(85640) 1998 OX4

' (provisional designation ') is a sub-kilometer asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group.

Description
It was discovered on 26 July 1998 by the Spacewatch program and subsequently lost. It was re-discovered by the Near-Earth Asteroid Tracking (NEAT) project on 31 August 2002, as. It was removed from the Sentry Risk Table on 8 August 2002. It has a well determined orbit with an observation arc of more than 10 years. It is included in the Minor Planet Center list of Potentially Hazardous Asteroids (PHAs) as it comes to within 0.05 AU of Earth periodically. It is also a Mars crossing asteroid