65803 Didymos is a 750-m wide near-Earth asteroid belonging to the Apollo group. Discovered in 1996, it has a small moon about 160 m in diameter, named Dimorphos, which is targeted by NASA's Double Asteroid Redirect Test (DART) mission to test planetary defense methods in September 2022.
NOTE: Download the DART addon to view the simulated impact of the spacecraft onto Dimorphos on 2022-Sept-26
The orbit of its moon, Dimorphos, before and after the DART impact, 2022-Sept-26.
How to install add-ons? Find out here.