It has been a while since my last pure space wallpaper. I always wanted to do something closer to the origin of planets and solar systems (instead of blowing things up all the time and destroying them). I still have some other ideas in mind so you can expect some follow-up images later.
To the image itself: similar to the formation of Earth and Moon there is debris of stones surrounding the main planet. The stones are accumulating at certain places and finally forming a moon.