission.