Mars Streambed | NASA Planetary Sciences

NASA Jet Propulsion Laboratory scientist Sanjeev Gupta uses images captured by Curiosity rover to explain the significance of pebbles found on Mars. Gupta describes the ground-layer composition at three outcrops near the rover's landing site that contain rounded pebbles. Because rounded pebbles on Earth are a sign that rocks have been transported by water, and because the Mars pebbles are found among cone-shaped deposits that resemble alluvial fans at the mouths of rivers on Earth, Gupta and other scientists think they have discovered the first convincing evidence of gravel transported by water on the surface of Mars. CREDITS: License:

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