A giant impact crater in Greenland formed several million years after the dinosaurs died out. This puts an end to speculation that the meteorite fell after the appearance of people.
The authors of the new work collected grains of sand and stones from the impact crater Hiawatha and found out that it is much older than the moment when people began to inhabit the Earth. Its age is approximately 58 million years.
Earlier, researchers from the GLOBE Institute at the University of Copenhagen discovered the Hiawatha impact crater in northwestern Greenland. They did not know when the meteorite fell, so this fact became the subject of a lot of controversy and theories. It was not known if an asteroid could have crashed into Earth just 13,000 years ago, when humans had long inhabited the planet, and if its impact could have caused the nearly 1,000-year period of global cooling called the Younger Dryas.
The authors of the new work found that these events are not related:
Understanding when the crater formed was a very difficult task. Two laboratories in Denmark and Sweden, using different dating methods, came to the same conclusion. Therefore, I am convinced that we have determined the actual age of the crater.
Michael Storey of the Natural History Museum of Denmark.
The authors studied the crystals of the mineral zircon – with the help of them you can learn about various events in the history of the Earth. Dating zircon crystals is one of two methods that the researchers have used.
Scientists believe that the fall of the Hiawatha meteorite caused a lot of destruction and may even have affected the climate. But so far, there is still no conclusive evidence that this event disrupted the global climate. The dating of the crater allows researchers to test various theories and better understand how the meteorite influenced the history of the Earth.