Under Greenland's ice, the massive 31-kilometer-wide Hiawatha impact crater is submerged to a depth of one kilometer. Of the 200 or so that have been discovered so far, this is one of the largest. For years, scientists have speculated that it was caused by an asteroid or comet that collided with Earth 13,000 years ago, long before humans had arrived on the globe. Danish and Swedish scientists, on the other hand, determined that no one could have felt the impact of the cosmic collision. Due to the fact that it occurred before we arrived. The Greek one was left behind by an asteroid that crashed 58 million years ago, just a few months after the one that killed out the dinosaurs.
Hiawatha crater in northwestern Greenland was discovered in 2015 by researchers from the GLOBE Institute at the University of Copenhagen. Since then, there has been a lot of conjecture concerning the crater's age. Could a small ice age lasting more than a thousand years have begun because of anything barely 13,000 years old?
No, new sand and rock samples from the crater demonstrate that this is not the case. The Hiawatha impact crater, on the other hand, dates back millions of years. 58 million years ago, a meteorite about 10 kilometers long struck what is now Mexico's Yucatan province, leaving a much larger crater, Chicxulub, about 200 meters in diameter, and wiping out much of the life that existed at the time, including the dinosaurs. Chicxulub was about 8 million years old when it fell.
This was a particularly difficult problem to solve, so it's heartening to see that two separate labs in Denmark and Sweden have arrived at the same conclusion using two distinct dating methods. Michael Storey, the Natural History Museum of Denmark's director, says he is confident that the true age of the crater, which is significantly older than previously assumed, has been established.
"Knowing his age now is amazing. Since we discovered the crater seven years ago, we've been trying to figure out how to date it. Nicolaj Krog Larsen of the GLOBE Institute has made repeated trips to the area since then to gather samples.
Sand and lasers are a match made in heaven
When asteroid Hiawatha blasted into Earth's surface, unleashing several million times more energy than an atomic bomb, there was no substantial ice sheet covering northeastern Greenland. Back then, the Arctic was covered with temperate rainforest, wildlife abounded, and daytime temperatures hovered about 20 degrees Celsius.
Upon impact, the asteroid left a crater thirty-one kilometers wide and one kilometer deep, large enough to house the whole city of Barcelona. The Hiawatha Glacier in northwestern Greenland is where the crater is now. Researchers were able to obtain sand and rock that had been burned by the impact 58 million years ago from rivers flowing from the glacier.
A laser was used to burn the grains of sand until argon gas was released at the Natural History Museum of Denmark, while the mineral zircon was used to date the rock samples at the Swedish Museum of Natural History using uranium-lead dating.
"We were all taken aback by the new age's tenacity. According to Gavin Kenny of the Swedish Museum of Natural History, "it will enable us explore the possible effects on climate during a critical point in Earth's history."
In spite of its lower size than the Chicxulub impact crater, the Hiawatha impact crater has the potential to have a devastating effect on the surrounding area, as well as on the climate and plant and animal life. Chicxulub had been a terrible event, but the Earth had begun a warming trend that would run for nearly 5 million years at the time of the impact.
There is currently no conclusive evidence that the Hiawatha impact changed the global climate. To better understand how an impact affected our planet's climate and, ultimately, our way of life, the research team may now begin testing numerous possibilities.
