A Massive Impact Crater Has Been Detected Beneath Greenland's Ice Sheet (gizmodo.com)

An anonymous reader quotes a report from Gizmodo: An unusually large asteroid crater measuring 19 miles wide has been discovered under a continental ice sheet in Greenland. Roughly the size of Paris, it's now among the 25 biggest asteroid craters on Earth. An iron-rich asteroid measuring nearly a kilometer wide (0.6 miles) struck Greenland's ice-covered surface at some point between 3 million and 12,000 years ago, according to a new study published today in Science Advances. The impact would've flung horrific amounts of water vapor and debris into the atmosphere, while sending torrents of meltwater into the North Atlantic -- events that likely triggered global cooling (a phenomenon sometimes referred to as a nuclear or volcanic winter). Over time, however, the gaping hole was obscured by a 1,000-meter-tall (3,200-foot) layer of ice, where it remained hidden for thousands of years. Remarkably, the crater was discovered quite by chance -- and it's now the first large crater to be discovered beneath a continental ice sheet.

Comments

Date Range

[Anonymous Coward]

That's quite the range of ages: two orders of magnitude. Not an impressive estimate.

Re:Date Range

[greythax]

This post getting modded up to +4 interesting is a perfect example of how slashdot has jumped the shark. Or at the very least proof of mod bots.

range

[segwonk]

Isn't 12,000 --3,000,000 years a pretty big window?? Or is that par for the course?