New Evidence Of Water Adds To 'Life On Mars' Discussion

NASA said it had discovered new evidence that water flows periodically on the surface of Mars, raising the possibility of life existing on the Red Planet. Pictures taken by the orbiting Mars Global Surveyor in 2004 and 2005 indicated two separate deposits of water - now dried up - in gullies on the slopes of craters on the surface. Both deposits are several hundred metres long and suggest water flowed some time in the last seven years. 'These observations give the strongest evidence to date that water still flows occasionally on the surface of Mars,' said Michael Meyer, lead scientist for NASA's Mars Exploration Programme.Evidence has been hard to come by because any water that may break the surface can only remain liquid for extremely short periods of time, given the planet's extremely cold temperature and thin atmosphere. Liquid water, rather than ice or water vapour which has already been shown to exist on Mars, is considered necessary for any life forms to survive on the planet. 'These fresh deposits suggest that at some places and times on present-day Mars, liquid water is emerging from beneath the ground and briefly flowing down the slopes,' said Michael Malin of Malin Space Science Systems and lead investigator of the photographs.'This possibility raises questions about how the water would stay melted below ground, how widespread it might be, and whether there's a below-ground wet habitat conducive to life,' Malin said.