Last year, a huge chunk of ice broke off of Pine Island Glacier in Antarctica—and an iceberg six times the size of Manhattan was born. Dubbed B31, the iceberg "is now well out of Pine Island Bay and will soon join the more general flow in the Southern Ocean," says an expert in a NASA report. It could pose problems for shipping routes, CNN reports, particularly as Antarctic winter darkness makes it harder for researchers to keep tabs on it.
NASA has been tracking the iceberg for five months, io9 reports. "It has been surprising how there have been periods of almost no motion, interspersed with rapid flow," the researcher says. Some 20 miles long, 12 miles wide, and perhaps a third of a mile thick, it will probably stick around for at least a year before melting or breaking up, another expert notes.