Asteroids with Satellites Database--Johnston's Archive

(612549) 2003 HG57

compiled by Wm. Robert Johnston
last updated 10 April 2022

--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: 43.677 AU
orbital period P: 288.657 yr
(= 105432.1 d)
eccentricity e: 0.03179
perihelion distance q: 42.288 AU
aphelion distance Q: 45.065 AU
inclination i: 2.09608°
argument of perihelion ω: 223.16°
ascending node Ω: 36.3070°
mean anomaly M: 316.65°
perihelion passage TP: 2049 Feb 24
Epoch: 2014 May 23
data arc: 2003-2013 (19 obs.)
Earth MOID: 41.2731 AU
Jupiter Tisserand invariant TJ: 5.907
Neptune Tisserand invariant TN:3.10 [*D]


orbital data, secondary:
semimajor axis as: 13200 ± 50 km (separation) [G12b]
separation/primary radius as/rp:170 [*E]
separation/Hill radius as/rH:0.024 [*E]
orbital period Ps: 210 d [*E]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 6.5 [MPC]
slope parameter G: (0.15) [*A]
effective diameter dE: 221 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: 550000 km [*E]

other data, primary:
diameter dp: 156 km [*E]
rotation period RPp: ?
amplitude in mag., rotational ΔM: ?
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 156 km [*E]
diameter ratio ds/dp: 1 [G12b]
component mag. difference ΔM: 0.0 [G12b]
rotation period RPs: ?

-- (612549) 2003 HG57 --discovery and notes:

Primary discovered 2003 Apr 26 from Mauna Kea Observatory, Hawaii, USA by ?. Permanent number assigned 28 Mar 2022.

Companion discovered 2010 Dec 22 using Hubble Space Telescope observations from Hubble Space Telescope. Announced 2012.

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2012-2014, 2022 by Wm. Robert Johnston.
Last modified 10 April 2022.
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