Wednesday , December 2 2020

They find under the ice of Greenland the crater that produces an asteroid



Only in its dimensions is it historical. It is among the 25 largest found on the planet

They find under the ice of Greenland the crater that produces an asteroid

Map of the rocky topography under the ice sheet and the ice-free land around the impact crater / Danish Natural History Museum

In 2015, geo-chemist at the University of Copenhagen, Kurt Coeur, noticed a strange depression under the glacier Gryalaya Hiawaha. One study reveals that it has just opened a crater with blows over 30 km. Its origin: an asteroid.

Only by its size the crater is now historic, being one of the 25 largest on the Earth. However, the history and origin of this is what really matters science. When and how did we have a huge influence on the continental ice in Greenland?

It turns out that not so long ago, nor at least in terms of the history of our planet, as a meteorite, a wide kilometer wide, created it.

unexpected circumstances

As Kjær explained: extraordinary discoveries require unusual evidence. We have more than a decade of radar data, a technique in which to look at the ice with which we build a map of topography of the glacier. Thus, in 2015, we encountered the huge circular depression under the layer. We immediately realized that this was something special but at the same time it was clear that it would be difficult to confirm the origin of the depression.

continue the studies

Since then, the past three years have been working and studying the area by taking pictures and using a new radar developed by the Kansas University.

You can see the rounded construction of the edge of the ice sheet, especially when you fly high enough. For the most part, the crater can not be seen through the airplane window. It is strange that no one ever thought, "Hey, what is this semicircular feature there?" The plane is fine and hard to see unless you know it already.

By using low-angle satellite imagery that highlights the hills and valleys in the ice sheet's ground, you can actually see the circle of the entire crater in these images.

Kjær also explained that the alien reminded him from the very beginning of the Cape York meteor who had crashed in Greenland about 10,000 years ago, who left huge pieces of iron scattered in the same region as the glacier, could he have a connection with him? strike event?

Recently published work does not come to the conclusion that this is the case, but they present a number of convincing lines of evidence suggesting that the crater was probably created over the past 100,000 years.

Geochemical analysis of sludge near the glacier also shows evidence of impact processes showing the presence of iron. These include quartz, which is usually located in impact areas, and glass that is made of silica at the base due to the high heat of impact.

In terms of age, scientists believe that the evidence they provide is strong enough to think that this has happened before Greenland is covered with ice.

It is difficult to be wrong if we think that the range covered 3 million years ago only 12,000 years ago, towards the end of the last ice age. According to Kjell: I think this happened when Greenland was covered with ice and that would melt a significant amount of melt. This melted water will go south to a sensitive point in the climate system.

they want to know the exact date of impact

However, they try to break through ice to get rock samples that can be used for dating and the exact date of impact.

Crater as large as the window he opened for science. His study raises any questions, such as the possibility of rain from asteroids or the fact that the impact has triggered global cooling, which could significantly affect the ancient population of the people.


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