After studying some reference photos, I played about with the planetary ring texture a little more in Blender.
Also, the sun is now shining from the lower left and has a bit of a red tinge to suggest a sunset.
I then scaled the whole model up by roughly a factor of ten because I will then locate a camera on the planet surface and take a render with the rings coming down from the sky to the horizon.
Hopefully I can use the render as a background for a digital painting of the Dark Temple Of Mymosule.
