dust and rubble: Surface of near-Earth asteroid 25143 Itokawa, photographed by Hayabusa, 9th November 2005.
Itokawa was the first asteroid of the “rubble pile” type to be studied. Unlike solid “monolithic” asteroids (4 Vesta, 10 Hygiea), rubble pile asteroids appear to be collections of rocks and dust held together by mutual gravity. In the poetic words of Wikipedia, Itokawa is “almost certainly a coalescence of shattered fragments”.
Image credit: JAXA/NASA.