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Home https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Science https://server7.kproxy.com/servlet/redirect.srv/sruj/smyrwpoii/p2/ Another huge crater was found under the ice in Greenland

Another huge crater was found under the ice in Greenland



The gladiator has discovered another huge impact crater under more than a mile of ice in Greenland. This is on the heels of the discovery in November 2019 on a crater in the same area under the Hawaii glacier. The opening in November is the first crater of its kind found under the ice of the Earth.

The two craters are only 183 km (114 miles) apart. The November crater is 30.5 km (19 miles) wide and the new one is 35.4 km (22 miles) wide. If the new one can be categorically confirmed as a crater, it will be the 22nd largest of the Earth.

Joe McGregor is the gay scientist who discovered this new crater. He works at NASA's Space Center in Greenbelt, Maryland. He also participated in the first discovery. The discovery of this new crater was published in an article in Geophysical Research Letters on Feb. 1

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The geology of the Earth's polar regions is not well understood. Thick sheets of ice cover rock and surface features. But thanks to aero-geophysical data and satellite data, scientists are beginning to get a better idea of ​​it. Finding craters is of great interest because they can have such a global impact on climate history.

A previous survey in 2015 looks at the inventory of impact craters and concludes that finding more craters of this size is incredible, but not impossible. This study says that finding more craters larger than 6 km is unlikely (although we will probably find 90 more craters between 1km and 6km in width.) This conclusion is based largely on speeds of erosion

But deep under the ice, the rates of erosion are different. Will we find even larger craters under the ice? "In an interview with NBC News, McGregor said:" Once we know from Hawaii that there may be craters under the ice sheets, it is very easy to find the next one. using an ensemble of publicly available NASA data. "

  Cracters under the ice in Greenland. Earlier, the open crater Hiawatha is in the upper left corner, and the newly opened crater is near the lower right corner. Image Credit: J.A. MacGregor et. Al. 2019.
Crayfish under the ice in Greenland. Earlier, the open crater Hiawatha is in the upper left corner, and the newly opened crater is near the lower right corner. Image Credit: J.A. MacGregor et. Al. 2019.

Scientists use data on altitude, texture and topography, as well as magnetic and gravitational data to look for more craters. According to MacGregor, it was not difficult to identify the potential second crater. As the two craters are so close to each other, the team wondered if they were from the same event. Although they are of similar size, there are significant differences. The second crater looks more eroded, and the ice over it is much less upset. In the paper, the authors say: "The statistical analysis of the frequency of two unrelated but close major impacts shows that it is unlikely, but it is not impossible that this pair is not related."

Asteroids are known to exist in double pairs. About 15% of the Earth's asteroids are binary. So it is possible that the pair of craters are twins. However, studies of asteroid populations near the Earth have not found double pairs of asteroids of the same size. From a statistical point of view, these two are unlikely to be couples.

  An image of the underground topography of the area where both shooters were found. Image Credit: J.A. MacGregor et. Al. 2019
Image of the post-glacial topography of the area where both shooters were discovered. Image Credit: J.A. MacGregor et. Al. 2019

There are two more pair of craters on the Earth: the first couple are Bolts and Cologne craters in Ukraine, the second is the craters of Clearwater Lakes in Quebec, Canada. It is believed that these couples are twins of the same events, but dating argon and other techniques reveal great age differences between them. The Clearwater Lakes Craters in Quebec, Canada. It is believed that they were caused by a pair of binary asteroids, but testing revealed a great difference in their age. Image Credit: From the photos of NASA Earth Observatory by Jesse Allen and Robert Simman using data from Landsat 8. "class =" wp-image-141504 "srcset =" https://www.universetoday.com/wp-content/uploads /2019/02/Clearwater_Lakes_2013180_labels.jpg 720w, https://www.universetoday.com/wp-content/uploads/2019/02/Clearwater_Lakes_2013180_labels-250×167.jpg 250w, https://www.universetoday.com/wp-content /uploads/2019/02/Clearwater_Lakes_2013180_labels-580×387.jpg The Clearwater Lakes craters in Quebec, Canada, are believed to be caused by pair of binary asteroids, but testing revealed a big difference in their age Image Credit: From NASA Earth Observatory photos by Jesse Allen and Robert Simmon using Landsat 8 data

Same techniques can not be used to determine the age of these two new craters under the ice, but much of the study's detailed data shows that they are not of the same age, for example, the ice ice appears to be a different age for each crater. During the first crater, the ice seems to be no older than 12,800 years, while the new ice crater appears to be at least 79,000 years old.

This discovery is still awaiting confirmation, but morphology looks like a crater of impact. The question is, how much more of these craters we find buried under the ice on Earth?

Will we find others and will it be related to the changing climate in Earth's history? Will it be related to extinction, such as the impact of Chixoulub, which has caused so many dinosaur problems? Who knows. But with improved remote sensing technology, we'll find them if they're there.

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