Move the moon?

All of this Earth moving talk had me thinking back to High School, where we once talked about how the moon might have formed. Since it has been a few decades (centuries?) since I was in High School, I decided to take a gander at the current thinking. I found several sites – most are just the same old theory, which is quite good.

At the time Earth formed 4.5 billion years ago, other smaller planetary bodies were also growing. One of these hit earth late in Earth’s growth process, blowing out rocky debris. A fraction of that debris went into orbit around the Earth and aggregated into the moon.

This theory (here or here) is pretty well though out. In 2001, there were some computer simulations done by the Southwest Research Institute that showed this process working. They have posted video, and pictures here. has a good article on this as well.

Interesting stuff.