I've been impressed with your space-themed work, especially your planets with translucent rings. This one looks to be an object-populated disc (I've tried that with mediocre results), rather than the solid see-through like those of Saturn. I have yet to recreate something like that. The sky near the horizon looks grainy; could be render settings. And the stars are there all right, but check out Night Full Moon Example Project (Stars Included) by WAS in this forum, File Sharing / General. They are bright enough to be seen through a default Atmosphere setting.