The largest iceberg in the world completes a perfect pirouette! Watch as a trillion-ton ‘megaberg’ the size of Greater London spins at the site just north of the Antarctic Peninsula

It is a floating mass of pure white ice, about the size of Greater London.

And now the world’s largest iceberg, called A23a, has completed a pirouette on its journey to the Southern Ocean.

NASA satellite images show the tooth-shaped mountain rotating more than 360 degrees between December and February, just north of the Antarctic Peninsula.

A23a is gradually eroded by waves and melts due to warmer water as it moves north, after being grounded on the ocean floor for 30 years.

According to the British Antarctic Survey (BAS), which visited A23a in December, the iceberg is moving north at a speed of about 30 miles (48 kilometers) per day.

Scientists revealed in November that the mountain is moving again. This map shows the mountain’s position marked in blue as of August (bottom) and in recent weeks (top)

Carried by wind and ocean currents, it is swept along an ‘iceberg alley’ – a common route for icebergs to drift to the sub-Antarctic island of South Georgia.

“The #A23a megamountain is in its spinning age,” said the British Antarctic Survey, which posted the animation on X (formerly Twitter).

‘These dance moves along #IcebergAlley are part of the long, melting journey from the iceberg to warmer waters.

‘Don’t let your screen size fool you, this is the largest iceberg in the world, about the size of Cornwall or Rhode Island!’

EYOS Expeditions, which arrived at A23a in January, used a drone to take the final snapshots from the sky.

EYOS videographer Richard Sidey said the A23a is ‘mind-bogglingly huge’ and ‘extends as far as you can see in either direction’.

“I don’t actually think we can fathom how big it is; we can only know how big it is through science,” he said.

A23a is the largest surviving fragment of an iceberg that broke away from the Filchner Ice Shelf in Antarctica in August 1986.

EYOS videographer Richard Sidey said A23a is ‘mind-bogglingly huge’ and ‘extends as far as you can see in either direction’

This shot highlights the loss of some of the iceberg’s mass. It is four times the size of Greater London, but getting smaller

EYOS Expeditions, which arrived at A23a in January, used a drone to take the last snapshots from the sky

It had only moved a few hundred kilometers when it became stuck on the ocean floor, eventually remaining stationary for the next thirty years.

Icebergs ‘ground’ on the ocean floor when their keel (the part below the water’s surface) is deeper than the depth of the water.

Scientists revealed in November that the mountain is moving again, being carried northward by wind and ocean currents.

They estimate that it has an area of ​​1,500 square kilometers, a volume of 263 cubic kilometers and a mass of just under a trillion tons.

That makes it not only four times as big as Greater London, but no less than 100 million times as heavy as the Eiffel Tower in Paris.

However, parts of the mountain break off as it gets further north, due to erosion and melting from the warmer water.

Like coastal erosion of land, the waves crash against the mountain, causing the holes to grow larger and larger until the top collapses.

This leaves small ‘piles’ which then form smaller ‘stumps’ before melting away completely.

While A23a originally calved off the Filchner Ice Shelf in 1986, it remained grounded on the seabed until last month

To give a sense of scale, this image shows the area of ​​the iceberg overlaid on a map of Greater London

This is a melting process that will eventually cause A23a to be lost forever, but due to its enormous size it may take some time.

If it has not melted enough by the time it reaches South Georgia – the island in the South Atlantic Ocean – it could cause problems.

There is a chance that the huge mountain could disrupt the feeding routines of wildlife such as penguins, for example if it is parked in an area where foraging is common.

“It depends on its trajectory, but there is potentially an impact on wildlife if it approaches any of the sub-Antarctic islands,” a BAS spokesperson told MailOnline.

A23a is currently the largest iceberg in the world, but this title won’t last forever because all icebergs eventually fragment.

The former record holder was A76, which broke away from an ice shelf in the Weddell Sea in May 2021, but has since fragmented into three pieces.