Our natural satellite was formed about 4.4 billion years ago. Since then, this body has seen a lot. Now, scientists have discovered this, while examining rocks collected during several Apollo missions. About 100 million years after the formation of the silver ball, a very large “igneous event” occurred..
Scientists downloaded it earlier lunar rock samples They isolated more than 500 zircon grains. zircon They are formed during the solidification of magma, so thanks to them you can delve into the geological past. Most of the samples date back about 4.33 billion years, which means that a major cosmic event must have occurred during this period.
A more detailed analysis showed that this one This mysterious phenomenon lasted for up to 4 million years. (plus/minus 500,000 years). Researchers believe this was the cause. A large asteroid impact created the Antarctic-Aitken Basin..
The giant structure is located on the far side of the Moon. It is 2,500 km in diameter and an incredible 13 km deep. The crust here is only 30 km thick, while the average thickness of the entire crust is about 50 km. Interestingly, the bottom of the crater has a different geochemical composition than the surrounding areas.
In our research, we found interesting evidence of a serious, potentially dangerous Global igneous event on the moon 4.338 billion years ago“By carefully dating lunar zircon crystals from the Apollo missions, we have discovered an amazing concentration of zircons that are about 4.338 billion years old,” said Dr. Melanie Barboni of Arizona State University.
She also added: “Such a strong impact would have extracted material from the Moon’s mantle from great depths. We suggest that the zircons we dated may have crystallized in the layer.” shock alloyAs the surface cooled, subsequent impacts may have spread these zircons over almost the entire surface. moon.
Previous research suggests that There is a very large “excess mass” under the South Pole-Aitken Basin.Which can extend to a depth of more than 300 kilometers. According to calculations, the mysterious structure weighs up to 2.18 × 1018 kg. Experts suggest that it may be the remains of the metal core of a large asteroid that hit our satellite.
– A blow of this size It would have a major impact on the evolution of the lunar crust and mantle. Our findings also have interesting implications for the state of the early solar system more than 4.3 billion years ago. An impact of this magnitude suggests that the solar system was still in existence at that time. MovingDr. Barboni explained that large objects continued to collide with planets and moons.
With this in mind, one can expect that The Earth was also bombarded by space rocks during this period.. Plate tectonics and surface processes have effectively erased their traces. However, a certain geochemical composition, or geomagnetic anomalies, may remain, among other things.
“Our research is particularly timely given the recent return of the first samples from the Antarctic-Aitken Basin from Chang’e Mission 6 From China. Combining these new samples with our zircon age data could greatly expand our understanding of the history of this major impact basin and the broader impact history of the early solar system.
The research results were published in a scientific journal. Scientific progress.
