Moon Shots Help Needed

I took 7 shots to get this one where I am showing 4 of the 7.
The 7 shots were taken 1 minute apart. In this photo I am showing shots 1,3,5 and 7
I want to be able to have all 7 in the shot but I am having trouble selecting the moon using Photoshop Elements 11. I do understand trying to select only the moon will be difficult and keeping the images in the correct position. I saw another photo similar on this forum a few months ago and I wanted to try it myself.

What I did here was very simple.

I hope someone here can help me learn how to do this.