Asteroids with Satellites Database--Johnston's Archive

2004 HK79

compiled by Wm. Robert Johnston
last updated 17 August 2019

--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: 44.231 AU
orbital period P: 294.17 yr
(= 107445.8 d)
eccentricity e: 0.08617
perihelion distance q: 40.4197 AU
aphelion distance Q: 48.042 AU
inclination i: 1.94333°
argument of perihelion ω: 181.72°
ascending node Ω: 69.0275°
mean anomaly M: 340.7°
perihelion passage TP: 2035 Feb 03.8
Epoch: 2019 Apr 27
data arc: 2004-2015 (22 obs.)
Earth MOID: 39.4054 AU
Jupiter Tisserand invariant TJ: 5.924


orbital data, secondary:
semimajor axis as: 3600 ± 70 km (separation) [G19c]
separation/primary radius as/rp:56 [*E]
separation/Hill radius as/rH:0.008 [*E]
orbital period Ps: 41 d [*E]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 6.9 [MPC]
7.5 ± 0.5 [G19c]
slope parameter G: (0.15) [*A]
effective diameter dE: 183 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: 480000 km [*E]

other data, primary:
diameter dp: 129 km [*E]
rotation period RPp: ?
amplitude in mag., rotational ΔM: ?
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 129 km [*E]
diameter ratio ds/dp: 1.0 [*D]
component mag. difference ΔM: 0.0 [G19c]
rotation period RPs: ?

-- 2004 HK79 --discovery and notes:

Primary discovered 2004 Apr 26 from Mauna Kea Observatory, Hawaii, USA by B. Gladman.

Companion discovered 2019 Jun 04 using Hubble Space Telescope observations. Announced 2019 Aug [G19c].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2019 by Wm. Robert Johnston.
Last modified 17 August 2019.
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