It orbits the Sun at a distance of 4.9–5.5 AU once every 11 years and 11 months (4,352 days; semi-major axis of 5.22 AU). Its orbit has an eccentricity of 0.06 and an inclination of 22° with respect to the ecliptic.[2]
1999 XS143 is an assumed, carbonaceous C-type asteroid. It has a high V–I color index of 1.00 (see table below).[7]
Rotation period
In September 2008, a rotational lightcurve of 1999 XS143 was obtained from photometric observations. Lightcurve analysis gave a rotation period of 5.72±0.02 hours with a brightness variation of 0.33 magnitude (U=2).[6][7]
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, 1999 XS143 between 50.96 kilometers in diameter and its surface has an albedo of 0.052,[5] while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for a carbonaceous asteroid of 0.057 and calculates a diameter of 46.30 kilometers based on an absolute magnitude of 10.4.[7] The object was neither observed by IRAS nor the Akari satellite.
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.
^ abMelita, M. D.; Duffard, R.; Williams, I. P.; Jones, D. C.; Licandro, J.; Ortiz, J. L. (June 2010). "Lightcurves of 6 Jupiter Trojan asteroids". Planetary and Space Science. 58 (7–8): 1035–1039. Bibcode:2010P&SS...58.1035M. doi:10.1016/j.pss.2010.03.009.