I have a few questions about what we think really happened.
Apparently, there are 3 main types of asteroid distinguished by composition. Carbonaceous, silicate and metallic types. These types are largely distributed in distinct bands in the asteroid belt. Do we know why that happened?
Is it possible for a small asteroid to accrete into a rock? Doesn't it take a lot of pressure and/or temperature to form rock which would only come after a pretty large size has been reached? Does this mean that all of the small hard rocky asteroids are a result of collisions between much larger bodies?