@MikeRPG, World Machine wouldn’t come to mind right away when considering planetary generation. I did notice though in the most recent release (Mt Daniel Build version 3022) that Stephen included a star field example in the Example Files. Not sure which WM version you are using, but that seems really interesting. Of course it doesn’t actually produce any spheres, rather an image of a star field and a few nebulas. Still, I wonder if anything could be done with that as a template in the meantime (until you find your more permanent solution). In any case I thought it was impressive considering WM is mainly for terrain generation.