Discovered by T. Kojima MPC designation 9321 Alexkonopliv Discovered 5 January 1989 Orbits Sun | Discovery date 5 January 1989 Minor planet category main-belt · (outer) Absolute magnitude 12.9 Asteroid group Asteroid belt | |
Named after Alex Konopliv(astronomer) Alternative names 1989 AK · 1977 VZ11977 XD · 1984 EK People also search for Sun, 4576 Yanotoyohiko | ||
9321 Alexkonopliv, provisional designation 1989 AK, is a carbonaceous asteroid from the outer region of the asteroid belt, approximately 11 kilometers in diameter. It was discovered on 5 January 1989, by Japanese astronomer Takuo Kojima at the YGCO Chiyoda Station, Japan.
The dark C-type asteroid orbits the Sun at a distance of 2.3–3.9 AU once every 5 years and 6 months (2,002 days). Its orbit has an eccentricity of 0.26 and an inclination of 4° with respect to the ecliptic. The first precovery was taken at Purple Mountain Observatory in 1977, extending the asteroid's observation arc by 12 years prior to its discovery.
A rotational light-curve was obtained from photometric observation made at the Palomar Transient Factory, California, in December 2010. The light-curve gave a rotation period of 7000342680000000000♠3.4268±0.0010 hours with a brightness amplitude of 0.19 in magnitude (U=2). According to the survey carried out by NASA's space-based Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, the asteroid measures 10.3 kilometers in diameter and its surface has an albedo of 0.116, while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a diameter of 11.5 kilometers, based on an absolute magnitude of 13.43.
It is named after JPL-scientist Alex Konopliv (b. 1960), an internationally recognized authority on the measurement of the gravitational field of Solar System bodies tracked by satellites in Earth's orbit. Various Mars missions used his gravity field determinations for the Red Planet. Naming citation was published on 5 October 1998 (M.P.C. 32610).