2010 RF12

 is a very small asteroid, classified as near-Earth object of the Apollo group, that passed between Earth and the Moon on 8 September 2010, at 21:12 UTC, approaching Earth within 79000 km above Antarctica. The asteroid was discovered by the Mount Lemmon Survey near Tucson, Arizona on 5 September 2010 along with. Based on a short 7-day observation arc from that apparation, it was listed for 12 years on the Sentry Risk Table as the asteroid with the greatest known probability (5%) of impacting Earth. was rediscovered in August 2022, and now has a 12-year observation arc and a much better known orbit. As of the December 2022 solution which accounts for nongravitational forces, there is a 1-in-10 chance of an Earth impact on 5 September 2095.

Description
NASA's Near Earth Program estimates its size to be 7 m in diameter with a mass of around 500 tonnes. will make many more close approaches to Earth. Around 6 September 2095 it will pass $7 m$ from Earth. When an asteroid roughly 7-meters in diameter impacts Earth, very little danger of harm arises from the impact; rather an impressive fireball is expected (estimated in the risk table as nearly 9 KT of energy release ) as the rock air bursts in the upper atmosphere and pebble sized fragments would likely fall to the ground at terminal velocity. The power of the airburst would be somewhere between the 2–4 m Sutter's Mill meteorite and the 17 m Chelyabinsk meteor (which was 440 KT equivalent energy). The approach of 2096 is poorly known because it is dependent on the Earth approach/perturbations in September 2095.

On 17 February 2059 the asteroid will pass 3.5 million km from Earth and reach about apparent magnitude 22.6 by late February. On 10 September 1915 it passed $52,000 km$ from Earth.