World's largest iceberg is on the move for first time in 37 years

The world's largest iceberg has moved for the first time in 37 years, after being grounded on the sea floor in Antartica since breaking off a glacier decades ago.

The A23a is on a journey out of the Weddell Sea following its 1986 grounding, according to the British Antarctic Survey.

A23a is more than twice the size of New York City, measuring around 1,500 square miles. It first calved, or broke off, from the Filchner Ice Shelf.

The iceberg was dethroned as the largest in the world in 2021, losing the title briefly to the A76 iceberg after it broke off from the Ronne Ice Shelf in the Weddell Sea.

But A76 has since broken up into separate pieces, handing the title back to A23a, among the world's oldest icebergs as well.

The largest iceberg ever recorded was the B-15, which broke off from its ice shelf in 2000 and measured more than 4,000 square miles before it began to melt.