Discovered by E. Bowell MPC designation 3255 Tholen Minor planet category Mars-crosser Absolute magnitude 13.6 Discoverer Edward L. G. Bowell Asteroid group Mars-crosser asteroid | Discovery date 2 September 1980 Alternative names 1980 RA · 1969 SD Discovered 2 September 1980 Orbits Sun Discovery site Anderson Mesa Station | |
Named after David J. Tholen
(astronomer) People also search for 3343 Nedzel, 3217 Seidelmann | ||
3255 Tholen, provisional designation 1980 RA, is a stony asteroid, Mars-crosser and relatively fast rotator, that measures approximately 6 kilometers in diameter. It was discovered on 2 September 1980, by American astronomer Edward Bowell at Lowell's Anderson Mesa Station in Flagstaff, Arizona.
The S-type asteroid orbits the Sun at a distance of 1.5–3.2 AU once every 3 years and 8 months (1,335 days). Its orbit has an eccentricity of 0.36 and an inclination of 21° with respect to the ecliptic. The first observation was made at the Argentinian El Leoncito site in 1969, extending the asteroid's observation arc by 11 years prior to its discovery.
According to the space-based survey carried out by the Japanese Akari satellite and NASA's NEOWISE mission, the asteroid measures 4.0 and 6.8 kilometers in diameter, and its surface has an albedo of 0.14 and 0.34, respectively, while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 5.1 kilometers, based on an absolute magnitude of 13.84.
Several rotational light-curves were obtained for this asteroid from photometric observations. In September 2013, Italian astronomer Andrea Ferrero at the Bigmuskie Observatory (B88) in Mombercelli, Italy, derived a rotation period of 7000294700000000000♠2.947±0.001 hours with a brightness variation of 0.11 in magnitude (U=2), while two month later, in November 2013, astronomer Brian A. Skiff obtained two light-curves that both gave a period of 2.95 and an amplitude of 0.24 and 0.28 in magnitude, respectively (U=3-/3-). The results supersede two older light-curves from 1991 and 2002, that gave a period of 7000300000000000000♠3±1 and 6 hours, respectively (U=1/1).
The minor planet was named after David J. Tholen (b. 1955), a discoverer of minor planets and planetary scientist at the Institute for Astronomy of the University of Hawaii, known for his eight-color taxonomic scheme on minor planets. Naming citation was published on 14 April 1987 (M.P.C. 11749).