Sorry if I sound blunt, but why didn't you just read the FAQ? If you did, you would've known that the textures of solar system planets are blurry since they aren 't procedural. Go to any procedurally generated world and the detail will be much higher(if your LOD is 0 or higher, the detail is fantastic in my experience) .
Yes, you are right. I read it right after this post and I felt like a total idiot. I am sorry.
Please lock this thread. I am currently downloading some add-ons for our solar system.