Asteroids with satellites: Analysis of observational data

The volume of observational information on asteroids and trans-Neptunians with satellites has significantly increased in recent years. In this paper we study the dependence of asteroid duplicity on the main physical parameters of the primary: the size and rotation rate. The proportion of binary asteroids is shown to grow rapidly with the rotation rate of the primary. The pattern of dependence between asteroid duplicity and size is more complex, with peaks in the area of small (<10 km) and large (>100 km) bodies. Noteworthy is the small number of binaries among typical-sized asteroids (10–150 km). All the orbits of asteroidal satellites whose rotation direction is known are shown to be prograde and have small eccentricities and inclinations.