As opposed to planetary-sized bodies, asteroid moons are thought to commonly form by this process.

It is famed as one of the first asteroids to be found to have a asteroid moon orbiting it.

It was one of the first asteroid moons to be identified.

This was the first time an asteroid moon had been discovered by a ground-based telescope.

Since Dactyl was found, other sightings have suggested that asteroid moons are common.

Petit-Prince was the first asteroid moon to be discovered with a ground-based telescope.

To be an asteroid moon, an asteroid has to be smaller than the object it goes around.

These images provided the first direct confirmation of an asteroid moon.

Occasionally for asteroid moons, such as the moons of 87 Sylvia.

Since the two asteroid moons appear to orbit (as best we can tell) in the same plane, they would occult each other once every 2.2 days.