A23a, the world's largest iceberg, has baffled scientists by getting trapped in a spinning vortex just north of Antarctica, instead of drifting away as expected. This iceberg, larger than Greater London, was supposed to be racing north in the powerful Antarctic Circumpolar Current, but instead, it's caught in a giant rotating water column called a Taylor Column, causing it to spin in place and delay its melt. This unusual phenomenon, discovered in the 1920s, is keeping A23a from breaking apart ...