Discovered by P. Wild MPC designation 2005 Hencke Orbits Sun Asteroid group Asteroid belt | Discovery date 2 September 1973 Alternative names 1973 RA Discovered 2 September 1973 | |
Similar 625 Xenia, 9081 Hideakianno, Asteroid belt, 17 Thetis, 274301 Wikipedia | ||
2005 Hencke, provisional designation 1973 RA, is a stony Eunomia asteroid from the middle region of the asteroid belt, approximately 10 kilometers in diameter. It was discovered by Swiss astronomer Paul Wild at Zimmerwald Observatory near Bern, Switzerland, on 2 September 1973.
The asteroid is a member of the Eunomia family, a large group of S-type asteroids and the most prominent family in the intermediate main-belt. It orbits the Sun at a distance of 2.2–3.1 AU once every 4 years and 3 months (1,550 days). Its orbit has an eccentricity of 0.17 and an inclination of 12° with respect to the ecliptic. As no precoveries were taken, the asteroid's observation arc begins with its discovery in 1973.
In October 2007, a rotational light-curve was obtained for this asteroid from photometric observations taken by U.S. astronomer James W. Brinsfield at the Via Capote Observatory in Thousand Oaks, California (G69). The light-curve gave a rotation period of 7001101860000000000♠10.186±0.006 hours with a brightness amplitude of 0.08 in magnitude (U=2).
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, the asteroid measures 9.4 kilometers in diameter and its surface has an albedo of 0.27, while the Collaborative Asteroid Lightcurve Link assumes an albedo of 0.21, derived from the family's largest member and namesake, 15 Eunomia, and calculates a diameter of 10.5 kilometers.
The minor planet was named in honor of German amateur astronomer Karl Ludwig Hencke (1793–1866), a postmaster by profession, who discovered the main-belt asteroids 5 Astraea and 6 Hebe in 1845 and 1847, respectively. Naming citation was published before November 1977 (M.P.C. 4238).