19 Mile-Wide Hiawatha Crater in Greenland Older Than Previously Thought, Ending Speculation the Meteor Caused the Ice Age

The 19-mile-wide Hiawatha crater in Greenland was formed when a huge meteorite struck Earth about 58 million years ago, making it eight million years older than previous estimates. Scientists used radioactive carbon dating to determine the age of the rock samples from the impact site.

MailOnline reported that the argon gas and crystals of zircon from the rock samples, which act as time capsules, allowed scientists to discover when the space rock struck Earth. It could mean that it did not cause the Ice Age and that early humans did not witness it. Researchers hope to know how the impact has changed the Earth's climate during that time.

Dating Rock Samples From Hiawatha Crater

The Hiawatha crater is hidden under the thick ice sheet in Greenland in what scientists believe as a scar of an asteroid impact that perhaps dated thousands of years ago, young enough to be witnessed by early humans. Scientists first suspected of the crater's existence in 2015 after examining NASA's two-decade worth compilation of the sub-ice topography in the country, the space agency said.

Subsequent research has confirmed its existence, and after several years of additional data gathering, researchers from the Natural History Museum of Denmark, the GLOBE Institute at the University of Copenhagen, and the Swedish Museum of Natural History in Stockholm found that the crater is already 58 million years old.

According to a statement from the University of Copenhagen, the team of researchers independently sampled the rocks from the crater and dated them to identify the age of the impact.

The team from the Natural History Museum of Denmark analyzed the sands by heating them with a laser until the samples released argon gas. On the other hand, the rock samples were analyzed at the Swedish Museum used uranium-lead dating on the mineral zircon. The teams settled that the impact happened 58 million years ago.

The paper, titled "A Late Paleocene Age for Greenland's Hiawatha Impact Structure," published in Science Advances, described the full details of the research of dating the Hiawatha crater.

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How Did the Impact Crater Affected Earth's Climate?

Knowing the true age of the impact crater helps scientists plan to investigate how the impact of the meteorite has changed the climate on Earth, Space.com reported. Researchers pointed out that before the impact, Greenland was not covered in ice sheets but rather with rainforests.

They believe that the asteroid that created the crater, which is estimated to be several million times stronger than an atomic bomb, certainly would have annihilated a large part of Greenland. However, they are unsure of its impact on the climate, unlike the Chicxulub crater in Mexico that eradicated the dinosaurs 66 million years ago.

The scientists have expressed their plans of continuing their research on the Hiawatha crater in hopes of understanding its effect on the climate.

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