Fresh signs of water on Mars

THE twin Mars rovers have found more evidence the Red Planet once had water, NASA scientists say.

The robotic vehicles landed in January and first found signs in March that Mars had water aeons ago.

The Spirit rover has now rolled nearly two miles across the plains of its Gusev Crater landing site and into an area dubbed the Columbia Hills.

Perched about 30 feet above a plain, it recently found indications water had altered an outcropping of bedrock, scientists at the Jet Propulsion Laboratory in Pasadena said.

Sulphur, chlorine and bromine found inside the rock were in much greater concentrations than in rocks on the plain. Those elements are commonly emitted from volcanoes and could have combined with liquid water or water vapour.

“We have a deeper alteration, suggesting much more water,” said Steve Squires, principal investigator for science instruments aboard the rovers.

Meanwhile, halfway around the planet, the Opportunity rover has rolled into Endurance Crater, a stadium-sized depression. At the bottom, it found rippled dunes and a bizarre rock with a lumpy appearance.

“It doesn’t look like anything we’ve seen anywhere else,” Mr Squires said.