|Discovered by||E. F. Helin|
|Discovery site||Palomar Obs.|
|Discovery date||22 August 1987|
|MPC designation||(4897) Tomhamilton|
|1987 QD6 · 1971 QV1|
1971 SB1 · 1990 BN1
|main-belt · (outer)|
|Orbital characteristics |
|Epoch 4 September 2017 (JD 2458000.5)|
|Uncertainty parameter 0|
|Observation arc||66.81 yr (24,402 days)|
|5.35 yr (1,953 days)|
|0° 11m 3.84s / day|
4897 Tomhamilton, provisional designation 1987 QD6, is a stony asteroid from the outer region of the asteroid belt, approximately 14 kilometers in diameter. It was discovered on 22 August 1987, by American astronomer Eleanor Helin at Palomar Observatory, California. It was later named after American Thomas Hamilton, author of astronomy books and participant in the Apollo program.
Classification and orbit
Tomhamilton orbits the Sun in the outer main-belt at a distance of 2.7–3.4 AU once every 5 years and 4 months (1,953 days). Its orbit has an eccentricity of 0.12 and an inclination of 11° with respect to the ecliptic.
In August 1950, a first precovery was taken at Palomar, extending the asteroid's observation arc by 37 years prior to its official discovery observation. It had also been previously identified as 1971 QV1 and 1971 SB1 at Crimea–Nauchnij.
On 11 January 2011, it was at opposition (coinciding with Hamilton's 72nd birthday) at a distance of 2.476 AU. Given the moderately elliptical orbit, this asteroid can on rare occasions reach an apparent magnitude from Earth of about 10.9.
Diameter and albedo
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Tomhamilton measures 13.7 kilometers in diameter and its surface has an albedo of 0.215, which indicates that it of a stony rather than of a carbonaceous composition.
This minor planet was named after Thomas William Hamilton, an American (born San Francisco, 1939) who was a child actor (he played "Barnaby" in Barnaby and Mr. O'Malley and was on the early television show Mr. I-Magination). As an adult he worked on the Apollo program, determining fuel requirements and radar accuracy requirements for lunar orbit rendezvous. He later worked as an astronomy educator and planetarium director, and is the author of time travel and science fiction novels, and also wrote five books on astronomical topics. 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 approved naming citation was published by the Minor Planet Center on 4 October 2009 (M.P.C. 67215).
Books by Hamilton
- Books on astronomical topics:
- Other books:
- Time for Patriots, a time travel adventure novel (978-1-60693-224-7)
- The Mountain of Long Eyes, an anthology of 27 stories of fantasy, science fiction, and satire. (978-1-62212-028-4)
- Weird Thoughts, a mixed anthology of 17 stories of science fiction, fantasy, and satire; plus seven essays on topics related to astronomy, including one describing the author's experience working on the Apollo Project. (978-1-946540-77-5)
Hamilton has also had astronomical articles in The Constellation, and science fiction in Aphelion, Bewildering Stories, and Changingthetimes.
- "JPL Small-Body Database Browser: 4897 Tomhamilton (1987 QD6)" (2017-06-05 last obs.). Jet Propulsion Laboratory. Retrieved 4 August 2017.
- "4897 Tomhamilton (1987 QD6)". Minor Planet Center. Retrieved 26 August 2016.
- Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Dailey, J.; et al. (November 2011). "Main Belt Asteroids with WISE/NEOWISE. I. Preliminary Albedos and Diameters". The Astrophysical Journal. 741 (2): 20. arXiv:1109.4096. Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. Retrieved 26 August 2016.
- "LCDB Data for (4897) Tomhamilton". Asteroid Lightcurve Database (LCDB). Retrieved 4 August 2017.
- "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 26 August 2016.
- http://sbpra.com/ThomasWmHamilton Books by Thomas Wm. Hamilton
- Hamilton Planetarium Scholarship Fund Inc.
- Asteroid Lightcurve Database (LCDB), query form (info)
- Dictionary of Minor Planet Names, Google books
- Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
- Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
- 4897 Tomhamilton at the JPL Small-Body Database