Asteroid 'wiped out' dinosaurs
Dinosaurs were wiped out by a giant asteroid the size of the Isle of Wight, a group of experts have concluded.
There have long been two main theories on why dinosaurs became extinct.
One is that a giant asteroid in Mexico wiped them out, and the other is that lots of volcanic 'super eruptions' in India caused them to die out.
Now a group of 41 scientists have studied loads of evidence and they now believe that the asteroid theory is the right one.
The asteroid would have hit the Earth with the power of a billion atom bombs.
It was so strong that it would have caused huge fires, earthquakes measuring more than 10 magnitude, landslides and giant waves, called tsunamis.
A T-Rex skeleton at the Natural History Museum
One of the scientists said: "The asteroid was about the size of the Isle of Wight and hit Earth 20 times faster than a speeding bullet.
"The explosion of hot rock and gas would have looked like a huge ball of fire on the horizon."
Dinosaurs lived on Earth around 65 million years ago, but they were totally wiped out during a mass extinction.