PIX4616544: Glaciers under Martian crateres - Buried glaciers on Mars - Computer reconstructed views of three Martian crateres in the Hellas region that house glaciers. The images show the crateres as they appear today with a layer of Martian soil covering the ice with water and, on the right, the glaciers updated according to radar measurements obtained by the Mars Reconnaissance Orbiter probe (MRO). These glaciers would have a thickness of 250 to 450 meters. Each image covers 20 km wide. This computer graphic image shows three craters in the eastern Hellas region of Mars containing concealed glaciers detected by radar. The images shows how the surface looks today with the ice covered with a layer of Martian soil and what the ice may look like underneath. The image was created using image data from the Context Camera on the Mars Reconnaissance Orbiter (MRO) spacecraft combined with results from the SHARAD radar sounder on MRO and HRSC digital elevation map from the Mars Express spacecraft. The color of the Martian surface and ice was estimated from MRO HiRise color images of other Martian craters and the polar ice caps. The buried ice in these craters as measured by SHARAD is ~ 250 meter thick on the upper crater and ~ 300 and 450 meters on the middle and lower levels respectively. Each image is 20 km (12.8 mi.) across and extends to 50 km (32 mi) in the distance. Recent measurements from the Mars Reconnaissance Orbiter SHARAD radar sounder have detected large amounts of water ice in such deposits over widespread areas, arguing for the flow of glacial - like structures on Mars in the relatively recent geologic past. This suggests that snow and ice accumulated on higher topography, flowed downhill and is now protected from sublimation by a layer of rock debris and dust. Furrows and ridges on the surface were caused by deforming ice / Bridgeman Images

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