How Asteroids Really Killed The Dinosaurs

In 1980, Nobel Prize-winning physicist Luis Walter Alvarez and his geologist son Walter published a theory that a historic layer of iridium-rich clay was caused by a large asteroid colliding with Earth. The instantaneous devastation in the immediate vicinity and the widespread secondary effects of an asteroid impact were considered to be why the dinosaurs died out so suddenly.

Asteroids are large, rocky bodies that orbit the Sun. They range from a few to hundreds of metres in diameter. Any fragment of an asteroid that survives landing on Earth becomes known as a meteorite.

Around 75% of Earth's animals, including dinosaurs, suddenly died out at the same point in time. So how was it all caused by a rock hurtling into the coast of Central America?