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Mega Canyon Discovered Under Greenland Ice
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Mega Canyon Discovered Under Greenland Ice

September 11, 2013
Hidden for all of human history, a 460 mile long canyon has been discovered below Greenland's ice sheet. Using radar data from NASA's Operation IceBridge, scientists found the canyon runs from near the center of the island northward to the fjord of the Petermann Glacier. Researchers believe the canyon plays an important role in transporting sub-glacial meltwater from the interior of Greenland to the edge of the ice sheet into the ocean. Evidence suggests that before the presence of the ice sheet, as much as 4 million years ago, water flowed in the canyon from the interior to the coast and was a major river system. Credit: NASA's Goddard Space Flight Center