This is an earth-like planet in orbit around Zeta Tucanae. At present the star is not known to have planets, but I'm taking artistic license!
A closer view of this same planet can be seen here: [link]
All the textures were custom painted - from scratch - in Photoshop. No photos, nothing - that was the point of the exercise.
Painting the clouds was a nightmarish process that required numerous test renders to see the effect when lit in 3D, then jump back to Photoshop and tweak it some more. But I wanted to break away from using the cloud map that is very prevalent in a lot of 3D planet art.
Incidentally, the shadows cast by the clouds are actual raytraced shadows, and the red shift at the terminator is a result of some complex 3D shader work. No matter where the "Sun" is, the color shift into the shadow remains accurate.