|Discovered by||E. F. Helin|
|Discovery site||Palomar Obs.|
|Discovery date||22 August 1987|
|MPC designation||(4897) Tomhamilton|
(of the Apollo program)
|1987 QD6 · 1971 QV1
1971 SB1 · 1990 BN1
|Orbital characteristics |
|Epoch 31 July 2016 (JD 2457600.5)|
|Uncertainty parameter 0|
|Observation arc||65.56 yr (23,945 days)|
|5.34 yr (1,950 days)|
|0° 11m 4.56s / day|
|Dimensions||±0.369 km 13.711|
4897 Tomhamilton, provisional designation 1987 QD6, is an 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.
The asteroid orbits the Sun at a distance of 2.7–3.4 AU once every 5 years and 4 months (1,950 days). Its orbit has an eccentricity of 0.12 and an inclination of 11° with respect to the ecliptic. Research showed that this minor planet was previously recorded on photographs and was logged as 1971 QV1. The first precovery was taken at the discovering observatory as early as 1950, extending the asteroid's observation arc by 37 years prior to its discovery.
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, the asteroid 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. As of 2016, however, the asteroid's shape and rotation period remain unknown.
The asteroid is 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. Naming citation was published on 4 October 2009 (M.P.C. 67215).
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.
Books by Hamilton
- Books on astronomical topics:
- Other books:
- Time for Patriots, a time travel adventure novel (ISBN 978-1-60693-224-7)
- The Mountain of Long Eyes, a satire (ISBN 978-1-62212-028-4)
- "JPL Small-Body Database Browser: 4897 Tomhamilton (1987 QD6)" (2016-03-05 last obs.). Jet Propulsion Laboratory. Retrieved 26 August 2016.
- "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: . Bibcode:2011ApJ...741...68M. doi:10.1088/0004-637X/741/2/68. Retrieved 26 August 2016.
- "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