(517103) 2013 EM20 (also designated 2008 AO112) is an Apollo near-Earth asteroid and potentially hazardous object.
[2] It was discovered on 12 January 2008 by the Mount Lemmon Survey at an apparent magnitude of 21 using a 1.5-meter (59 in) reflecting telescope.
[1] The asteroid was quickly lost and had an estimated diameter of 310 meters (1,020 ft).
[3] The virtual impactor had not been eliminated from the Sentry Risk Table by the day of the potential impact.
[4] Precovery images from 7 April 1997 at Kitt Peak National Observatory were located.