| Discovery[1] | |
|---|---|
| Discovered by | T. Seki |
| Discovery site | Geisei Obs. |
| Discovery date | 23 October 1981 |
| Designations | |
| (2571) Geisei | |
Named after | Geisei(Japanese village)[2] |
| 1981 UC · 1931 TA4 1934 NV · 1944 OD 1961 XG · 1981 WR6 A911 UC | |
| main-belt · Flora[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 85.64 yr (31,280 days) |
| Aphelion | 2.6607AU |
| Perihelion | 1.7953 AU |
| 2.2280 AU | |
| Eccentricity | 0.1942 |
| 3.33yr (1,215 days) | |
| 317.69° | |
| 0° 17m 47.04s / day | |
| Inclination | 2.8722° |
| 66.915° | |
| 284.78° | |
| Physical characteristics | |
| Dimensions | 5.21±0.95 km[4] 5.23±1.07 km[5] 6.582±0.035 km[6][7] 6.81 km(calculated)[3] |
| 7.823±0.005h[8] | |
| 0.24(assumed)[3] 0.2573±0.0688[6] 0.275±0.059[7] 0.34±0.14[4] 0.38±0.24[5] | |
| S[3] | |
| 12.9[5] · 13.0[1][3][6] · 13.32±0.26[9] · 13.38[4] | |
2571 Geisei, provisional designation1981 UC, is a stony Florianasteroid from the inner regions of theasteroid belt, approximately 6 kilometers in diameter. It was discovered by Japanese astronomerTsutomu Seki atGeisei Observatory on 23 October 1981, and named for the Japanese village ofGeisei.[2][10]
Geisei is a member of theFlora family, one of the largest families ofstony asteroids. It orbits the Sun in theinner main-belt at a distance of 1.8–2.7 AU once every 3 years and 4 months (1,215 days). Its orbit has aneccentricity of 0.19 and aninclination of 3° with respect to theecliptic.[1]
In October 1911,Geisei was first identified asA911 UC atHeidelberg Observatory. The asteroid'sobservation arc begins 50 years prior to its discovery, with aprecovery taken atLowell Observatory in 1931.[10]
A rotationallightcurve for this asteroid was obtained from photometric observations made at the Australian Oakley Southern Sky Observatory (E09) in September 2014. The lightcurve gave arotation period of7.823±0.005 hours with a brightness variation of 0.50 inmagnitude (U=3-).[8]
According to the 2015/16NEOWISE mission results of NASA's space-basedWide-field Infrared Survey Explorer,Geisei measures 5.21 and 5.23 kilometers in diameter and its surface has analbedo of 0.34 and 0.38, respectively.[4][5] Preliminary WISE results gave a diameter of 6.582 kilometers and an albedo of 0.275.[6][7]
TheCollaborative Asteroid Lightcurve Link assumes an albedo of 0.24 – derived from8 Flora, the largest member and namesake of the Flora family – and calculates a diameter of 6.81 kilometers using anabsolute magnitude of 13.0.[3]
Thisminor planet is named after the small Japanese village ofGeisei, where the discovering observatory is located. Geisei is situated near the city ofKōchi, after which Tsutomu Seki's first discovery, the asteroid2396 Kochi, is named.[2] The approved naming citation was published by theMinor Planet Center on 6 June 1982 (M.P.C. 6956).[11]
