Scientists have many guesses on what happened to the dinosaurs at the end of the dinosaur age.
One of the most popular ideas is that a killer asteroid hit the earth. Until recently there were a number of theories about the extinction of the dinosaurs, but now recent reports are making the most likely cause of the dinosaur extinction a huge asteroid which hit the Earth with the force of 10,000 hydrogen bombs. It is thought that the asteroid hit part of southern Mexico called the Yucatan peninsula and caused a crater about 125 miles across. The asteroid was probably about 6 miles across and travelling at about 20,000 mph when it crashed and it is thought that it would have caused an earthquake about 1000 times stronger than the worst quakes today. This crash would have thrown a lot of dust into the air causing the sun to be blocked out and making the Earth much colder for a long time.