7 billion years ago,

NASA's Curiosity ie "worry"'s robotic spacecraft on Mars in the past, was able to find evidence of the presence of water.

'Curiosity', a classic çakılkayanın, ie, a different picture of a rock formed by the merger of pebbles and grains of sand on Earth sent earlier in the day. Scientists in the gravel size and round shapes of these stones show moved to water erosion and thinking. The robot finds an old river bed is predicted.

7 billion years ago,

NASA's Mars rocks lab introduced to the press in California, where the ground is currently thought to reach seven billion years ago. University of California, Berkeley, and the "worry" team, Bill Dietrich, "in flow estimate that it takes hundreds of thousands of years," he said. ?