(137108) 1999 AN10 is a near-Earth asteroid (NEA) of the Apollo group. It was discovered by LINEAR on January 13, 1999.
On August 7, 2027, this NEA will pass within 0.0026 AU (390,000 km; 240,000 mi) (~1 lunar distance) of the Earth. During the close approach, the asteroid should peak at about apparent magnitude 7.3, and will be visible in binoculars.
1999 AN10 has a well determined orbit with an observation arc of 58 years. It was found by Andreas Doppler and Arno Gnädig in precovery images from 1955. When 1999 AN10 only had an observation arc of 123 days, there was a 1 in 10 million chance that it could return on an impact trajectory in 2039.
On August 7, 1946, the asteroid passed 0.00625 AU (935,000 km; 581,000 mi) from Earth and then 0.00404 AU (604,000 km; 376,000 mi) from the Moon.