Asteroids with Satellites Database--Johnston's Archive

(82157) 2001 FM185

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: 38.718 AU
orbital period P: 240.920 yr
(= 87996.1 d)
eccentricity e: 0.05811
perihelion distance q: 36.468 AU
aphelion distance Q: 40.968 AU
inclination i: 5.3615°
argument of perihelion ω: 110.72°
ascending node Ω: 150.7203°
mean anomaly M: 286.12°
perihelion passage TP: 2063 Oct 30
Epoch: 2014 May 23
data arc: 2001-2008 (20 obs.)
Earth MOID: 35.4562 AU
Jupiter Tisserand invariant TJ: 5.557
Neptune Tisserand invariant TN:3.03 [*D]

orbital data, secondary:
semimajor axis as: 3130 ± 90 km (separation) [G12b]
separation/primary radius as/rp:45 [*E]
separation/Hill radius as/rH:0.0079 [*E]
orbital period Ps: 33 d [*E]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 6.9 [MPC]
7.2 ± 0.5 [G12b]
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: 400000 km [*E]

other data, primary:
diameter dp: 138 km [*E]
rotation period RPp: ?
amplitude in mag., rotational ΔM: ?
pole direction Β, λ: ? , ?

other data, secondary:
diameter ds: 120 km [*E]
diameter ratio ds/dp: 0.867 [G12b]
component mag. difference ΔM: 0.31 [G12b]
rotation period RPs: ?

-- (82157) 2001 FM185 --discovery and notes:

Primary discovered 2001 Mar 26 from Kitt Peak Observatory, Arizona, USA by M. W. Buie. Permanent number assigned 2004 May 04.

Companion discovered 2008 Nov 28 using Hubble Space Telescope observations from Hubble Space Telescope. Announced 2011.

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:

© 2011, 2014 by Wm. Robert Johnston.
Last modified 20 September 2014.
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