You know those lines in the sky remind my of some of the early concept art for the motion picture Tron for some reason: I can't see spikes in the image, but I maybe looking in the wrong place: on the whole this is a great beginning here.
Edit:
On further examination of the image, are you talking about the vary small spikes on the planets rim? Which can only be seen if the Image is viewed full size.
Regards to you.
Cyber-Angel