Asteroid created using maya's 3dtexture procedurals.
Essentially a simple piece of geometry, which is left still easily editable, being subdivided and displaced by a procedural textures.
To animate just grab asteroid and animate. No need to parent the 3dtexture to the asteroid because it is set to 'local'.
If scaling is needed I recommend baking displacement maps or freezing the displacement to the mesh first. Otherwise you will need to scale both the 3dtexture and geometry. Then you will need to adjust the alphagain of the procedural to make the displacement stick out appropriately far.