The huge and mysterious "anomaly" is thought to be lurking beneath
the frozen wastes of an area called Wilkes Land. It stretches for a distance of 151 miles across and has a maximum depth of about 848 metres. Some researchers believe it is the remains of a truly massive asteroid which was
more than twice the size of the Chicxulub space rock which wiped out the dinosaurs.
If this explanation is true, it could mean this killer asteroid caused the Permian - Triassic extinction event which killed 96 percent of Earth's sea creatures and up to 70 percent of the vertebrate organisms living on land.
A view of Antarctica, the frozen landmass at the south pole of our planet
However, the wilder minds of the internet have come up with their own theories, with some conspiracy theorists claiming it could be a massive UFO base or a portal to a mysterious underworld called the Hollow Earth.
This "Wilkes Land gravity anomaly" was first
uncovered in 2006, when NASA satellites spotted gravitational changes which indicated the presence of a huge object sitting in the middle of a 300 mile wide impact crater.
The area known as Wilkes Land is circled in red
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