.png) Lightcurve-based 3D-model ofSaheki | |
| Discovery[1] | |
|---|---|
| Discovered by | T. Seki |
| Discovery site | Geisei Obs. |
| Discovery date | 27 October 1987 |
| Designations | |
| (4606) Saheki | |
Named after | Tsuneo Saheki(astronomer)[2] |
| 1987 UM1 · 1972 GA1 1977 TJ7 · 1977 VF2 1982 FH4 | |
| main-belt · Flora[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 63.81 yr (23,305 days) |
| Aphelion | 2.4805AU |
| Perihelion | 2.0231 AU |
| 2.2518 AU | |
| Eccentricity | 0.1016 |
| 3.38yr (1,234 days) | |
| 202.74° | |
| 0° 17m 30.12s / day | |
| Inclination | 2.6338° |
| 241.26° | |
| 251.92° | |
| Physical characteristics | |
| Dimensions | 6.655±0.069[4] 6.712±0.041 km[5] 7.14 km(calculated)[3] |
| 4.969±0.003h[a] 4.97347±0.00005 h[6] 5.032±0.001 h[7] | |
| 0.24(assumed)[3] 0.3266±0.0245[5] 0.332±0.088[4] | |
| S[3] | |
| 12.7[5] · 13.0[1][3] · 13.35±0.32[8] | |
4606 Saheki, provisional designation1987 UM1, is a stony Floraasteroid from the inner regions of theasteroid belt, approximately 7 kilometers in diameter.
The asteroid was discovered on 27 October 1987, by Japanese astronomerTsutomu Seki atGeisei Observatory, Japan.[9] It was later named after Japanese astronomerTsuneo Saheki.[2]
Saheki 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 2.0–2.5 AU once every 3 years and 5 months (1,234 days). Its orbit has aneccentricity of 0.10 and aninclination of 3° with respect to theecliptic.[1] The firstprecovery was taken atPalomar Observatory in 1953, extending the asteroid'sobservation arc by 34 years prior to its discovery.[9]
In January 2009, a rotationallightcurve ofSaheki was obtained from photometric observations byDavid Higgins at Hunters Hill Observatory, Australia. Lightcurve analysis rendered a well-definedrotation period of4.969 hours with a brightness variation of 0.56 inmagnitude (U=3).[a]
Two months later, in March 2009, a second lightcurve was obtained at the Via Capote Observatory (G69), California. It gave a period of5.032 and an amplitude of 0.68 in magnitude (U=3-).[7]
In 2013, an international study modeled a lightcurve with a concurring period of 4.97347 hours and found aspin axis of (44.0°, 59.0°) and (222.0°, 68.0°) inecliptic coordinates (λ, β), respectively (Q=2).[6]
According to the survey carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Saheki has a highalbedo of 0.33 and a diameter of 6.7 kilometers,[4][5] while theCollaborative Asteroid Lightcurve Link calculates a diameter of 7.1 kilometers, based on an assumed albedo of 0.24, derived from8 Flora, the Flora family's namesake and largest member.[3]
Thisminor planet was named after Japanese astronomer and president of theToa Astronomical Society, Tsuneo Saheki (1916–1996). Over half a century, Saheki as gathered large inventory of observational data of the planet Mars.[2] The Martian craterSaheki is also named in his honour. The official naming citation was published by theMinor Planet Center on 28 May 1991 (M.P.C. 18308).[10]
