Earth's Moon Might Have Been Formed by Tiny Moons All Crashing Together

How did the moon come into fruition? There are many theories. The most recent one observes it may have been the product of many moonlets coming together.

According to a report from Space, the study published in Nature Geoscience revealed that the theory revolves around the event of roughly 20 objects colliding with the Earth. These objects range from the size of the moon to as big as Mars and their collision with the planet sent debris into orbit, which created disks similar to Saturn's rings. Through hundreds of years, the disks became moonlets that drifted away from the Earth and eventually colescing into a single large moon that exists at present.

"The multiple-impact scenario is a more natural way of explaining the formation of the moon," Raluca Rufu, lead author of the study and a researcher at the Weizmann Institute of Science in Israel, said in the Space report. "In the early stages of the solar system, impacts were very abundant; therefore, it is more natural that several common impactors formed the moon, rather than one special one."

According to a report from Phys Org, this theory would solve an inconsistency in the prevailing hypothesis that the moon was created by one massive impact between the Earth and a Mars-sized object. Here, the moon would have just a fifth of the Earth's composition and the rest of it would be from the other heavenly body. The reality is, the composition of Earth and the moon is incredibly similar.

Gareth Collins from the Imperial College London wrote that the new research "revived the hitherto largely discarded scenario that a series of smaller and more common impacts, rather than a single giant punch, formed the Moon. Building the Moon in this way takes many millions of years, implying that the Moon's formation overlapped with a considerable portion of Earth's growth."