China News Service, Beijing, July 22 (Reporter Sun Zifa) The formation of many craters on the surface of the moon has attracted much attention. The latest planetary scientific research believes that the moon experienced an asteroid rain 800 million years ago.
A new research paper published in the international academic journal "Nature-Communication" under Springer Nature stated that about 800 million years ago, the moon was bombarded by meteoroids (smaller asteroids). Based on the collision probability, the study shows that the total mass of these meteoroids is about 30 to 60 times that of the meteorite that caused the Chicxulub impact on Earth before the glacial period (about 720 million to 635 million years ago).
The paper stated that the process of erosion and surface renewal on the earth made it difficult to study ancient meteoroid impacts and to determine their dates. However, there is another way to understand these impacts-study the craters on the moon, because on the moon, the effects of weathering and erosion are greatly reduced.
The corresponding author of the paper, Kentaro Terada of Osaka University, Japan, and colleagues used data from the lunar probe Kaguya to estimate the formation time of 59 craters with a diameter of more than 20 kilometers on the surface of the moon. They found that 8 of these craters were formed at the same time, including Copernicus crater. Based on the radioactive dating results of the material released from the Copernicus crater and the data obtained from the impact glass chondrules (glass beads formed by meteorite impacts) of some Apollo missions, they concluded that the moon is about 800 million years old. I experienced an asteroid rain before.
The author speculates that since asteroid rain has occurred on the moon, a similar event must have occurred on the earth. They used the crater scaling law and collision probability to show that an asteroid with a mass of 400 to 500 million kilograms collided with the earth. (Finish)