World's biggest iceberg A23a captured from space, twice the size of London, now breaking apart due to...

One of the world’s largest icebergs, known as A23a, was recently photographed by the Ocean and Land Colour Instrument on the European Space Agency’s Copernicus Sentinel-3 satellite. The image was taken on April 5, 2025, and shows the massive iceberg near the remote island of South Georgia in the South Atlantic Ocean.

A23a is currently grounded on the seabed, about 73 kilometers away from South Georgia. Although the island appears only slightly in the image due to cloud cover, it is almost the same size as the iceberg. The iceberg covers an estimated 3,460 square kilometers, which is about twice the size of Greater London. In comparison, South Georgia itself spans 3,528 square kilometers, making the two landmasses nearly equal in size.

This massive block of ice originally broke off, or "calved," from the Filchner Ice Shelf in Antarctica back in 1986. For decades, it remained mostly stationary, stuck to the ocean floor. But in late 2023, it was finally dislodged and began drifting northwards due to ocean currents. Since then, it has traveled more than 2,000 kilometers, making headlines as it moved closer to inhabited or ecologically sensitive areas.

In the latest satellite image, scientists also noticed that the iceberg has started breaking apart. Many smaller chunks of ice are visible floating in the surrounding dark blue ocean, especially to the north. Experts say this kind of disintegration is common for icebergs that reach warmer waters. Rising sea temperatures and changing weather conditions speed up the melting process and cause large bergs like A23a to fall apart.

South Georgia, the iceberg's current neighbor, is a remote and mountainous island, stretching 170 kilometers in length. Its central mountain ridge reaches heights of up to 2,935 meters. Located about 1,400 kilometers east of the Falkland Islands and northeast of the Antarctic Peninsula, South Georgia is part of a British overseas territory. It is also an important site for biodiversity, home to penguins, seals, and a British Antarctic Survey research station.

The movement and breakup of A23a are being closely monitored by scientists as it helps them understand how massive icebergs behave and the effects of climate change on polar regions.