| Discovery[1] | |
|---|---|
| Discovered by | E. F. Helin |
| Discovery site | Palomar Obs. |
| Discovery date | 22 August 1987 |
| Designations | |
| (4897) Tomhamilton | |
Named after | Thomas William Hamilton (American writer)[2] |
| 1987 QD6 · 1971 QV1 1971 SB1 · 1990 BN1 | |
| main-belt · (outer) | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 66.81 yr (24,402 days) |
| Aphelion | 3.4356AU |
| Perihelion | 2.6792 AU |
| 3.0574 AU | |
| Eccentricity | 0.1237 |
| 5.35yr (1,953 days) | |
| 262.29° | |
| 0° 11m 3.84s / day | |
| Inclination | 11.067° |
| 188.47° | |
| 107.13° | |
| Physical characteristics | |
| Dimensions | 13.711±0.369 km[3] |
| 0.215±0.065[3] | |
| 12.0[1] | |
4897 Tomhamilton, provisional designation1987 QD6, is a stonyasteroid from the outer region of theasteroid belt, approximately 14 kilometers in diameter. It was discovered on 22 August 1987, by American astronomerEleanor Helin atPalomar Observatory, California. It was later named after American writer Thomas William Hamilton, an author of astronomy books and participant in theApollo program.[2]
Tomhamilton orbits the Sun in theouter main-belt at a distance of 2.7–3.4 AU once every 5 years and 4 months (1,953 days). Its orbit has aneccentricity of 0.12 and aninclination of 11° with respect to theecliptic.[1]
In August 1950, a firstprecovery was taken at Palomar, extending the asteroid'sobservation arc by 37 years prior to its official discovery observation.[2] It had also been previously identified as1971 QV1 and1971 SB1 atCrimea–Nauchnij.
On 11 January 2011, it was atopposition (coinciding with Hamilton's 72nd birthday) at a distance of 2.476 AU. Given the moderately elliptical orbit, this asteroid can reach anapparent magnitude from Earth of between 15.3 and 19.5.[4]
Thisminor planet was named after Thomas William Hamilton, an American (bornSan Francisco, January 11, 1939)[citation needed] who had worked on theApollo program, determining fuel requirements andradar accuracy requirements forlunar orbit rendezvous. He later worked as an astronomy educator andplanetarium director, and as an author on astronomical topics, as well as of time travel andscience fiction novels. Hamilton and Helin were acquainted, as he had interviewed her at an astronomical conference for a cable television show he was producing at the time. The officialnaming citation was published by theMinor Planet Center on 4 October 2009 (M.P.C. 67215).[5]
According to the survey carried out by NASA'sWide-field Infrared Survey Explorer with its subsequentNEOWISE mission,Tomhamilton measures 13.7 kilometers in diameter and its surface has analbedo of 0.215, which indicates that it of astony rather than of acarbonaceous composition.[3]
As of 2017, no rotationallightcurve ofTomhamilton has been obtained from photometric observations. Itrotation period, poles and shape remain unknown.[1][6]
