[tvoelcker]

Perhaps consider cropping a bit off the top and left hand side.
When we read a piece of paper we usually start at the top left hand corner and end at the bottom right hand corner. Perhaps placing the moon and planet at or closer to these points would improve the composition? Note: this is just me thinking out loud as usual.
I've never attempted shooting the moon so can't be of much assistance with lens choice etc.
However, I do thank you for sharing..