It orbits the Sun at a distance of 4.57–5.95 AU once every 12 years and 1 month (4,408 days; semi-major axis of 5.26 AU). Its orbit has an eccentricity of 0.13 and an inclination of 21° with respect to the ecliptic.[4]
The asteroid was first observed as 1985 US2 at CERGA Observatory in October 1985. The body's observation arc begins with its official discovery observation at Palomar in January 1988.[1]
Physical characteristics
In the SDSS-based taxonomy, Halaesus is a D-type asteroid.[11]Pan-STARRS' survey also characterized it as a D-type, the most common spectral type among the Jupiter trojan population. It has a typical V–I color index of 0.90.[9][10]
In August 2015, observations by the Kepler space telescope gave two period determinations of 25.052 and 29.95 hours with an amplitude of 0.23 and 0.19 magnitude, respectively (U=2+/3-).[12][13]
Diameter and albedo
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Halaesus measures 50.77 kilometers in diameter and its surface has an albedo of 0.057.[7] The Collaborative Asteroid Lightcurve Link adopts an albedo of 0.057 and a diameter 50.77 of kilometers based on an absolute magnitude of 10.2.[9]
100+ largest Jupiter trojans
Largest Jupiter Trojans by survey(A) (mean-diameter in kilometers; YoD: Year of Discovery)
Note: missing data was completed with figures from the JPL SBDB (query) and from the LCDB (query form) for the WISE/NEOWISE and SIMPS catalogs, respectively. These figures are given in italics. Also, listing is incomplete above #100.