The first impact crater on the Moon formed more than 4.32 billion years ago, 120 million years earlier than previously thought. This is stated in a new international study led by astronomers at the University of Manchester.
As reported by Phys.org, the new study significantly changes our understanding of the formation of the Moon. It is known that in the early stages it was subject to intense bombing.
Asteroids and meteorites have crashed into the Moon’s surface over hundreds of millions of years, leaving behind impact craters of varying sizes. Until recently, it was believed that the most intense bombardment occurred between 4.2 and 3.8 billion years ago, that is, in the first 500 million years of the Moon’s existence.
However, as part of a new study, the age of the Aitken impact basin at the South Pole has been revised. The authors of the work claim that they were able to determine it with a high degree of precision thanks to the study of a lunar meteorite discovered several years ago in Algeria. Researchers believe the impact basin formed 4.32 billion years ago, 120 million years before the Moon was thought to have been bombarded by space objects.
The discovery not only expands the chronological scope of said bombardment, but also indicates that the process of collisions of asteroids and meteorites with the surface of the Moon was slower than expected and gradually increased its activity.
The study also confirms the generally accepted belief that the Aitken Basin is the oldest confirmed asteroid impact site on the Moon. It is located on the opposite side of the Earth’s satellite and extends over 2,000 kilometers.