Science 2017: New Evidence Found About The Moon's FormationBy Emily Marks, UniversityHerald Reporter
A new study on the Earth's moon has found that the satellite may have been a product of small moonlets that merged. This is contrary to previous beliefs that it was a result of a single great collision.
Space.com reported that the moon may have been a result of multiple impacts from objects colliding with Earth. The objects are massive, some as big as Mars, and may have left several planetary debris orbiting our planet.
This concept has directly contradicted a theory that suggested how one giant impact resulted to the formation of the moon. The new hypothesis claims that an estimated 20 objects, with the same size as the moon or Mars, struck the Earth and flung debris from the planet into orbit.
With the debris, it formed disks around our home planet which looked similar to Saturn's rings. Over time, it is believed that debris in several disks merged to become moonlets which eventually coalesced to one big moon.
According to Cosmos Magazine, the prevalent Giant Impact hypothesis, which has become a widely accepted origin story of the moon, says that the Earth was struck by a massive planetoid named Theia.
This resulted to huge amounts of debris into a disc around Earth. However, this did not account for the fact that our home planet and its satellite have the same chemical composition. If the Giant Impact hypothesis was true, majority of the material on the moon should have come from Theia.
Raluca Rufu, a researcher at the Weizmann Institute of Science in Israel and lead author of the study, described the multiple-impact theory as a "more natural way of explaining" the moon's formation. She explained that impacts were common in the early phases of the solar system. This would make it natural to have multiple common sources that formed the moon rather than just one giant explosion.