Asteroids with Satellites Database--Johnston's Archive

(43008) 1999 UD31

compiled by Wm. Robert Johnston
last updated 7 September 2015

--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


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 2.348350145 AU
orbital period P: 3.59868868 yr
(= 1314.445865 d)
eccentricity e: 0.18885934
perihelion distance q: 1.90484229 AU
aphelion distance Q: 2.791858003 AU
inclination i: 1.9673061°
argument of perihelion ω: 203.64521°
ascending node Ω: 126.24226°
mean anomaly M: 110.827253°
perihelion passage TP: 2013 Oct 30.343265
Epoch: 2014 Dec 09
data arc: 1996-2015 (704 obs.)
Earth MOID: 0.894669 AU
Jupiter Tisserand invariant TJ: 3.534


orbital data, secondary:
semimajor axis as: ?
orbital period Ps: ?
eccentricity es: 0 [P15f]
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 15.6 [MPC]
slope parameter G: (0.15) [*A]
effective diameter dE: 2.5 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: 360 km [*E]

other data, primary:
diameter dp: 2.4 km [*E]
rotation period RPp: 2.9 ± 0.5 h [P15f]
amplitude in mag., rotational ΔM: ?
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 0.8 km [*E]
diameter ratio ds/dp: 0.35 ± 0.1 [P15f]
component mag. difference ΔM: 2.3 [*D]
rotation period RPs: ?

-- (43008) 1999 UD31 --discovery and notes:

Primary discovered 1999 Oct 31 from Kitt Peak Observatory, Arizona, USA by Spacewatch Program. Alternate designation(s): 1996 XT18, 1999 RM105. Linked to prediscovery observations from 1996 Dec 12. Permanent number assigned 2002 Jun 24.

Companion discovered 2014 by Pravec, P., P. Scheirich, P. Kusnirak, K. Hornoch, and A. Galad using lightcurve observations. Announced 2015 Aug 05 [P15f].

--Links, more technical:

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--Links to ADS abstracts:


© 2015 by Wm. Robert Johnston.
Last modified 7 September 2015.
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