Asteroids with Satellites Database--Johnston's Archive

1999 OJ4

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


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 37.9154 AU
orbital period P: 233.470 yr
(= 85275.0 d)
eccentricity e: 0.02647
perihelion distance q: 36.9116 AU
aphelion distance Q: 38.9192 AU
inclination i: 4.00489°
argument of perihelion ω: 298.80°
ascending node Ω: 127.5415°
mean anomaly M: 274.29°
perihelion passage TP: 2069 Dec 23
Epoch: 2014 May 23
data arc: 1999-2008 (63 obs.)
Earth MOID: 35.9264 AU
Jupiter Tisserand invariant TJ: 5.521
Neptune Tisserand invariant TN:3.03 [*D]


orbital data, secondary:
semimajor axis as: 3267 ± 60 km [G09a]
separation/primary radius as/rp:87 [*D]
separation/Hill radius as/rH:0.015 [*D]
orbital period Ps: 84.12 ± 0.038 d [G09a]
eccentricity es: 0.365 ± 0.012 [G09a]
inclination is:53.8° ± 1.2° [G09a]
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 7.1 [MPC]
7.344 ± 0.012 [G09a]
slope parameter G: (0.15) [*A]
effective diameter dE: 104 km [*D]
geometric albedo: 0.215 ± 0.095/0.095 [G09a]
color index U-B: ?
color index B-V: 0.988 [P04a]
color index V-R:0.682 ± 0.05 [P04a]
color index B-R:1.675 ± 0.077 [P04a]
color index V-I:1.2 [P04a]
taxonomic type: RR? (G-mode) [B05b]
mass m: 3.91x1017 ± 2.2x1016 kg [G09a]
density ρ: (1 ± 1/0.5 g/cm3) [*A]
Hill radius rH: 220000 km [*D]

other data, primary:
diameter dp: 75 ± 17 km [G09a]
color index V-I:1.25 ± 0.11 [B08d]
rotation period RPp: ?
amplitude in mag., rotational ΔM: ?
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 72 ± 16 km [*D]
diameter ratio ds/dp: 0.96 ± 0.009 [G09a]
component mag. difference ΔM: 0.088 ± 0.02 [G09a]
color index V-I:1.37± 0.24 [B08d]
rotation period RPs: ?

-- 1999 OJ4 --discovery and notes:

Primary discovered 1999 Jul 18 from Mauna Kea Observatory, Hawaii, USA by ?.

Companion discovered 2002 Oct 04 using Hubble Space Telescope observations from Hubble Space Telescope. Announced 2005 Oct 06.

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2005-2008, 2014 by Wm. Robert Johnston.
Last modified 20 September 2014.
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