Moon formed solely from Earth's materials, no Theia

A new study has changed the understanding of how the Moon formed. Researchers suggest that the Moon is entirely made from material ejected from Earth, without any contributions from Theia. Theia is a theoretical planet, roughly the size of Mars, which was thought to have collided with Earth early in its history. Scientists conducted a study on 14 lunar rock samples and compared them to similar Earth minerals. They specifically looked at levels of oxygen-17, a rare isotope. The results showed that the levels were nearly identical in both the Moon and Earth samples. This led researchers to conclude that the Moon's material originated solely from Earth. The study proposes that the debris from the collision between Earth and Theia formed the Moon, but there were no remnants of Theia in its structure. Andreas Pack, a scientist from Göttingen University, explained that if Theia lost its rocky outer layer in earlier collisions, it could have impacted Earth as a metallic core, making Theia part of Earth's core today. The research also examined the origins of water on Earth. While Theia was once thought to have brought water to Earth, the study suggests that asteroids might have delivered water later, after the Moon formed. The evidence points to a specific group of meteorites, called enstatite chondrites, as potential sources of water, as they contain similar oxygen-17 levels. Overall, Theia continues to intrigue researchers, who believe it may have played a role in shaping Earth's continents and volcanic activity.