Discovered by LINEAR MPC designation 21558 Alisonliu Minor planet category main-belt · Eunomia Orbits Sun Discovery site Experimental Test Site | Discovery date 24 August 1998 Alternative names 1998 QW77 · 1992 CX Discovered 24 August 1998 Asteroid family Eunomia family Asteroid group Asteroid belt | |
Named after Alison W. Lui
(awardee 2006 ISEF) Discoverer Lincoln Near-Earth Asteroid Research People also search for Sun, 2384 Schulhof, 817 Annika | ||
21558 Alisonliu, provisional designation 1998 QW77, is a stony Eunomia asteroid from the middle region of the asteroid belt, approximately 8 kilometers in diameter. It was discovered by the Lincoln Near-Earth Asteroid Research at the U.S. Lincoln Laboratory's Experimental Test Site in Socorro, New Mexico, on 24 August 1998.
The asteroid is a member of the Eunomia family, a large group of S-type asteroids and the most prominent family in the intermediate main-belt. It orbits the Sun at a distance of 2.2–3.1 AU once every 4 years and 4 months (1,597 days). Its orbit has an eccentricity of 0.16 and an inclination of 12° with respect to the ecliptic. The first precovery was taken at the Venezuelan OAN de Llano del Hato in 1992, extending the asteroid's observation arc by 6 years prior to its discovery.
A rotational light-curve of this asteroid was obtained from photometric observations made at the Australian Oakley Southern Sky Observatory (E09) in April 2010. The light-curve gave a well-defined rotation period of 7000486599999999999♠4.866±0.003 hours with a brightness amplitude of 0.12 in magnitude (U=3). According to the survey carried out by the NEOWISE mission of NASA's space-based Wide-field Infrared Survey Explorer, Alisonliu measures 6.7 and 8.8 kilometers in diameter, and its surface has an albedo of 0.229 and 0.245, respectively, while the Collaborative Asteroid Lightcurve Link assumes an albedo of 0.21 and calculates a diameter of 8.4 kilometers, based on an absolute magnitude of 12.7.
The minor planet was named after Alison Liu (b. 1989) who was awarded Intel Best of Category in the 2006 Intel International Science and Engineering Fair (ISEF) for her behavioral and social science team project. In addition, she received the EU Contest for Young Scientists Award. At the time, Liu attended the Manhasset Secondary School in the U.S. state of New York. Naming citation was published on 11 July 2006 (M.P.C. 57276).