Discovered by K. EndateK. Watanabe MPC designation 6500 Kodaira Discovered 15 March 1993 Orbits Sun | Discovery date 15 March 1993 Minor planet category Mars-crosser Absolute magnitude 12.6 | |
Named after Keiichi Kodaira(astronomer) Alternative names 1993 ET · 1970 GE11973 ST5 People also search for 5692 Shirao, Sun, 4971 Hoshinohiroba | ||
6500 Kodaira, provisional designation 1993 ET, is a dark, rare-type, and eccentric asteroid and Mars-crosser, approximately 10 kilometers in diameter. It was discovered on 15 March 1993, by Japanese amateur astronomers Kin Endate and Kazuro Watanabe at Kitami Observatory in eastern Hokkaidō, Japan.
The carbonaceous and uncommon B-type asteroid, of which only a few dozen bodies are currently known, orbits the Sun at a distance of 1.6–3.9 AU once every 4 years and 7 months (1,670 days). Its orbit spans from within the orbit of Mars to the outer region of the asteroid belt, and has an eccentricity of 0.42 and an inclination of 29° with respect to the ecliptic. The first precovery was obtained at the Chilean Cerro El Roble Station in 1970, extending the asteroid's observation arc by 23 years prior to its discovery.
A rotational light-curve, obtained from photometric observations by American astronomer Robert Stevens at the Center for Solar System Studies in October 2014, gave a well-define rotation period of 7000540000000000000♠5.400±0.001 hours with a brightness variation of 0.78 in magnitude (U=3). Previous observations at Montgomery College Observatory (MCO), the Preston Gott and McDonald Observatories, and at the Palomar Transient Factory gave similar periods between 5.398 and 5.496 hours (U=3-/3-/2).
According to first-year results from the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, the asteroid measures 9.5 kilometers in diameter and its surface has an albedo of 0.15, while the Collaborative Asteroid Lightcurve Link assumes a low albedo of 0.057 and calculates a diameter of 16.8 kilometers.
The minor planet was named after Japanese astronomer and director of NAOJ, Keiichi Kodaira (b. 1937), whose interests lie in astrophysics and galactic physics. In the 1980s, he was head of IAU's commission of Theory of Stellar Atmospheres (comm. 36). He was also instrumental for the completion of the Subaru Telescope project, of which he was the scientific director since its inception. Naming citation was published on 1 June 1996 (M.P.C. 27331).