| 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 | 86.39yr (31,553 d) |
| Aphelion | 3.6451AU |
| 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] | |
4647 Syuji, provisional designation1931 TU1, is a dark backgroundasteroid from the outer regions of theasteroid belt, approximately 14 kilometers (8.7 miles) in diameter. It was discovered on 9 October 1931, by German astronomerKarl Reinmuth at theHeidelberg Observatory in southwest Germany. The likelycarbonaceous asteroid was named for Japanese astronomerShuji Hayakawa.[1]
Syuji is a non-family asteroid from the main belt'sbackground population.[3] It orbits the Sun in theouter 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 aneccentricity of 0.26 and aninclination of 7° with respect to theecliptic.[2] The body'sobservation arc begins at Heidelberg on 17 October 1931, or eight nights after its official discovery observation.[1] orbital read
Syuji has anabsolute magnitude of 12.8.[2] Based on the body's albedo(see below) and its location in the asteroid belt, it is likely acarbonaceous asteroid. As of 2018, no rotationallightcurve ofSyuji has been obtained fromphotometric observations. The body'srotation period,pole and shape remain unknown.[2]
According to the survey carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Syuji measures 13.864 kilometers in diameter and its surface has analbedo of 0.063.[4]
Thisminor planet was named after Japanese astronomerShuji Hayakawa (born 1958; first name also spelled "Syuji" or "Shūji"), an observer ofcomets anddiscoverer of minor planets at the Okutama Observatory (877) inOkutama, west of Tokyo.[1] The official naming was proposed byTakao Kobayashi and the citation was published by theMinor Planet Center on 25 May 1994 (M.P.C. 23540).[5]
