| Discovery[1] | |
|---|---|
| Discovered by | Y. Kushida O. Muramatsu |
| Discovery site | Yatsugatake South Base Obs. |
| Discovery date | 23 November 1989 |
| Designations | |
| (9844) Otani | |
Named after | Toyokazu Otani (astronomy lecturer)[2] |
| 1989 WF1 · 1980 VF1 1996 HA26 | |
| main-belt · Eunomia[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 67.44 yr (24,634 days) |
| Aphelion | 3.2894AU |
| Perihelion | 2.1105 AU |
| 2.7000 AU | |
| Eccentricity | 0.2183 |
| 4.44yr (1,620 days) | |
| 102.78° | |
| 0° 13m 19.92s / day | |
| Inclination | 12.932° |
| 60.733° | |
| 353.14° | |
| Physical characteristics | |
| Dimensions | 3.84 km(calculated)[3] |
| 10.0730±0.0053h[4] | |
| 0.21(assumed)[3] | |
| S[3] | |
| 13.87±0.47[5] · 13.9[1] · 13.939±0.004(R)[4] · 14.39[3] | |
9844 Otani, provisional designation1989 WF1, is a stony Eunomianasteroid from the middle region of theasteroid belt, approximately 4 kilometers in diameter. It was discovered on 23 November 1989, by Japanese astronomersYoshio Kushida andOsamu Muramatsu at theYatsugatake South Base Observatory, Hokuto, near the Greater Tokyo Area, Japan.[6] It was named for Japanese astronomer Toyokazu Otani.[2]
Otani is a member of theEunomia family, a large group ofS-type asteroids and the most prominent family in the intermediate main-belt. It orbits the Sun in thecentral main-belt at a distance of 2.1–3.3 AU once every 4 years and 5 months (1,620 days). Its orbit has aneccentricity of 0.22 and aninclination of 13° with respect to theecliptic.[1] The first used observation was aprecovery taken atPalomar Mountain in 1949, extending the body'sobservation arc by 40 years prior to its official discovery observation.[6]
A rotationallightcurve ofOtani was obtained from photometric observations at thePalomar Transient Factory in February 2013. It gave arotation period of10.073±0.0053 hours with a brightness variation of 0.18 inmagnitude (U=2).[4]
TheCollaborative Asteroid Lightcurve Link assumes analbedo 0.21 – derived from15 Eunomia, the family's largest member and namesake – and calculates a diameter of 3.84 kilometers with anabsolute magnitude of 14.39.[3]
Thisminor planet was named in honor of Toyokazu Otani (born 1928), a renowned observer of minor planets, lecturer at the Gotoh Planetarium, and long-time employee at the Astronomical Museum in Tokyo (1956–1988).[2] The official naming citation was published by theMinor Planet Center on 2 April 1999 (M.P.C. 34355).[7]
