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It went along when the moon broke off from the Earth!

 4 years ago 

They used to be attached to each other? I have not yet heard of that.

I understand the prevailing theory to be that the moon is essentially a big chunk of the Earth. That's likely the reason that the same part of the moon always faces the Earth.

Exciting, huh?

 4 years ago 

Is it the one referred to as the giant-impact theory? I just read on it.

That makes sense because the idea is that something large hit the mass that was the precursor to earth as it is now. A chunk of the planetary mass broke off, and ended up staying gravitationally locked in orbit! 👍