Asteroids with Satellites Database--Johnston's Archive

(617) Patroclus and Menoetius

compiled by Wm. Robert Johnston
last updated 21 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: Jupiter trojan, L5


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 5.217303510 AU
orbital period P: 11.91728581 yr
(= 4352.78864 d)
eccentricity e: 0.139513679
perihelion distance q: 4.48941830 AU
aphelion distance Q: 5.945188718 AU
inclination i: 22.0508739°
argument of perihelion ω: 308.408114°
ascending node Ω: 44.366003°
mean anomaly M: 54.110386°
perihelion passage TP: 2012 Aug 06.7470
Epoch: 2014 May 23
data arc: 1906-2014 (1038 obs.)
Earth MOID: 3.53506 AU
Jupiter Tisserand invariant TJ: 2.835


orbital data, secondary:
binary dynamical type:O [P07f]
semimajor axis as: 680 ± 20 km [M06b]
separation/primary radius as/rp:13 [*D]
separation/Hill radius as/rH:0.017 [*D]
orbital period Ps: 4.283 ± 0.004 d [M06b]
eccentricity es: 0.02 ± 0.02 [M06b]
normalized ang. mom. αL: 2.05 [P07f]

other data, system (combined):
absolute mag. H: 8.19 [MPC]
slope parameter G: (0.15) [*A]
effective diameter dE: 145 ± 15 km [M10b]
geometric albedo: 0.045 ± 0.009 [M10b]
color index U-B: 0.215 [T95a]
color index B-V: 0.677 [T95a]
taxonomic type: P (Tholen) [JPL]
mass m: 1.36x1018 ± 1.1x1017 kg [M06b]
density ρ: 0.8 ± 0.2/0.1 g/cm3[M06b]
Hill radius rH: 41000 km [*D]

other data, primary:
diameter dp: 106 ± 11 km [M10b]
rotation period RPp: 103.02 ± 0.4 h [M10b]
amplitude in mag., rotational ΔM: ?
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 98 ± 10 km [M10b]
diameter ratio ds/dp: 0.924 [M06b]
component mag. difference ΔM: 0.17 [*D]
rotation period RPs: ?

-- (617) Patroclus and Menoetius --discovery and notes:

Primary discovered 1906 Oct 17 from Heidelberg, Germany by A. Kopff. Alternate designation(s): 1906 VY, 1941 XC, 1962 NB. Permanent number assigned 1907 Nov .

Named 1907 for the Greek mythological character.

Companion discovered 2001 Sep 22 by W. J. Merline, L. M. Close, N. Siegler, D. Potter, C. R. Chapman, C. Dumas, F. Menard, and D. C. Slater using adaptive optics telescope observations from Gemini North Telescope, Mauna Kea, Hawaii, USA. Announced 2001 Oct 29 [M01a]. Provisional designation S/2001 (617) 1. Permanent designation I Menoetius, assigned 2006 Feb 02; named for the Greek mythological character [G06b].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2001-2006, 2014 by Wm. Robert Johnston.
Last modified 21 September 2014.
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