Discovery date 23 November 1989 Minor planet category main-belt · Eunomia Orbits Sun Discovery site Yatsugatake-Kobuchizawa | MPC designation 9844 Otani Discovered 23 November 1989 Asteroid family Eunomia family Asteroid group Asteroid belt | |
Discovered by Y. Kushida
O. Muramatsu Named after Toyokazu Otani
(astronomy lecturer) Alternative names 1989 WF1 · 1980 VF1
1996 HA26 Discoverers Yoshio Kushida, Osamu Muramatsu Similar Sun, 144P/Kushida, 390 Alma, 85 Io, 812 Adele | ||
9844 Otani, provisional designation 1989 WF1, is a stony Eunomian asteroid from the middle region of the asteroid belt, approximately 4 kilometers in diameter. It was discovered on 23 November 1989, by Japanese astronomers Yoshio Kushida and Osamu Muramatsu at the Yatsugatake South Base Observatory, Hokuto, near the Greater Tokyo Area, Japan.
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 2.1–3.3 AU once every 4 years and 5 months (1,620 days). Its orbit has an eccentricity of 0.22 and an inclination of 13° with respect to the ecliptic. The first used observation was a precovery taken at Palomar Mountain in 1949, which extended the asteroid's observation arc by 40 years prior to its official discovery observation.
A rotational light-curve for this asteroid was obtained from photometric observations at the Palomar Transient Factory in February 2013. It gave a rotation period of 7001100730000000000♠10.073±0.0053 hours with a brightness variation of 0.18 in magnitude (U=2). The Collaborative Asteroid Lightcurve Link assumes an albedo 0.21 – derived from 15 Eunomia, the family's largest member and namesake – and calculates a diameter of 3.84 kilometers, based on an absolute magnitude of 14.39.
The minor planet was named in honor of Toyokazu Otani (b. 1928), a renowned observer of minor planets, lecturer at the Gotoh Planetarium, and long-time employee at the Astronomical Museum in Tokyo (1956–1988). Naming citation was published on 2 April 1999 (M.P.C. 34355).