The early Solar system was a particularly violent place where lots of sizeable masses collided into each other until they formed the Sun and all the planets.
During this period our Moon was formed. We know that the Earth doesn’t have the gravity to capture a planet the size of the Moon so there had to be another explanation. The giant impact hypothesis states that the Moon was formed out of the debris left over from an indirect collision between the Earth and an astronomical body the size of Mars, approximately 4.5 Gya in the Hadean eon. The theorized planet is named Theia.
In Greek mythology, Theia is the Titaness of sight and enlightenment one of the old gods before the Olympians. She was also the mother of Selene, goddess of the Moon. However, evidence of greek gods isn’t the evidence that scientists found.
Using lunar rocks brought back by Apollo astronauts scientists have found traces of the “planet” called Theia. This has led them to conclude that the Moon was in fact created by the collision between the first Earth and the one we live on today. Well, almost.
Earlier simulations had shown the Moon to have originated entirely from the Earth whereas computer simulations had shown that the Moon ought to have been mostly derived from Theia. It turns out that neither one is exactly right. So scientists will have to work on new theories of the origin of the Moon, but the evidence has tilted decidedly in favor of an impact forming the Moon. They just have to figure out exactly how it happened.
– Ex astris, scientia –
I am and avid amateur astronomer and intellectual property attorney in Pasadena, California and I am a Rising Star as rated by Super Lawyers Magazine. As a former Chief Petty Officer in the U.S. Navy, I am a proud member of the Armed Service Committee of the Los Angeles County Bar Association working to aid all active duty and veterans in our communities. Connect with me on Google +