Mashable reports on the Mars Rover Curiosity, which has just found evidence of some major flooding and splishing and splashing on the surface of Mars long ago:
Although Mars today is 1,000 times drier than the driest desert on Earth, the rover has spotted clues that long ago the Red Planet experienced momentous floods. It was a wet world.
“This was not a quiet period on Mars,” Becky Williams, a scientist at the Planetary Science Institute who researches Mars using the rover’s Mast Camera, said in a statement. “There was an exciting amount of activity here. We’re looking at multiple flows down the channel, including energetic floods and boulder-rich flows.”
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Curiosity also closely examined these water-tumbled rocks. A number of them contain telltale “halo” markings, as seen in the image below. “Finally, water soaked into all the material that settled here,” the space agency explained. “Chemical reactions caused by the water bleached white ‘halo’ shapes into some of the rocks.”
Lots of photos at the link.