| Discovered by T. Kagawa
T. Urata MPC designation (9992) 1997 TG19 Observation arc 42.55 yr (15,541 days) Absolute magnitude 14.4 Discovery site Gekko Observatory | Discovery date 8 October 1997 Minor planet category Mars-crosser Discovered 8 October 1997 Orbits Sun Asteroid group Mars-crosser asteroid | |
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| Alternative names 1997 TG19 · 1974 HC1
1980 BD Discoverers Tetsuo Kagawa, Takeshi Urata People also search for Sun, 3686 Antoku, (31222) 1998 BD30 | ||
(9992) 1997 TG19 is a stony asteroid and eccentric Mars-crosser, approximately 4 kilometers in diameter. It was discovered on 8 October 1997, by Japanese astronomers Tetsuo Kagawa and Takeshi Urata at Gekko Observatory near Shizuoka, Japan.
The stony S-type asteroid orbits the Sun at a distance of 1.5–2.8 AU once every 3 years and 2 months (1,169 days). Its orbit has an eccentricity of 0.29 and an inclination of 3° with respect to the ecliptic. The first used observation was made at the Cerro El Roble Station in 1974, extending the asteroid's observation arc by 23 prior to its discovery.
Between 2006 and 2013, three rotational light-curves for this asteroid were obtained from photometric observations made at the Hunters Hill Observatory, Australia, the Ondřejov Observatory, Czech Republic, and the U.S. Palomar Transient Factory, California. They gave a well-defined, concurring rotation period of 7000574020000000000♠5.7402±0.0005 hours (best result) with a brightness amplitude of 0.42, 0.40 and 0.27 in magnitude, respectively (U=3/3/2).
According to the survey carried out by the Japanese Akari satellite, the asteroid's surface has an albedo of 0.13 and a diameter of 4.75 kilometers. The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 3.1 kilometers, as the higher the body's albedo (reflectivity), the shorter its diameter, at a constant absolute magnitude (brightness).