For centuries, humanity has seen the moon as a ball of mysteries. The greatest mystery, perhaps, is how it came to be.
It's a long-held belief that the moon was created when part of the earth was cut off the side and thrown into orbit after a massive object hit the earth. Nature's recent paper revealed that it was not an easy "birth," as opposed to what was previously believed. According to scientists, the moon came into being through a violent space collision.
The Giant-Impact hypothesis that emerged in the 1970s states that the moon was formed when a Mars-sized object called Theia collided with the young Earth. From this low-energy graze that happened 4.5 billion years ago, a small accretion disc was formed, giving birth to the moon.
Geochemists from Harvard and Washington University contend that the birth of the moon is more violent than what the widely known hypothesis proposes. The scientists involved in the research still used the Apollo moon samples from the 1970s, although with more modern measuring tools.
"Everything we know about the early solar system is from our study of meteorites and lunar samples, all those really really old rocks," said Kun Wang, an assistant professor at Washington University. "It has changed our understanding of the early solar system, it's much more violent than we thought."
Simulations of the impact show that the material of the moon would mostly come from Theia, and there's a small chance that Earth and Theia are made from the same material. By analyzing lunar rocks using new technology, scientists found that their chemical make-up is almost similar to earth rocks, except moon rocks have heavy-potassium isotope, which can only be explained if there was an incredibly hot temperature involved. This led scientists to conclude that the birth of the moon involved a violent collision, which resulted in Earth absorbing part of Theia.
This new theory did not escape criticism, though. Munir Humayun, a geologist at Florida State University, said that there's not enough evidence to prove the hypothesis and that the team should have used better samples.
