2241 Alcathous
2241 Alcathous is a large Jupiter trojan from the Trojan camp, approximately in diameter. It was discovered on 22 November 1979, by American astronomer Charles Kowal at the Palomar Observatory in southern California, United States. The dark D-type asteroid belongs to the 20 largest Jupiter trojans and has a rotation period of 7.7 hours. It was named after Alcathous from Greek mythology.
Orbit and classification
Alcathous is a dark Jovian asteroid orbiting in the trailing Trojan camp at Jupiter's Lagrangian point, 60° behind its orbit in a 1:1 resonance. It is also a non-family asteroid of the Jovian background population.It orbits the Sun at a distance of 4.8–5.5 AU once every 11 years and 10 months. Its orbit has an eccentricity of 0.07 and an inclination of 17° with respect to the ecliptic. The body's observation arc begins with a precovery taken at Palomar in June 1950, more than 29 years prior to its official discovery observation.
Physical characteristics
In the Tholen, Barucci and Tedesco taxonomy, Alcathous is classified as a dark D-type asteroid. It is the 8th largest of all 46 D-type asteroids in the Tholen classification.Rotation period
A large number rotational lightcurves have been obtained since December 1991, when Alcathous was first observed by Stefano Mottola with the Loiano 1.52-meter telescope at Bologna Observatory, Italy. In 1994, the asteroid's rotation period was also measured by Giovanni de Sanctis and collaborators.Several photometric observations between 2010 and 2017, by Daniel Coley and Robert Stephens at the Center for [Solar System Studies] and at GMARS, also include the so-far best-rated period of 7.689 hours with a brightness amplitude of 0.22 magnitude.