The scientists believe this crater was formed by a 0.6-mile wide iron asteroid that slammed into the Earth at the end of the Pleistocene epoch, perhaps as recently as 12,000 years ago. After spotting the indentation in the radar images, the researchers set about getting samples to confirm their hunch.
This visualization begins by flying over the Greenland Ice Sheet heading northwest towards the coast of Greenland and Nares Strait.
It is in the top 25 largest craters discovered on earth and one of the youngest, with researchers saying it was created within the past 3 million years. Current estimates, based on the geological profile, seem to suggest that crater is quite young, but further analysis is required.
Evidence of the impact crater was found thanks in part to ice-penetrating radar data from Operation IceBridge, which is NASA's multi-year mission to track Earth's important ice.More news: Trump Attacks Mueller One Week After Replacing Attorney General
"Our colleagues at the Alfred Wegener Institute and University of Kansas did exactly that with a next-generation radar system that exceeded all expectations and imaged the depression in stunning detail".
"The crater is exceptionally well-preserved and that is surprising because glacier ice is an incredibly efficient erosive agent that would have quickly removed traces of the impact", he explained.
In May, 2016, a German research plane mapped a depression about 300 metres in depth under that semi-circle.
The Hiawatha impact crater was first suspected to exist in 2015, from examination of a compilation of Greenland's sub-ice topography radar measurements made by NASA over two decades.
Earlier studies have shown large impacts can profoundly affect Earth's climate, with major consequences for life on Earth at the time.More news: Facebook patches bug that could have allowed outsiders to steal user data
"Initially we thought we might find the signature from a chrondritic or "stoney" meteorite but the only explanation for the pattern of metals that we found had to be a mixture between the crustal rocks in the surrounding area and an unusual iron asteroid", Dr Iain McDonald said.
NASA said in a press release on Wednesday that its own research team will now attempt to determine when the impact occurred and how the collision affected Earth.
Searching for the impact point took researchers flew out to the glacier and collected sediments that had washed from the crater on to a nearby floodplain.
"This will be a challenge, because it will probably require recovering material that melted during the impact from the bottom of the structure", said Kjær.More news: 'Jack Reacher' TV series on the way, Tom Cruise no longer involved