Discovered by E. F. Helin
S. J. Bus MPC designation 3240 Laocoon Absolute magnitude 10 Discovery site Palomar Observatory | Discovery date 7 November 1978 Discovered 7 November 1978 Orbits Sun Asteroid group Jupiter trojan | |
Pronunciation leɪˈɒkoʊɒn
(lay-ok'-oe-on) Named after Laocoön
(Greek mythology) Alternative names 1978 VG6 · 1976 SA9
1976 SL2 · 1978 WS12 Discoverers Schelte J. Bus, Eleanor F. Helin Similar Jupiter trojan, 2100 Ra‑Shalom, 4015 Wilson–Harrington, Sun | ||
3240 Laocoon (LAY-ok'-OE-on), provisional designation 1978 VG6, is a carbonaceous Jupiter trojan from the Trojan camp, approximately 51 kilometers in diameter. It was discovered on 7 November 1978, by American astronomers Eleanor Helin and Schelte Bus at the U.S. Palomar Observatory in California.
The C-type asteroid is also classified as a D-type by Pan-STARRS' large-scale survey. It resides in the Trojan camp of Jupiter's L5 Lagrangian point, which lies 60° behind the gas giant's orbit, and orbits the Sun at a distance of 4.6–5.9 AU once every 11 years and 12 months (4,377 days). Its orbit has an eccentricity of 0.13 and an inclination of 2° with respect to the ecliptic. The first observation was made at Crimea–Nauchnij in 1976, extending the asteroid's observation arc by 2 years prior to its discovery.
In April 1996, Laocoon was observed by Italian astronomer Stefano Mottola using the now decommissioned Bochum 0.61-metre Telescope at ESO's La Silla Observatory in Chile. The light-curve gave a rotation period of 7001113120000000000♠11.312±0.024 hours with a brightness variation of 6999550000000000000♠0.55±0.02 in magnitude (U=2+).
According to the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, the Jovian asteroid measures 51.7 kilometers in diameter and its surface has an albedo of 0.060, while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a diameter of 50.8 kilometers, based on an absolute magnitude of 10.2.
The minor planet was named after the Troyan priest Laocoön from Greek mythology. He and both his sons were killed by serpents serpents sent by the gods because he tried to expose the Greek's deception of the Trojan Horse. Naming citation was published on 7 September 1987 (M.P.C. 12210).