Perhaps the most consequential day in the Earth’s recent history was when a massive asteroid struck the planet 66 million years ago. It resulted in earthquakes, tsunamis, fireballs raining from the sky, volcanoes, atmospheric heat shocks, wildfires, global winter, and the extinction of 75% of all species on Earth, including the dinosaurs. This video by Kurzgesagt leads us through what happened that day, minute by minute.
This video reminded me of Peter Brannen’s eye-popping description of this event from his book The Ends of the World:
Tags: dinosaurs Earth Kurzgesagt Peter Brannen video“The meteorite itself was so massive that it didn’t notice any atmosphere whatsoever,” said Rebolledo. “It was traveling 20 to 40 kilometers per second, 10 kilometers — probably 14 kilometers — wide, pushing the atmosphere and building such incredible pressure that the ocean in front of it just went away.”
These numbers are precise without usefully conveying the scale of the calamity. What they mean is that a rock larger than Mount Everest hit planet Earth traveling twenty times faster than a bullet. This is so fast that it would have traversed the distance from the cruising altitude of a 747 to the ground in 0.3 seconds. The asteroid itself was so large that, even at the moment of impact, the top of it might have still towered more than a mile above the cruising altitude of a 747. In its nearly instantaneous descent, it compressed the air below it so violently that it briefly became several times hotter than the surface of the sun.
“The pressure of the atmosphere in front of the asteroid started excavating the crater before it even got there,” Rebolledo said. “Then when the meteorite touched ground zero, it was totally intact. It was so massive that the atmosphere didn’t even make a scratch on it.”
Unlike the typical Hollywood CGI depictions of asteroid impacts, where an extraterrestrial charcoal briquette gently smolders across the sky, in the Yucatan it would have been a pleasant day one second and the world was already over by the next. As the asteroid collided with the earth, in the sky above it where there should have been air, the rock had punched a hole of outer space vacuum in the atmosphere. As the heavens rushed in to close this hole, enormous volumes of earth were expelled into orbit and beyond — all within a second or two of impact.
“So there’s probably little bits of dinosaur bone up on the moon,” I asked.
“Yeah, probably.”
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