What Determines if an Asteroid Could Wipe Out Life on Earth?.mp4

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 experts

00:09are saying that the size of the impactor might not matter. We believe the dinosaurs died because

00:13when an asteroid hit the earth it sent a cloud of dust into the air. That cloud blacked out the sun

00:18and killed much of the plant life on the planet. Then the herbivores didn't have anything to eat

00:22and so on. So the bigger the asteroid the bigger the dust cloud the bigger the extinction event

00:26right? Well maybe not. Researchers found that a 30 mile wide impact crater the fourth largest ever

00:32discovered had no impact on global life. It just carried on. Meanwhile another that was half its

00:37size coincided with an extinction period 5 million years ago. So what gives? Apparently potassium

00:43feldspar. Researchers 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 event would occur.

00:53potassium feldspar can be found in about 60 percent of earth's crust but when aerosolized into the

00:58atmosphere it can drastically change the way clouds are formed and in turn earth's atmosphere in general.