Mars rocks 'may contain evidence of life'

Rocks have been identified on Mars which may contain evidence of life, researchers have said.

Published: 7:10AM BST 30 Jul 2010

Scientists hope to find fossilised remains in the Nili Fossae rocks after discovering they are almost identical to rocks in the Pilbara region of north-west Australia where some of the earliest evidence of life on Earth was recorded and preserved.

A report in the journal Earth and Planetary Science Letters published today suggests that evidence of life on Mars could have been preserved in the same mineral form.

Scientists from the Search for Extraterrestrial Intelligence Institute (Seti) in California, used infrared light to study the Nili Fossae and Pilbara rocks.

They found that the ancient rocks shared similar minerals and features, known as “stromatolites”. It is significant because Pilbara is used to study the early stages of life on Earth 3.5 billion years ago.

Adrian Brown from the Seti Institute, who led the research, told BBC News: “Life made these features. We can tell that by the fact that only life could make those shapes; no geological process could.

“If there was enough life to make layers, to make corals or some sort of microbial homes, and if it was buried on Mars, the same physics that took place on Earth could have happened there.”

The Nili rocks, which have existed for three-quarters of the history of Mars, are four billion years old and contain carbonates – first discovered in 2008.

Carbonate, which exists in the fossilised remains of shells and bones, is formed when water and carbon dioxide mix with calcium, iron or magnesium. Its discovery countered the theory that all water on Mars was at one time acidic and was the clearest evidence yet that the Red Planet was habitable.

http://www.telegraph.co.uk/science/space/7918003/Mars-rocks-may-contain-evidence-of-life.html