Discovery date 19 September 1985 Minor planet category main-belt · Eunomia Orbits Sun Asteroid group Asteroid belt | MPC designation 9549 Akplatonov Discovered 19 September 1985 Asteroid family Eunomia family | |
Discovered by N. Chernykh
L. Chernykh Named after Aleksandr Platonov
(computational mathematician) Alternative names 1985 SM2 · 1981 TU1
1987 BP3 · 1992 JK3 Discovery site Crimean Astrophysical Observatory Discoverers Nikolai Chernykh, Lyudmila Chernykh Similar 2577 Litva, Sun, 390 Alma, 85 Io | ||
9549 Akplatonov, provisional designation 1985 SM2, is a stony Eunomia asteroid from the middle region of the asteroid belt, approximately 9 kilometers in diameter. It was discovered on 19 September 1985, by Soviet–Russian astronomer couple Nikolai and Lyudmila Chernykh at the Crimean Astrophysical Observatory, Nauchnyj, on the Crimean peninsula.
The asteroid is a member of the Eunomia family, a large group of stony S-type asteroids and the most prominent family in the intermediate main-belt. It orbits the Sun at a distance of 2.3–2.9 AU once every 4 years and 3 months (1,538 days). Its orbit has an eccentricity of 0.11 and an inclination of 11° with respect to the ecliptic. The first precovery was taken at the discovering observatory in 1981, extending the asteroid's observation arc by 4 years prior to its discovery.
According to the survey carried out by the NEOWISE mission of NASA's space-based Wide-field Infrared Survey Explorer, the asteroid measures 8.2 kilometers in diameter and its surface has an albedo of 0.29, while the Collaborative Asteroid Lightcurve Link (CALL) assumes a standard albedo for stony asteroids of 0.21, and calculates a diameter of 9.2 kilometers.
A rotational light-curve was obtained from photometric observations using the 0.9-meter SARA telescope at Kitt Peak National Observatory in May 2009. It showed a rotation period of 7000284310000000000♠2.8431±0.0004 hours with a brightness amplitude of 0.15 in magnitude (U=3-). A second, fragmentary light-curve from observations at Palomar Transient Factory in August 2010, gave a period of 4.7 hours and has received a low quality rating by CALL (U=1).
The minor planet was named in honor of Aleksandr Konstantinovich Platonov (b. 1931), a Russian computational mathematician, roboticist, and astrodynamicist, long-time member at the Keldysh Institute of Applied Mathematics. He pioneered the research in walking robots, the computation of satellite orbits around Earth, and the guidance of the flight path of spacecrafts in the Solar System. Naming citation was published on 24 June 2002 (M.P.C. 46009).