Where did the moon come from?

There's something wrong with this story. It goes, once upon a time in a cozy orbit around a yellow dwarf star, — a young planet was just starting to cool when out of nowhere it was struck by Theia, a planet about half its diameter. A spray of molten rock formed a ring of debris that eventually came together to form a moon. Our moon. This is the giant impact hypothesis. I think it's a very attractive story because it's dramatic and it's easy to explain, it's easy to visualize. But when you stop to ask, "Hey, how do they know that? " which is what we do on this channel, you discover that this simple story has one fatal flaw, one mystery that no one has been able to crack. A lot of people might be content with the simple story, but this video is for people who are curious about how science really works, how we can even begin to piece together what happened over 4 billion years ago, how we really ended up with our big, weird, perfect moon.