Asteroids with Satellites Database--Johnston's Archive

(11217) 1999 JC4

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: main belt asteroid, inner


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 1.943872983 AU
orbital period P: 2.710254212 yr
(= 989.920351 d)
eccentricity e: 0.069681447
perihelion distance q: 1.80842110 AU
aphelion distance Q: 2.079324866 AU
inclination i: 19.2921289°
argument of perihelion ω: 69.572644°
ascending node Ω: 224.687059°
mean anomaly M: 128.393813°
perihelion passage TP: 2013 Jun 03.9454
Epoch: 2014 May 23
data arc: 1978-2014 (552 obs.)
Earth MOID: 0.850997 AU
Jupiter Tisserand invariant TJ: 3.828


orbital data, secondary:
semimajor axis as: 6.2 km [*E]
separation/primary radius as/rp:3.8 [*E]
separation/Hill radius as/rH:0.013 [*E]
orbital period Ps: 0.7988 ± 0.0004 d [W14a]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 15 [MPC]
slope parameter G: (0.15) [*A]
effective diameter dE: 3.3 km [*E]
geometric albedo: (0.16 ) [*A]
color index U-B: ?
color index B-V: ?
taxonomic type: ?
mass m: ?
density ρ: (1.6 g/cm3) [*A]
Hill radius rH: 460 km [*E]

other data, primary:
diameter dp: 3.3 km [*E]
rotation period RPp: 4.8219 ± 0.0004 h [W14a]
amplitude in mag., rotational ΔM: 0.11 ± 0.01 [W14a]
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: ?
diameter ratio ds/dp: ?
component mag. difference ΔM: ?
rotation period RPs: ?

-- (11217) 1999 JC4 --discovery and notes:

Primary discovered 1999 May 10 from Socorro, New Mexico, USA by LINEAR. Alternate designation(s): 1978 WZ20, 1989 UM2. Linked to prediscovery observations from 1978 Nov 28. Permanent number assigned 1999 Jul 28.

Companion discovered 2013 Jul 07 by B. D. Warner using lightcurve observations from Palmer Divide Observatory, Colorado Springs, Colorado, USA. Announced 2013 Dec [W14a].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2014 by Wm. Robert Johnston.
Last modified 21 September 2014.
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