Antarctica Got Blasted by a Powerful ‘Airburst’ Event 430,000 Years Ago

Asteroids that smash directly into Earth’s surface can cause extensive damage, but, as new evidence uncovered in east Antarctica suggests, asteroids that explode on entry can be equally devastating.

Super tiny black balls made from igneous rock are evidence of a calamitous event in the Sør Rondane Mountains of Antarctica some 430,000 years ago, according to research published today in Science Advances. An object measuring somewhere from 330 to 490 feet (100 to 150 meters) wide entered our planet’s atmosphere, but instead of crashing on the surface and forming a crater, the object exploded prior to reaching the ground.

Now, that might sound like a good thing, but as geochemist and planetary scientist Matthias van Ginneken pointed out in an email, this “airburst” event still managed to ravage the icy Antarctic surface. When the object exploded, it produced a “cloud of superheated gas” that resulted from the “vaporization of the asteroid during atmospheric entry,”

explained van Ginneken, the lead author of the study and a research associate from the University of Kent in the United Kingdom. This cloud, packed with tiny molten particles and scorching-hot vapor, traveled as a jet and at hypervelocity speeds, as “it did not have time to lose momentum upon reaching the Antarctic ice sheet,” he said. When this jet reached the surface, it was still moving at speeds approaching several miles per second.

No crater was formed from this event, but the contact area—the region that came into contact with the cloud of superheated gas—was blasted into a hellscape, as temperatures reached several thousand degrees Fahrenheit. READ THE FREE ARTICLE.