Using satellite technology to observe the Antarctic gravity field from thousands of miles above the earth, the international team of geophysicists found evidence of many large meteorite impact sites across the entire continent.
Presenting their research to the International Geographical Congress in Glasgow this week, the results of the imaging revealed that the sites extend from the Ross Sea in the vicinity of the Pacific Ocean, to the Weddell Sea south of the Atlantic Ocean.
However, those wishing to make a journey to Antarctica to see for themselves the craters left by the interstellar objects will be disappointed. Lying beneath the East Antarctic continental ice sheet, most of the sites are not visible because they are shielded by hundreds of millions of tons of ice.
However, offshore in the Ross and Weddell Seas impact craters can be viewed on the seabed. The area where the meteorites struck – known as scatter ellipses – is the largest so far found on Earth. It measures some 1,300 by 2,400 miles, according to the researchers.
A meteorite crater in Victoria Land, Antarctica, was discovered in the 1970s by the United States Antarctic Research Programme. The site was found after changes to the gravity below the ice were observed – a sign of the mass of rock blasted from the crater when the meteorite crashed and exploded, killing every living thing for hundreds of miles around.
The new discovery of a scatter ellipse shows a much greater apparent impact event than previously known.
It is not yet clear when the meteorites hit Earth or their origins. They may have come from an asteroid belt which is located roughly 484 million miles from Earth.
Alternatively, they may have been swarms of comets or comet fragments from the solar system’s very distant Oort Cloud, 7,000 trillion miles from Earth, said Dr Frans van der Hoeven, of Delft University of Technology, in the Netherlands, who led the research.
The scientists estimate that the meteorite impacts could have disrupted the continental ice sheet, capable of creating ice flows into the adjoining ocean. This could have raised sea levels worldwide, with increases ranging anywhere from a few feet to more than 100ft.
The world’s most famous meteorite impact crater, the Barringer Meteorite Crater, is a gigantic hole in the middle of the arid sandstone of the Arizona desert in the US.
A rim of smashed and jumbled boulders, some of them the size of small houses, rises 150ft above the level of the surrounding plain. The crater itself is nearly a mile wide and 570ft deep.
When Europeans first discovered the crater, the plain around it was covered with chunks of meteoritic iron – more than 30 tons of it.