See this crack? The one that looks sort of like a wishbone, right above that dark swath?

NASA Goddard MODIS Rapid Response Team

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It might look like a hairline fracture from that far above, but it’s actually massive:

German Aerospace Center

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It’s a crack in the Pine Island Glacier ice shelf, which NASA calls “one of the largest and fastest-moving glaciers in Antarctica.” The crack is 18 miles long. That’s longer than the length of Manhattan, by more than four miles.

That bit of glacier on the other side of the crack? If it breaks off, it would create a floating iceberg. An iceberg longer than Manhattan. That wouldn’t just sink a ship, it would obliterate it.