The Moon’s surface resembles an archive of space bombardment: a multitude of craters, from small pits to giant basins, hold traces of a turbulent past. These “scars” were mostly formed 4 billion years ago, when the solar system was going through an era of late formation, during which the planets and satellites were actively “bombarded” by asteroids and planetesimals. Unlike Earth, where erosion and tectonics erase traces of history, the Moon, devoid of atmosphere, preserves it in perfect integrity. This unique “library” helps scientists reconstruct the evolution of our planetary system.
But how does material from the Moon end up on Earth? During asteroid impacts, parts of the lunar soil acquire cosmic velocities and travel towards our planet. Researchers led by Jose Daniel Castro-Cisneros used advanced computer models to trace this amazing process. Their work, published recently, breaks new ground in understanding the interaction between the Earth and its moon.
Bombing simulations
The team applied the REBOUND software package to track the paths of lunar debris over 100,000 years. Unlike previous studies, the modeling took into account the simultaneous motion of the Earth and Moon, as well as realistic emission rates. It turns out that 22.6% of lunar material reaches Earth, and half of that in just the first 10,000 years.
Interestingly, the chances of a fall depend on the location of the launch: debris from the far side of the Moon is more likely to reach us than that launched from the visible side. They fall mostly near the equator – at the poles they are 24% less. The collision speed is 11-13 km/s, and activity peaks at 6 am and 6 pm.
Key to the mysterious objects
The findings explain the origin of mysterious objects around Earth, such as the asteroid Kamo’oalewa. This body, up to 100 meters in diameter, is probably a piece of debris from the Moon that fell into Earth’s orbit. Studying such “space travelers” will help reconstruct the chronology of ancient collisions and understand how they influenced the development of life on our planet.
“This work is a bridge between the geology of the Moon and Earth,” the authors note, “Not only do we see how material migrates between the two, but we also gain tools to decipher their shared history. ”
The study shows: nearly a quarter of lunar emissions end up on Earth, forming an imperceptible but weighty link between the two worlds. The data could also be key to studying the early stages of the solar system, when collisions were the driving force behind its evolution.
Thus, each lunar crater is not just a trace of the past, but a potential “message” to Earth.
Earlier we reported on how long is it to fly to the Moon in a spacecraft?
According to universetoday.com
