The Asteroid is more a very small planetoid ( 15000m/ 28000m / 32000m ).
One third of that planetoid has broken away, and has left a very "edgy" surface, with a couple of large, deep canyons. The areas of that part of the rock are plastered with "spikes" of various size ( from length 100m and 6m diameter to 800m length and 37m diameter), and debris of various size.
A noticeable "landmark" is a large "tongue", which "juts" from the bottom of the rock, like it was unwilling to break apart with the rest of the debris.
The other side of the rock has a couple of craters of various size, most of 'em "weathered" out ( no sharp edges ),
the largest of 'em ( 900m diameter )has debris in it, leftover from the impact of a larger rock.
After thinking about it, i corrected the poly counts for the Asteroid.
I assume 5000 are simply not enough, and the edgy surface will eat a lot of polys, since it is supposed to be detailed ( although the spikes don't require that many polys).
Additionally, ( optional, since not really necessary ) there is a cavern which can be accessed through three small tunnels which have sharp corners, and are only 20-30m in diameter.