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IN SPACE - JULY 16: In this handout image supplied by the European Space Agency (ESA) on July 16, 2008, The Echus Chasma, one of the largest water source regions on Mars, is pictured from ESA's Mars Express. The data was acquired on September 25, 2005. An impressive cliff, up to 4000 m high, is located in the eastern part of Echus Chasma. Gigantic water falls may once have plunged over these cliffs on to the valley floor. The remarkably smooth valley floor was later flooded by basaltic lava. (Photo by ESA via Getty Images)