Kold Killer Krater

Really. Planetary scientists have found evidence of a meteor impact in Antarctica much larger and earlier than the one that killed the dinosaurs -- this one wiped out 90 percent of then existing species.

The 300-mile-wide crater lies hidden more than a mile beneath the East Antarctic Ice Sheet. And the gravity measurements that reveal its existence suggest that it could date back about 250 million years -- the time of the Permian Triassic Extinction.

This impact was much bigger than the impact that killed the dinosaurs 65 million years ago. That crater near Mexico is 6 miles wide, while the Antarctic meteor could have been up to 30 miles wide -- four or five times wider.

This event, that scientists call "The Great Dying" was much worse than the extinction that wiped out the dinosaurs. No class of life was spared from the devastation. Trees, plants, lizards, proto-mammals, insects, fish, mollusks, and microbes -- all were nearly wiped out. Roughly 9 in 10 marine species and 7 in 10 land species vanished. Life on our planet almost came to an end.

Hmmm, let's see. The two largest extinctions in Earth's history - almost killing off the human race before it had a chance to start - came from the sky. Does anybody else think we should try to develop a way to divert any other "Doomsday" meteors heading our way?


PB

Comments

Anonymous said…
If 90% of species were wiped out today would anyone notice--assuming we weren't among the missing?

Watched a PBS program last night that indicated only 5% of Earth's species have been discovered. Suspect many are bacteria and marine life, of course, but still....
5:02 PM, February 09, 2007
Anonymous said…
From National Geographic website:

"So far taxonomists have identified less than two million distinct species, mostly mammals and birds.... It's estimated that from ten million to more than one hundred million species are still undiscovered, mainly fish, fungi, microbes, and insects."
5:03 PM, February 09, 2007
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