Buried beneath the Hiawatha Glacier is an ancient 31-kilometer-wide impact crater, left when an iron asteroid 1.5 kilometers across slammed into what is today Greenland, possibly within the past 100,000 years reports Paul Voosen in Science. Big enough to swallow Washington, D.C., the crater was detected by Kurt Kjær, a geologist at the Natural History Museum of Denmark in Copenhagen, and 21 co-authors reported this week in Science Advances. The crater was left when an iron asteroid 1.5 kilometers across slammed into Earth, possibly within the past 100,000 years.
Though not as cataclysmic as the dinosaur-killing Chicxulub impact, which carved out a 200-kilometer-wide crater in Mexico about 66 million years ago and was ground zero of the Cretaceous extinction event, the Hiawatha 31-kilometer-wide impact crater, too, may have left an imprint on the planet’s history. The timing is still up for debate, researchers on the discovery team believe the asteroid struck at a moment, roughly 13,000 years ago, as the world was thawing from the last ice age. That would mean it crashed into Earth when saber-toothed tigers and other megafauna were in decline and humans were trekking across the Bering land bridge on their epic migration into North America.
Image credit above: NASA Scientific Visualization Studio.
CREDITS: (GRAPHIC) C. BICKEL/SCIENCE; (DATA) UMN POLAR GEOSPATIAL CENTER; ICEBRIDGE BEDMACHINE GREENLAND/NASA NATIONAL SNOW AND ICE DATA CENTER