(24984) Usui = 1998 KQ42
Discovered 1998 May 27 by the Lowell Observatory Near-Earth Object Search at the Anderson Mesa Station. Fumihiko Usui (b. 1974) is a research associate at the University of Tokyo. He played a central role in assembling the data catalog for more than 5000 asteroids measured in the infrared by the Akari satellite.
(The Minor Planet Circulars 88763, 2014 July 12)

Semimajor axis = 2.259 au
Diameter = 2.535 km, albedo = 0.208 (WISE; Mainzer et al. 2011)
(JPL Small-Body Database Browser)