1999 XY143

compiled by Wm. Robert Johnston
last updated 6 December 2009

Orbital elements and other data (Assumed or derived values in parenthesis, my estimates in italics and parenthesis. Source identifications in brackets, see this link for sources):

orbital data, primary (osculating elements) [JPL]:
semimajor axis a: 42.9656 AU
orbital period P: 281.64 y (=102,868 d)
eccentricity e: 0.08339
perihelion distance q: 39.3827 AU
aphelion distance Q: 46.5484 AU
inclination i: 7.17166°
argument of perihelion omega: 79.708°
ascending node OMEGA: 255.44005°
mean anomaly M: 105.560°
perihelion passage TP: 1927-06-06.0
Epoch: 04 JAN 2010
data arc: 1999-2008 (26 obs.)

orbital data, secondary:
semimajor axis a: (~2,600 km separation)
semimajor axis/primary radius a/Rp: (25?)
orbital period P: (~14 d?)
eccentricity e: ?

other data, primary:
diameter: (212 km?)
absolute magnitude H: 6.0059±0.5654 [JPL]
rotation period: ?
amplitude delta M: ?
color index B-V: ?
color index V-R: ?
color index R-I: ?
slope parameter G: (0.15) assumed
geometric albedo: (0.09) assumed
mass: ?
density: ?
type: ?

other data, secondary:
diameter: (178 km?)
diameter ratio Ds/Dp: (0.84)
component magnitude difference: 0.38 [I9075]
rotation period: ?

--1999 XY143--discovery and notes:

Primary discovered by C. W. Hergenrother on 14 December 1999 from Whipple Observatory, Mt. Hopkins, Arizona.

Companion discovered by Knoll et al. from Hubble Space Telescope observations; announced 24 September 2009.

See more information and links at Asteroid/Comet Connection Catchall Catalog page

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2009 by Wm. Robert Johnston.
Last modified 6 December 2009.
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