Concrete Evidence for Water On Ancient Mars

摘要

Billions of years ago, enough water flowed into Gale crater fast enough to carry gravel to the middle of the crater floor-where the Curiosity rover has found and imaged it, the NASA mission's team reported in a press conference on 27 September. The broken face of a 15-centimeter-thick layer of rock sports bits of stone worn into pebbly roundness as they tumbled down from the nearby crater rim in a torrent of water. Previous Spirit and Opportunity rover investigations and orbital imaging have found evidence of salty ground water, evanescent puddles of brine, and flowing rivers on ancient Mars.