A huge crater has been discovered under a layer of ice in Antarctica.

A massive crater, 480 kilometers in diameter, has been discovered beneath Antarctica's eastern Arctic ice sheet, which may be the remains of a meteorite impact 250 million years ago. Scientists, using data from NASA satellites, suggest that this event may have contributed to the "great extinction," during which 95% of marine and 70% of land life on Earth disappeared. Professor Ralph Von Frese of Ohio State University emphasizes that the impact may have had a greater impact than that which led to the extinction of the dinosaurs. An international team of scientists from the US, Russia, and Korea is investigating this phenomenon.

A 480-kilometer-wide crater (satellite image below) has been discovered beneath the eastern Arctic ice sheet. Scientists say this discovery could be the mark of the first massive meteorite impact 250 million years ago. The Wilkes Land singularity was discovered using NASA satellites to map subtle differences in Earth's weight.

"The Wilkes Land impact was larger than the one that killed the dinosaurs," said Professor Ralph Von Frese of Ohio State University in the US. If the crater truly formed at that time, Von Frese and his colleagues believe it would be of interest as a possible cause of the "Great Extinction"—the largest mass extinction on Earth, when 95 percent of marine and 70 percent of land animals disappeared from the planet. Some scientists have suspected that the Permian-Triassic extinction may have occurred suddenly—due to environmental changes brought on by the impact of a giant space rock. This is a similar argument to the one that explains the end of the dinosaur era, which occurred 65 million years ago.

A geological feature known as Bedouta Hill, located on the seafloor off Australia, has been considered a possible meteorite impact crater. However, the explanation for the large-scale impact death is difficult to confirm.

Earth may have been struck by an extraterrestrial object, but it was likely just a fragment of some larger cosmic killer, other researchers believe.

The Ohio team used gravity variations estimated from Antarctic surface data from the US Space Agency's Grace satellite. Team members are from the US, Russia, and Korea.

Information about the crater was first presented at the American Geophysical Society General Assembly in Baltimore in June this year.