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NASA satellite images show a huge iceberg separating from the front of Antarctica's Pine Island Glacier. According to NASA, the iceberg is 21 miles (33 km) by 12 miles (19 km) -- eight times the size of Manhattan.
Scientists have been studying Pine Island Glacier over the past two decades because it has been thinning quickly and may be one of the biggest reasons for sea level rise. The significance of this iceberg event is still to be determined, but icebergs are tracked for both scientific purposes and the danger they can pose to ships.
The crack in the ice shelf was discovered by scientists in October 2011, and over the next two years the crack widened as the 200 feet (61 m) thick glacier traveled faster than two miles (3.2 km) per year.
NASA imagery shows the iceberg breaking away from the Glacier and traveling into a basin of the Amundsen Sea in western Antarctica. The sea is mostly ice-covered, and according to NASA, the i
