Hi Fran,

glad to read about your progress.

Using cloud-planes seems be the best approach here. (I once used multiple 2D-planes with cloud-mats for Space Nebula scenes, with some promising results then. Though already many years ago... am really not brycing many landscapes and "outside sphere" scenes, nowadays. ;)  

Quote -
And, Hubert!  I've got a sphere inside a sphere too! ROFL!

Not "ShinySpheres"(tm,C,R,IHA) I assume/hope??! Otherwise, beware of possible addiction! :)
Always be Nice to Bryce and Cheers to Spheres,
Hubert

 

"All that we see or fear, is but a Sphere inside a Sphere."     (E. A. Pryce -- Tuesday afternoon, 1845)