This Is What Matters When It Comes to Extinction-Level Asteroids

It’s as much about what it hits here on Earth.

Transcript

00:00A giant meteor may have wiped out the dinosaurs hundreds of millions of years ago, but now

00:08experts are saying that the size of the impactor might not matter.

00:12We believe the dinosaurs died because when an asteroid hit the earth, it sent a cloud

00:15of dust into the air.

00:17That cloud blacked out the sun and killed much of the plant life on the planet.

00:20Then the herbivores didn't have anything to eat, and so on.

00:23So the bigger the asteroid, the bigger the dust cloud, the bigger the extinction event,

00:27right?

00:28Well, maybe not.

00:29Scientists found that a 30-mile-wide impact crater, the fourth largest ever discovered,

00:33had no impact on global life.

00:34It just carried on.

00:36Meanwhile, another that was half its size coincided with an extinction period 5 million

00:40years ago.

00:41So what gives?

00:42Apparently, potassium feldspar.

00:44Researchers looked at evidence from all known extinction events over the last 600 million

00:48years, finding that if a meteor hit an area rich in potassium feldspar, an extinction

00:52event would occur.

00:54Potassium feldspar can be found in about 60% of Earth's crust.

00:57But when aerosolized into the atmosphere, it can drastically change the way clouds are

01:01formed, and in turn, Earth's atmosphere in general.