The extinction of dinosaurs was caused by dark matter. At present, it is only an unconfirmed statement, but this statement has caused controversy in academic circles. A physics professor at Harvard University suggested that the sun rotates in a wavy shape in the Milky Way, and there is very large dark matter in the wavy central region. The sun is influenced by the gravity of dark matter, and it will fluctuate greatly every time it passes. This kind of fluctuation will lead to the change of comet orbit, which will hit the earth, and the final result will be the extinction of dinosaurs. So he concluded that the existence of dark matter led to the extinction of dinosaurs.

Professor Shude Mao, an astrophysicist in Tsinghua University, China, disagrees with this statement put forward by Harvard University physics professor. He believes that dark matter is illusory and has little impact on the earth. Why is dark matter illusory? Because the density of dark matter is very, very low, almost negligible.

Dark matter has no effect on the revolution or autobiography of the earth. The mass of dark matter is very small, which is one tenth of the total mass of the sun. And in radius of the earth, the quality will be very, very small. It is too small for the mass of the earth to be detected even by current observation methods.

Shude Mao did not think that the extinction of dinosaurs was caused by dark matter. He thinks this view is even more wrong, but there is no way to prove it at present. Shude Mao believed that the extinction of dinosaurs was caused by the impact of celestial bodies, because scientists found a special celestial element iridium in a fossil layer on the earth, which is very high in composition and does not exist on the earth, but scientists have seen it on asteroids many times. By calculating the age of this fossil layer, the scientist found that the existence time of this fossil layer was almost the same as that of the dinosaurs on the earth, so he thought that the reason for the extinction of dinosaurs was caused by the influence of celestial movement.