Asteroids with Satellites Database--Johnston's Archive

2000 QL251

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, 1:2 resonance


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 47.695 AU
orbital period P: 329.393 yr
(= 120310.6 d)
eccentricity e: 0.21434
perihelion distance q: 37.4717 AU
aphelion distance Q: 57.918 AU
inclination i: 3.67089°
argument of perihelion ω: 99.299°
ascending node Ω: 223.3548°
mean anomaly M: 32.394°
perihelion passage TP: 1984 Oct 01
Epoch: 2014 May 23
data arc: 2000-2008 (43 obs.)
Earth MOID: 36.4603 AU
Jupiter Tisserand invariant TJ: 6.011
Neptune Tisserand invariant TN:3.09 [*D]


orbital data, secondary:
semimajor axis as: 5002 ± 27 km [G09a]
separation/primary radius as/rp:68 [*D]
separation/Hill radius as/rH:0.011 [*D]
orbital period Ps: 56.451 ± 0.025 d [G09a]
eccentricity es: 0.4871 ± 0.0065 [G09a]
inclination is:127.78° ± 0.62° [G09a]
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 6.6 [MPC]
7.148 ± 0.016 [G09a]
slope parameter G: (0.15) [*A]
effective diameter dE: 206 km [*D]
geometric albedo: 0.07 ± 0.03/0.03 [G09a]
color index U-B: ?
color index B-V: 0.87 [S12f]
color index V-R:0.49 ± 0.03 [S12f]
color index B-R:1.36 ± 0.04 [S12f]
color index V-I:0.97 [S12f]
taxonomic type: ?
mass m: 3.11x1018 ± 5.1x1016 kg [G09a]
density ρ: (1 ± 1/0.5 g/cm3) [*A]
Hill radius rH: 450000 km [*D]

other data, primary:
diameter dp: 148 ± 34 km [G09a]
color index V-I:0.85 ± 0.09 [B08d]
rotation period RPp: ?
amplitude in mag., rotational ΔM: ?
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 143 ± 33 km [*D]
diameter ratio ds/dp: 0.967 ± 0.021 [G09a]
component mag. difference ΔM: 0.073 ± 0.048 [G09a]
color index V-I:0.98± 0.12 [B08d]
rotation period RPs: ?

-- 2000 QL251 --discovery and notes:

Primary discovered 2000 Aug 25 from Cerro Tololo Observatory, La Serena, Chile by M. W. Buie.

Companion discovered 2006 Jul 25 by K. S. Noll, D. C. Stephens, W. M. Grundy, and H. F. Levison using Hubble Space Telescope observations from Hubble Space Telescope. Announced 2006 Sep 12 [N06e].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2006-2008, 2014 by Wm. Robert Johnston.
Last modified 20 September 2014.
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