Curiosity rover finds evidence of ancient streambed on Mars

September 30, 2012 – SPACE – The Curiosity rover has come across a place in Gale Crater where ankle-to-hip-deep water once vigorously flowed: an ancient streambed containing evidence of gravel that has been worn by water. At a press briefing today, members of the Mars Science Laboratory team said the rover has found “surprising” outcrops and gravel near the rover landing site that indicate water once flowed in this region, and likely flowed for a long time. “Too many things that point away from a single burst event,” said Curiosity science co-investigator William Dietrich of the University of California, Berkeley. “I’m comfortable to argue that it is beyond the 1,000 year timescales, even though this is very early on in our findings.” From the size of gravel found by the rover, the science team can interpret the water was moving about 1 meter (3 feet) per second, with a depth somewhere between ankle and hip deep. “Plenty of papers have been written about channels on Mars with many different hypotheses about the flows in them,” said Dietrich. “This is the first time we’re actually seeing water-transported gravel on Mars. This is a transition from speculation about the size of streambed material to direct observation of it.” What Curiosity found on Mars was described as conglomerate rock made up of water-transported gravels, meaning the gravel is now cemented into a layers of rock, and the sizes and shapes of stones offer clues to the speed and distance of a long-ago stream’s flow. “The shapes tell you they were transported and the sizes tell you they couldn’t be transported by wind. They were transported by water flow,” said Curiosity science co-investigator Rebecca Williams of the Planetary Science Institute. –Universe Today