New data pinpoint Mars' wet and balmy past

PARIS (AFP) — Water bathed the surface of southern Mars for millions of years, helping to create an environment theoretically capable of nurturing life, according to a new study into the planet's mysterious oceans.

Scientists at Brown University in Rhode Island used an instrument aboard a US spacecraft, the Mars Reconnaissance Orbiter, to hunt for traces of phyllosilicates, or clay-like minerals that preserve a record of water's interaction with rocks.

They found phyllosilicates in thousands of places, in valleys, dunes and craters in the ancient southern highlands, pointing to an active role by water in Mars's earliest geological era, the Noachian period, 4.6 to 3.8 billion years ago.

"These results point to a rich diversity of Noachian environments conducive to habitability," the authors conclude.

An intriguing find was of deposits in the pointed peaks at the centre of craters. These peaks are generally taken ...