Discovered by E. F. Helin MPC designation 4897 Tomhamilton Discovered 22 August 1987 Orbits Sun | Discovery date 22 August 1987 Minor planet category main-belt Absolute magnitude 12 Discoverer Eleanor F. Helin Asteroid group Asteroid belt | |
Alternative names 1987 QD6 · 1971 QV11971 SB1 · 1990 BN1 Similar 4015 Wilson–Harrington, Sun, 6489 Golevka, 9969 Braille, 4769 Castalia |
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.