4647 Syuji, provisional designation 1931 TU1, is a dark background asteroid from the outer regions of the asteroid belt, approximately 14 kilometers (8.7 miles) in diameter. It was discovered on 9 October 1931, by German astronomer Karl Reinmuth at the Heidelberg Observatory in southwest Germany. The likely carbonaceous asteroid was named for Japanese astronomer Shuji Hayakawa.[1]
| Discovery [1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 9 October 1931 |
| Designations | |
| (4647) Syuji | |
Named after | Shuji Hayakawa [1] (Japanese astronomer) |
| 1931 TU1 · 1970 PD 1979 FN3 · 1979 GA 1980 RF4 | |
| main-belt [1][2] · (outer) background [3] | |
| Orbital characteristics [2] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 86.39 yr (31,553 d) |
| Aphelion | 3.6451 AU |
| Perihelion | 2.1369 AU |
| 2.8910 AU | |
| Eccentricity | 0.2608 |
| 4.92 yr (1,795 d) | |
| 240.47° | |
| 0° 12m 1.8s / day | |
| Inclination | 6.9377° |
| 180.58° | |
| 128.29° | |
| Physical characteristics | |
| 13.864±0.057 km[4] | |
| 0.063±0.004[4] | |
| 12.8[2] | |
Syuji is a non-family asteroid from the main belt's background population.[3] It orbits the Sun in the outer main-belt at a distance of 2.1–3.6 AU once every 4 years and 11 months (1,795 days; semi-major axis of 2.89 AU). Its orbit has an eccentricity of 0.26 and an inclination of 7° with respect to the ecliptic.[2] The body's observation arc begins at Heidelberg on 17 October 1931, or eight nights after its official discovery observation.[1] orbital read
Syuji has an absolute magnitude of 12.8.[2] Based on the body's albedo (see below) and its location in the asteroid belt, it is likely a carbonaceous asteroid. As of 2018, no rotational lightcurveofSyuji has been obtained from photometric observations. The body's rotation period, pole and shape remain unknown.[2]
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Syuji measures 13.864 kilometers in diameter and its surface has an albedo of 0.063.[4]
This minor planet was named after Japanese astronomer Shuji Hayakawa (born 1958; first name also spelled "Syuji" or "Shūji"), an observer of comets and discoverer of minor planets at the Okutama Observatory (877) in Okutama, west of Tokyo.[1] The official naming was proposed by Takao Kobayashi and the citation was published by the Minor Planet Center on 25 May 1994 (M.P.C. 23540).[5]
