| Discovery[1] | |
|---|---|
| Discovered by | C. S. Shoemaker E. M. Shoemaker D. H. Levy |
| Discovery site | Palomar Obs. |
| Discovery date | 10 February 1991 |
| Designations | |
| (6398) Timhunter | |
Named after | Tim Hunter (amateur astronomer)[2] |
| 1991 CD1 · 1955 DB 1988 PG | |
| main-belt · Phocaea[3][4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 62.19 yr (22,716 days) |
| Aphelion | 2.8684AU |
| Perihelion | 1.8179 AU |
| 2.3431 AU | |
| Eccentricity | 0.2242 |
| 3.59yr (1,310 days) | |
| 119.46° | |
| 0° 16m 29.28s / day | |
| Inclination | 23.856° |
| 128.98° | |
| 67.697° | |
| Physical characteristics | |
| Dimensions | 5.20±1.11 km[5] 5.528±0.112 km[6][7] 5.79 km(calculated)[3] |
| 7.1074±0.0007h[8] 14.55±0.01 h[a] | |
| 0.23(assumed)[3] 0.27±0.12[5] 0.333±0.049[6][7] | |
| S[3] | |
| 13.1[6] · 13.4[1][3] · 13.59±0.81[9] · 13.63[5] | |
6398 Timhunter, provisional designation1991 CD1, is a stony Phocaeaasteroid from the inner regions of theasteroid belt, approximately 5.5 kilometers in diameter. It was discovered on 10 February 1991, by American astronomer coupleCarolyn andEugene Shoemaker, in collaboration with Canadian astronomerDavid H. Levy atPalomar Observatory in California, United States.[10] It was named for American amateur astronomerTim Hunter.[2]
The stonyS-type asteroid is a member of thePhocaea family (701),[4] a relatively small group of asteroids with similar orbital characteristics.Timhunter orbits the Sun in theinner main-belt at a distance of 1.8–2.9 AU once every 3 years and 7 months (1,310 days). Its orbit has aneccentricity of 0.22 and aninclination of 24° with respect to theecliptic.[1] It was first identified as1955 DB atGoethe Link Observatory in 1955, extending the body'sobservation arc by 36 years prior to its official discovery observation at Palomar.[10]
In March 2009, a rotationallightcurve ofTimhunter was obtained from photometric observations by astronomerPetr Pravec at theOndřejov Observatory in the Czech Republic. Lightcurve analysis gave a well-definedrotation period of 14.55 hours with a brightness variation of 0.29magnitude (U=3).[a] One month later, another lightcurve was obtained by French amateur astronomersDavid Romeuf, Maurice Audejean andRené Roy, which gave an alternative period solution of 7.1074 hours with an amplitude of 0.32 magnitude (U=2-).[8]
According to the survey carried out by NASA'sWide-field Infrared Survey Explorer with its subsequentNEOWISE mission,Timhunter measures 5.20 and 5.528 kilometers in diameter, and its surface has analbedo of 0.333 and 0.27. respectively.[5][6][7] TheCollaborative Asteroid Lightcurve Link assumes an albedo of 0.23 – derived from25 Phocaea, the Phocaea family's namesake – and calculates a diameter of 5.79 kilometers, based on anabsolute magnitude of 13.4.[3]
Thisminor planet was named afterTim Hunter, an American radiologist and amateur astronomer. Together withDavid Crawford he co-founded the non-profitInternational Dark-Sky Association with the aim to preserve and protect Earth's night sky from light pollution.[2] The approved naming citation was published by theMinor Planet Center on 1 June 1996 (M.P.C. 27330).[11]
