Asteroids with Satellites Database--Johnston's Archive

1999 XY143

compiled by Wm. Robert Johnston
last updated 20 September 2014

--Orbital and physical data--

(See this page for definitions of quantities; source codes in brackets, see this link for full references; *A, *D, and *E indicate assumed, derived, and estimated values, respectively.)

dynamical type, primary: TNO, Cubewano


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 43.224 AU
orbital period P: 284.181 yr
(= 103797.0 d)
eccentricity e: 0.07770
perihelion distance q: 39.866 AU
aphelion distance Q: 46.582 AU
inclination i: 7.15229°
argument of perihelion ω: 83.02°
ascending node Ω: 255.39896°
mean anomaly M: 108.28°
perihelion passage TP: 1928 Nov 29
Epoch: 2014 May 23
data arc: 1999-2008 (26 obs.)
Earth MOID: 38.8633 AU
Jupiter Tisserand invariant TJ: 5.823
Neptune Tisserand invariant TN:3.07 [*D]


orbital data, secondary:
semimajor axis as: 2670 ± 70 km (separation) [G12b]
separation/primary radius as/rp:25 [*E]
separation/Hill radius as/rH:0.0040 [*E]
orbital period Ps: 14 d [*E]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 6 [MPC]
6.006 ± 0.565 [JPL]
slope parameter G: (0.15) [*A]
effective diameter dE: 278 km [*E]
geometric albedo: (0.09 ) [*A]
color index U-B: ?
color index B-V: ?
taxonomic type: ?
mass m: ?
density ρ: (1 g/cm3) [*A]
Hill radius rH: 660000 km [*E]

other data, primary:
diameter dp: 213 km [*E]
rotation period RPp: ?
amplitude in mag., rotational ΔM: ?
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 179 km [*E]
diameter ratio ds/dp: 0.839 [N09b]
component mag. difference ΔM: 0.38 [N09b]
rotation period RPs: ?

-- 1999 XY143 --discovery and notes:

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

Companion discovered 2008 Sep 19 by K. S. Noll, W. M. Grundy, S. D. Benecchi, and H. A. Levison using Hubble Space Telescope observations from Hubble Space Telescope. Announced 2009 Sep 24 [N09b].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2009, 2014 by Wm. Robert Johnston.
Last modified 20 September 2014.
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