The Giant Impact Hypothesis
The giant impact hypothesis is one of many hypothesis that explain the formation of the moon. Arguably it is the best explanation we have and the one everyone goes with.
Long ago in the early days of the solar system there was many objects orbiting the Sun. Many more than the planets. Which also means that there was a ton of collisions. The earth was sitting there with rivers of lava on it along with tons of collisions every second. But there was one special collision. It was Mars-sized object given the unofficial name Theia hit the earth. It was grazing impact causing rocks to go in orbit the earth. With time these rocks -under their own gravity- formed the moon.
Types of carters.
Why does the moon have craters ?
Before i dive into this you have to know one thing. From earth we only see one side of the moon. The other side is hidden from us because of tidal locking. Now there is a difference between the far side and the side we see as seen in the picture below.
But why ? Why is this difference in geography of the moon. Turns out in the old days the moon was much close to the earth that the earth appeared 80 times bigger in the moon’s sky. Not to mention that the earth was hot. So hot that it evaporated the rocks on the near side. These rocks rose up and went to the other side of the moon -the further side- and condensed there making the crust thick so impacts couldn’t get as deep in the far side.
The moon from the inside.
Why does the moon have phases ?
We were told that the moon has phases because it orbits the earth. While that is true it isn’t the only reason. We seem to forget the sun plays a significant role. This video made by Crash Course: