Didymos asteroid system

Asteroid 65803 Didymos (1996 GT), is an Apollo-type rocky (S-type) near-Earth object (NEO) with a perihelion (minimum distance to the Sun) that is just below the aphelion radius (maximum distance to the Sun) of Earth orbit. Didymos is a binary asteroid; the primary body (seen right) has a diameter of around 780 m and a rotation period of 2.26 hours, whereas the Didymoon secondary body has a diameter of around 160 m and rotates around the primary at a distance of around 1.2 km from the primary surface in around 12 hours.