May 13, 2021

This is the crater of a giant meteorite

This is the crater of a giant meteorite

A team of researchers has discovered a giant crater, greater than the surface occupied by Paris, that had remained hidden under a thick layer of ice in the north of Greenland and that was formed by the impact of an iron meteorite, according to publishes the Science Advances magazine and pick up Efe.

Its diameter of more than 31 kilometers places it among the 25 largest impact craters on Earth, according to the findings of an international team of researchers formed by experts from Denmark, Germany and the United States.

The crater was formed when a one-kilometer-wide iron meteorite crashed in northern Greenland on a date yet to be determined and since then it had remained buried under the ice of the Hiawatha glacier.

"The crater is exceptionally well preserved and that is surprising, because the ice of the glacier is an incredibly efficient erosive agent that would have quickly eliminated the traces of the impact," explained Professor Kurt H. Kjaer, of the Geogenetics Center of the Natural History Museum of Denmark.

"That means the crater must be quite young from a geological perspective," he added.

The researchers estimate that the crater probably formed during the Pleistocene, perhaps only about 12,000 years ago, towards the end of the last ice age, although more studies are needed to be able to specify the date.

The first signs of the existence of the crater date back to July 2015, when researchers they inspected a new map of the topography below the Greenland ice sheet and noticed the presence of a huge circular depression, previously not detected.

They decided to send a research aircraft from the German institute Alfred Wegener to fly over the Hiawatha glacier and map the area with a new and powerful ice radar developed by the University of Kansas (USA).

That state-of-the-art radar "exceeded all expectations and imagined depression with amazing detail," said Joseph MacGregor, a NASA glaciologist who also participated in the investigation.

To confirm the radar findings, further studies of the rock near the foot of the glacier and of sediments carried through a channel of melt water were made that detected the presence of quartz, glass and other elements related to the impact of the meteorite.

The next step in the investigation is to accurately date the moment of the impact and determine if and how it affected the climate of the Earth. EFE


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