NASA’s Opportunity rover has seen a mineral on Mars that could only have formed in the presence of liquid water.
“This is the single most powerful piece of evidence that water once flowed on Mars that has been discovered,” said planetary scientist Steve Squyres of Cornell University during a briefing at the 2011American Geophysical Union meeting on Dec. 7. “There’s no ambiguity about this.”
Researchers have found a bright vein of gypsum, a mineral that could only have been deposited by water. The finding suggests that billions of years ago warm water flowed through underground fractures in the rocks. via Wired
December 8, 2011
