Asteroids with Satellites Database--Johnston's Archive

(55637) 2002 UX25

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: 42.7846 AU
orbital period P: 279.859 yr
(= 102218.6 d)
eccentricity e: 0.144846
perihelion distance q: 36.5874 AU
aphelion distance Q: 48.9818 AU
inclination i: 19.43799°
argument of perihelion ω: 276.832°
ascending node Ω: 204.635741°
mean anomaly M: 293.896°
perihelion passage TP: 2065 Oct 11
Epoch: 2014 May 23
data arc: 1991-2013 (74 obs.)
Earth MOID: 35.6599 AU
Jupiter Tisserand invariant TJ: 5.473
Neptune Tisserand invariant TN:2.93 [*D]


orbital data, secondary:
semimajor axis as: 4770 ± 40 km [B13b]
separation/primary radius as/rp:14 [*D]
separation/Hill radius as/rH:0.0032 [*D]
orbital period Ps: 8.309 ± 0.0002 d [B13b]
eccentricity es: 0.17 ± 0.03 [B13b]
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 3.8 [MPC]
3.87 ± 0.02 [F13a]
slope parameter G: (0.15) [*A]
effective diameter dE: 697.2 ± 23/24.5 km [F13a]
geometric albedo: 0.107 ± 0.005/0.008 [F13a]
color index U-B: 0.26 [J07a]
color index B-V: 0.98 [J07a]
color index V-R:0.54 ± 0.03 [J07a]
color index B-R:1.52 [J07a]
color index V-I:1.13 ± 0.05 [D07c]
color index R-J:1.28 [D07c]
color index V-J:1.82 ± 0.09 [D07c]
color index J-H:0.4 ± 0.05 [D07c]
color index V-H:2.22 [D07c]
taxonomic type: RR (G-mode) [P10a]
mass m: 1.25x1020 ± 3x1018 kg [B13b]
density ρ: 0.82 ± 0.11/0.11 g/cm3[B13b]
Hill radius rH: 1500000 km [*D]

other data, primary:
diameter dp: 665 ± 29 km [F13a]
rotation period RPp: 14.382 ± 0.001 h [R05a]
amplitude in mag., rotational ΔM: 0.21 ± 0.06 [R05a]
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 210 ± 30 km [F13a]
diameter ratio ds/dp: 0.316 ± 0.029 [B07d]
component mag. difference ΔM: 2.5 ± 0.2 [I8812]
rotation period RPs: ?

-- (55637) 2002 UX25 --discovery and notes:

Primary discovered 2002 Oct 30 from Kitt Peak Observatory, Arizona, USA by Spacewatch. Linked to prediscovery observations from 1991 Oct 12. Permanent number assigned 2003 Feb 16.

Companion discovered 2005 Aug 26 by M. E. Brown and T.-A. Suer using Hubble Space Telescope observations from Hubble Space Telescope. Announced 2007 Feb 22 [B07d].

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© 2007, 2014 by Wm. Robert Johnston.
Last modified 20 September 2014.
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