The asteroid that made the crater at Wilkes Land, underneath the East Antarctic Ice Sheet, could have been what caused the Great Dying 250 million years ago, when about 90 per cent of life on Earth was wiped out NASA Goddard Space Flight Center / Flickr

A group of conspiracy theorists called Secure Team 10 has been peddling a wonderfully imaginative idea about a Nazi WWII camp for flying saucers located at a site in Wilkes Land in East Antarctica. The anomaly that the theorists picked up on in fact marks a possible cause of the greatest extinction event ever to happen on Earth.

Wilkes Land crater
Above, GRACE-measured gravity fluctuations beneath East Antarctica . Denser regions appear more red; the location of the Wilkes Land crater is circled Ohio State University

It's true that there is a gravitational anomaly at Wilkes Land that was picked up by satellite measurements. Scientists discovered the anomaly in 2006, suggesting that there was a large asteroid impact site in the land that lies about 1.6 kilometres beneath the East Antarctic Ice Sheet.

Wilkes Land crater
Above, thickness of the Earth's crust across Antarctica . Thicker crust appears red. The location of the Wilkes Land crater is circled Ohio State University

The anomaly that the scientists detected was a mascon – a geological phenomenon found when an asteroid slams into the surface and causes the Earth's mantle to push up into the crust beneath the crater.

Such features are common the moon, which is not geologically active, but on Earth they tend to get "scrubbed" out at the surface, study author Ralph von Frese of Ohio State University in the US said at the time.

The crater was measured to be 480km across, making it more than twice the size of the Chicxulub crater in Mexico that is believed to mark the impact of the asteroid that killed the dinosaurs at the end of the Cretaceous period, 65 million years ago.

The Wilkes Land crater is thought to be the site of impact of the asteroid that caused the Great Dying, about 250 million years ago, according to the research that was first reported in 2006.

"This Wilkes Land impact is much bigger than the impact that killed the dinosaurs, and probably would have caused catastrophic damage at the time," study author Ralph von Frese said.

"All the environmental changes that would have resulted from the impact would have created a highly caustic environment that was really hard to endure. So it makes sense that a lot of life went extinct at that time."

Really, no Nazi flying saucers required