A crack 20 miles long and 20 feet deep has formed in the shelf of floating ice at the foot of the Pine Island Glacier, one of the largest and fastest-moving tongues of ice on the Antarctic continent, the BBC reported Thursday.
NASA scientists said the eventual iceberg would cover about 340 square miles.
"The last big calving event occurred in 2001 so in general people have been expecting something like this to happen fairly soon, and for us it is very exciting to see this while it is happening," Micheal Studinger, a scientist with NASA's Icebridge project, said.
The Icebridge project has been conducting instrumented airborne missions flying from Chile to measure the thickness of the ice in the region.
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