Scientists are not certain of how the moon first came to be. The general consensus right now is that the moon was formed due to a giant cosmic collision, but for now, that's just a broad theory, and the exact type of impact is still heavily debated.
Did the alleged collision manage to vaporize what was Earth then, or was it so small that it barely damaged the planet? This is something scientists can't agree on, and something everyone who is interested in space science would love to find out.
But we may very well find out what happened thanks to a new study published in the journal Nature, which suggests the moon was formed due to a massive impact with the Earth and another huge object, in what may be deemed a three-way collision.
Kun Wang, a geochemist from Washington University in St. Louis, and Stein Jacobsen, a professor of geochemistry at Harvard University, came to this conclusion by studying rock samples brought back to Earth from the moon during the Apollo mission. The samples in question contained isotopes of potassium, and the differences in isotopic compositions between lunar rocks and Earth rocks were measured and compared.
The researchers conclude that the potassium isotopes found on Earth are slightly different from the ones found on the moon.
The moon rocks are host to a heavier isotope of potassium when compared to what is on Earth. This suggests that Earth's mantle, along with the object that allegedly slammed into Earth, may have vaporized after a violent collision and eventually mixed. This might have allowed the moon to condense in the hot atmosphere that was created by the impact.
"Our results provide the first hard evidence that the impact really did (largely) vaporize Earth," said Wang.
There could also be a chance that the space object that was also involved in the alleged collision might have had the same isotopic signature as Earth's. However, researchers believe this is an unlikely scenario.
Some researchers who are seeking to understand more about the moon believe it was formed due to a low-energy impact, but this new study completely undermines those claims.
Scientists are now making moves to dig into the details and decipher what happened. It will take time before we hear anything again on the subject. We hope that by then, things will be more clear, and researchers will also come together on a single conclusion.
Photo: Luigi Mengato | Flickr
