5264 Telephus

Classification and orbit

Telephus is a dark Jovian asteroid orbiting in the leading Greek camp at Jupiter's Lagrangian point, 60° ahead of the Gas Giant's orbit in a 1:1 resonance (see Trojans in astronomy). It is also a non-family asteroid in the Jovian background population.

It orbits the Sun at a distance of 4.6–5.8 AU once every 11 years and 11 months (4,342 days; semi-major axis of 5.21 AU). Its orbit has an eccentricity of 0.11 and an inclination of 34° concerning the ecliptic. The asteroid was first observed as ** at the Purple Mountain Observatory in January 1965. The body's observation arc begins with a precovery taken at Palomar in January 1989, more than two years before its official discovery observation.

Physical characteristics

In both the Tholen- and SMASS-like taxonomy of the Small Solar System Objects Spectroscopic Survey (S3OS2), Telephus is a D-type asteroid. In the SDSS-basedtaxonomy, it is also a D-type, while the Collaborative Asteroid Lightcurve Link (CALL) assumes it to be a C-type.

Rotation period

In June 1994, photometric observations of this asteroid by astronomers Stefano Mottola and Anders Erikson with the Dutch 0.9-metre Telescope at ESO's La Silla Observatory, Chile, were used to build a lightcurve. It showed a rotation period of 9.518 hours with a brightness amplitude of magnitude ().

In May 2015, Telephus was observed in Chile using the 4-meter Víctor M. Blanco Telescope and DECam with a red filter in Chile. The lightcurve had a concurring period of 9.540 hours and a brightness variation of 0.20 in magnitude (). In May 2016, follow-up observation by Robert Stephens and Daniel Coley at the Center for Solar System Studies, California, and Linda French at Wesleyan University gave the so-far best-rated period of hours with an amplitude of 0.47 (). Due to its higher-than-usual brightness variation, this Jovian asteroid is likely to have a non-spherical shape.

Diameter and albedo

According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, the asteroid measures between 68.47 and 81.38 kilometers in diameter and its surface has an albedo between 0.043 and 0.072. CALL agrees with the results obtained by IRAS, and derives an albedo of 0.0571 with a diameter of 73.33 kilometers, based on an absolute magnitude of 9.4.

the Naming

This minor planet was named from Greek mythology after the King Telephus. He is the grandson of Zeus and son of Heracles, after whom the Apollo near-Earth asteroids 5731 Zeus and 5143 Heracles were named, respectively. Telephus was the son-in-law of King Priam of Troy, but fought with the Greeks in the Trojan War. The official naming citation was published by the Minor Planet Center on 12 July 1995 (M.P.C. 25444).

Notes

References

References

1. Noah Webster (1884) ''A Practical Dictionary of the English Language''