P/2016 G1 (PanSTARRS) was a main-belt asteroid that was destroyed by an impact event on 6 March 2016. It was discovered by Robert Weryk and Richard Wainscoat of the Pan-STARRS 1 survey at Haleakala Observatory. The object was initially thought to be an Encke-type comet because of its diffuse appearance,[1] so it received the periodic comet designation P/2016 G1. After further analysis, what had initially appeared to be a comet's halo turned out to be rubble from a collision. By November 2019, analysis suggested the collision had occurred on 6 March 2016, and the asteroid was struck by a smaller object that may have massed only 1kg (02lb), and was traveling at 11000mph. P/2016 G1's diameter was between 200m (700feet) and 400m (1,300feet). The asteroid had completely disintegrated by 2017.
Astronomers were able to use the asteroid's rubble to determine the date of the collision, since the dispersion of dust was inversely proportional to its size.