2014 RC

With an absolute magnitude of 26.8, the asteroid is about 11–25 meters (36–82 ft) in diameter depending on the albedo. Observations by the NASA Infrared Telescope Facility conclude the asteroid is a fairly bright Sq-class asteroid which have an average albedo of around 0.24, and would give the asteroid a spherical equivalent diameter of 12 meters (39 ft). Measurements by multiple telescopes indicate that the asteroid rotates in 15.8 seconds making it one of the fastest rotating asteroids so far discovered. Using the 15.8 second rotation period, more accurate radar observations by Goldstone shows the asteroid has a largest axis of at least 22 meters (72 ft). Due to the asteroid's fast rotation, it is a monolith and not a rubble pile.

On 8 September 2115 the asteroid will pass about 0.0053 AU (790,000 km; 490,000 mi) from the Moon. On 5 September 1973, the asteroid passed between 0.01052 AU (1,574,000 km; 978,000 mi) and 0.01207 AU (1,806,000 km; 1,122,000 mi) from Earth. 2014 RC was removed from the JPL Sentry Risk Table on 5 September 2014 and there are no known possible impact dates in the next 100 years.

2014 approach

It made a close approach to Earth of 0.000267 AU (39,900 km; 24,800 mi) (0.1 LD) around 18:02 UTC on 7 September 2014. The asteroid briefly brightened to about apparent magnitude 11.5, but it was still not visible to the naked eye or common binoculars. At the peak brightness the asteroid had a declination of –47, and was most easily visible over New Zealand. During 2014, asteroids 2014 AA and 2014 LY21 have come closer to Earth.

The Managua explosion on 6 September 2014 may or may not have been created by a bolide that was missed by millions of people, but either way it was not caused by the close approach of 2014 RC.