Duplicate "Random" planet textures

[B-McKinley]

I was just curious if the surface textures for planets/moons are supposed to be truly random. I built a system and when placing moons I would come across the occasional moon that looked really familiar - because it was the same surface features, just colored differently. Should I be seeing "twins" like this, or is this possibly a bug? I can attempt to recreate the effect if needed.

[codefantastic]

The textures are based on a set of height maps that are randomly combined and colored. So it's not unlikely to see familiar looking textures.