Particles of a Meteor Explosion From 430,000 Years Ago Found Hidden in Antarctic Ice

Approximately 430,000 years ago, a meteorite exploded over Antarctica.

The only reason we know about it now is because scientists have just found tiny, once-molten particles of space rock that have been hidden away in the ice ever since.

Based on an analysis of those particles, the event was an unusual one - not quite powerful enough to produce an impact crater, but nor was it a lightweight. The jet of melted and vaporized material that blasted from the mid-air explosion would have been more hazardous than the Tunguska event that flattened a Siberian forest in 1908.

Although crater-producing impacts are fairly rare, rocks entering and exploding in Earth's atmosphere are not. They're called bolides, and NASA has logged 861 of them since 1988 at time of writing. Superbolides - those like the Chelyabinsk meteor in 2013, or the Kamchatka meteor in 2018 - occur a few times a century.

Airburst events more powerful than Tunguska are rarer still, but they're still thought to have been more common than impact cratering events throughout Earth's history. This is sobering, according to a team led by cosmochemist Matthias van Ginneken of the University of Kent, UK.

"While touchdown events may not threaten human activity if occurring over Antarctica," he said, "if it was to take place above a densely populated area, it would result in millions of casualties and severe damages over distances of up to hundreds of kilometers." Read the free article.