Discovery date 26 September 1987 Alternative names 1987 SG3 · 1951 NQ Discovered 26 September 1987 Orbits Sun Asteroid group Mars-crosser asteroid | MPC designation 9564 Jeffwynn Minor planet category Mars-crosser Absolute magnitude 14 Discovery site Palomar Observatory | |
Discovered by C. S. Shoemaker
E. M. Shoemaker Named after Jeffrey Wynn
(geophysicist) Discoverers Carolyn S. Shoemaker, Eugene Merle Shoemaker Similar Sun, 3554 Amun, Comet Shoemak, 129P/Shoemaker–Levy, 118P/Shoemaker–Levy | ||
9564 Jeffwynn, provisional designation 1987 SG3, is a stony and eccentric asteroid, classified as a Mars-crosser, that measures approximately 4.7 kilometers in diameter. It was discovered by American astronomer couple Carolyn and Eugene Shoemaker at the U.S. Palomar Observatory in California, on 26 September 1987.
The S-type asteroid orbits the Sun at a distance of 1.6–3.1 AU once every 3 years and 7 months (1,307 days). Its orbit has an eccentricity of 0.32 and an inclination of 22° with respect to the ecliptic. The first precovery was taken at Palomar Observatory in 1951, extending the asteroid's observation arc by 36 years prior to its discovery.
In September 2012, a rotational light-curve was obtained from photometric observations by U.S. astronomer Brian D. Warner at his Palmer Divide Observatory, Colorado. It gave a well-defined rotation period of 7000303500000000000♠3.035±0.001 hours with a brightness variation of 0.16 in magnitude (U=3). The Collaborative Asteroid Lightcurve Link calculates a diameter of 4.7 kilometers based on an absolute magnitude of 14.0 and an assumed albedo for stony asteroids of 0.20.
The minor planet was named in honor of American Jeffrey C. Wynn, research geophysicist with the United States Geological Survey, described as a "humorous, curious, inventive, adventurous geophysicist", who examined the Saudi Arabian Wabar craters on several expeditions in 1994 and 1995, together with Eugene Shoemaker, after whom the minor planet 2074 Shoemaker is named. Wynn's research included mapping the seafloor, analyzing terrestrial minerals, and studying aquifers and archaeological sites. He also observed with the comet-discovering Shoemaker-Levy team. Naming citation was published on 23 November 1999 (M.P.C. 36948).