Saturday , May 8 2021

A Greenland crater under an ice field reveals asteroid impact: a study



When you think of a massive asteroid colliding with the Earth, the dinosaur extinction is observed 65 million years ago.

The prevailing theory is the Chickulub crater, 115 miles wide and located on the Yucatan Peninsula in Mexico, was a land of a deadly asteroid that crashed into the world for tens of millions of years and launched a chain of events that killed dinosaurs, Science Daili reported.

Now, a study published in Scientific Advances magazine reveals the discovery of another asteroid crater that probably hit a relatively recent history of the Earth, although this is not quite as great as the catastrophic crater found in Mexico. And its true effect is still unknown.

This new crater was found beneath the iceberg of Hiavath Glacier in Greenland, according to a study. 19 kilometers wide, bigger than Paris or Washington, D.C. – and he probably hit the recent history of the Earth how he estimates how much is preserved, the study says.

"Until now, it was not possible to get to know the crater directly, but its condition strongly indicates that it was formed after the ice began to cover Greenland, so it is younger than 3 million years ago and maybe almost 12,000 years ago – at the end of the last ice age, written by the author Kurt H. Kjær in a statement from the University of Copenhagen.

The discovery was made possible thanks to NASA's IceBridge operation, an initiative to scan "Polar Ice Changes" and publish this information to the public for map review, according to NASA. Researchers at the University of Copenhagen, the Center for Geo Genetics at the Natural History Museum of Denmark, have helped to study NASA data, revealing the shape of what appears to be a huge crater hidden under the ice in Greenland in July 2015.

NASA's glaciologists Joseph MacGregor worked with researchers after their initial discovery, watching "radar measurements" of a possible crater that took the research plane from the Alfred Vegener Institute in Germany.

And what did they find?

"Extremely circular rings, central lift, annoyed and unhindered glueing of the ice and basal remains," MacGregor said in a press release.

In other words, the evidence that this really a crater caused by asteroid collisions is "all there," MacGregor said.

The researchers also found a channel in which some of the melt water in the glacier flowed freely – and it was used to collect different stones to seek more evidence of a major impact.

They found shocked quartz and glass, which are formed after a major collision, as Gizmodo remarked. National Geographic reported that it is estimated that the asteroid will be about three quarters of a million miles across the globe with a high weight of up to 12 billion tons.

In the Geological Museum of Copenhagen, there is a 20-tonne meteorite, not far from the crater, which led researchers to the theory of whether these two are related, the study said.

Kjær told National Geographic that although he was not involved in this work, his findings could eventually help stimulate the hypothesis of the impact of younger droplets, which says that huge animals like mammoths have died during the Ice Age due to high-impact fires .

But there are still long ways that before this argument can be supported, Kjær warned the magazine.

"This can trigger a lot of discussion, and we have to find out," he said, according to National Geographic. "We will not know until we have a real meeting."

Nicolaj K. Larsen, co-author of the study, told Gizmod that researchers are already trying to figure out how to get a more specific date of impact.

"We are currently trying to find out ideas about how to influence the impact," she said on Tuesday. "One idea is to break ice and get samples that can be used for numerical administration."


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