Remember the 18-mile-long canyon that was discovered by NASA at the Pine Island Glacier in Antarctica? Their researchers just completed the three-dimensional mapping of its entire surface with stunning detail, using Digital Mapping System photographs over Airborne Topographic Mapper data.
The crack formed in the ice shelf that extends from one of West Antarctica's fastest-moving glaciers. The path of the crack in this animation stretches roughly 18 miles (30 kilometers) in length (the actual crack is much longer), with an average width of about 80 metres; it was 250 metres at its widest. The canyon ranged from 50 to 60 metres, with the floor being roughly at the water line of the Amundsen Sea. Radar measurements suggested the ice shelf is about 500 metres thick, with only 50 to 60 metres of that floating above water and the rest submerged.
Once it breaks, a new gargantuan iceberg will be released to the ocean. It will be larger than New York City. [NASA Goddard Flickr]