its diameter more than 31 kilometers ranks it among the 25 impact craters larger land, according to the findings of an international team of researchers consisting of experts from Denmark, Germany and United States.
The crater was formed when a one kilometre wide iron meteorite crashed in the North of Greenland at a date still to be determined, and since then it had been buried under the ice of the glacier Hiawatha.
“The crater is exceptionally well preserved and that’s surprising, because the ice of the glacier is an incredibly efficient erosive agent that would have quickly removed traces of the impact”, explained Professor Kurt H. Kjær, Geogenetica Centre of the Museum of Natural history of Denmark.
“That means that the crater should be pretty young from a geological perspective,” he added.
The researchers estimate that the crater was probably formed during the Pleistocene, perhaps only about 12,000 years ago, towards the end of the last was glacial, but more studies are needed to be able to specify the date.
The first indications of the existence of the crater dates back to July 2015, when researchers inspected a new map of the topography under the Greenland ice cap and noticed the presence of a huge circular depression, previously not detected.
They decided then to send an aircraft of the German Institute Alfred Wegener to fly over the glacier Hiawatha and map the area with a new and powerful radar developed by the University of Kansas (USA) ice.
That next-generation radar “exceeded all expectations and imagined depression with amazing detail,” said Joseph MacGregor, a glaciologist from NASA who also participated in the research.
To confirm the findings of the radar, were conducted further studies of the rock near the foot of the glacier and of sediments via a meltwater channel which detected the presence of quartz, glass and other items related to the impact the meteorite.
The next step in the research is accurately dating the time of impact and determine if it affected and how the Earth’s climate.