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Radar unveils a second potential impact crater among Greenland ice science



NASA SCIENTIFIC VISUALIZATION STUDIO

2, 2019, 5:30 pm

Only a few months after an impact crater the size of Washington, DC buried beneath the ice of northwest Greenland has been uncovered a team of scientists discovers that it has company: a major depression 180 kilometers away This can also be an asteroid or comet impact crater.

Several years ago, after explorers discovered the first crater under the Hiawatha glacier in Greenland, researchers began to search satellite records and ice-penetrating radar profiles for other circular deformations. Profiles from NASB's IceBridge research flights revealed a 36-kilometer, bowl-shaped dip surrounded by a rim, with a cluster of elevated peaks in the center reminiscent of the ascent found after an asteroid or comet on the surface of the earth ,

In Hiawatha Crater, the basin has not produced any shocked quartz crystals, which are considered the best evidence of extraterrestrial impact. The basin appears eroded and filled with ice, older than the Hiawatha crater, suggesting that a crater is likely to have a different impact, the researchers write this week in Geophysical Research Letters . 19659004] Although this may seem like an implausible coincidence, other unrelated pairs of impacts were found in Ukraine and Canada. The rate of cosmic collisions required to achieve such a coincidence is possible, as recent studies have shown an increase in the bombardment of the Earth by extraterrestrial objects in the last 300 million years.


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