Why do many people think that an asteroid had to do with the extinction of the dinosaurs?

Question

Argue both pro and con. Thanks!

Answer 1

Well, dinosaurs had been around for 135 million years. They lived in most parts of the world, then very suddenly they all died out. This suggests some sort of major disaster. About this time a thin layer of sediments rich in iridium was laid down. Asteroids are rich in iridium but it is rare in the Earth's crust. A likely asteroid crater is one in the Caribbean Sea. An asteroid impact would explain a whole lot of observations. Dust thrown up would darken the sky for months, slowing photosynthesis and causing a food shortage, which selectively kills off the largest animals. This would explain why dinosaurs died but smaller species survived.

Answer 2

Because there are several good reasons...

1) The very large crater (examine a surface map of the Gulf of Mexico);

2) The iridium layer right at the 65,000,000 year level;

3) The fact that the large crater dates from the same time.

Iridium is only about 1000 times more prevalent in asteroids than it is inthe Earth's crust, and there is a uniform layer of it at the 65,000,000 year boundary in the Earth's crust.

Combine that with fossil evidence above and below that boundary (called the K-T Boundary), and you have a planet killer striking the Earth.

Answer 3

Hi. Iridium is an element rare on Earth but more common in asteroids. There is a layer of this in the Earth's crust dating just as the dinosaurs went extinct.

Answer 4

in geology records, as you dig down, there is something called the KT boundary. this boundary can be traced back to the dinosaurs age. and in this layer of rock there is a high level of the chemical iriudium. this can be trace to space rocks, asteroids. so the theory goes that this iriduim had to come from space. once the asteroid plowed into the earth, the amount of dirt and debris thrown into the skies of earth, thus blocking out the sunshine. and killing vegetation and other animals that eat on the vegetation.

Answer 5

I saw it on TV. there is a thin layer of elements found in asteroids under other layers of earth that got there about the same time the dinosaurs died. we take a big hit about every 25,000,000 years. what time is it?

Answer 6

I think an asteriod had to do with the extinction of the dinosaurs.

Answer 7

Scientific evidence.

Answer 8

Craters and other geological evidence, timing, the effects it would have on the planet and dinosaurs, etc.

Answer 9

Some really big holes were found on the ground.