Asteroids with Satellites Database--Johnston's Archive

(11549) 1992 YY

compiled by Wm. Robert Johnston
last updated 28 October 2023

--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: 2.5314934002 AU
orbital period P: 4.027851046 yr
(= 1471.1725944 d)
eccentricity e: 0.0879288392
perihelion distance q: 2.308902124 AU
aphelion distance Q: 2.7540846764 AU
inclination i: 11.442628321°
argument of perihelion ω: 327.0838219°
ascending node Ω: 268.21432236°
mean anomaly M: 101.6150331°
perihelion passage TP: 2022 Jul 24.740967
Epoch: 2023 Sep 13
data arc: 1959-2023 (3262 obs.)
Earth MOID: 1.30303 AU
Jupiter Tisserand invariant TJ: 3.417


orbital data, secondary:
semimajor axis as: 25 km [*E]
separation/primary radius as/rp:4.9 [*E]
separation/Hill radius as/rH:0.012 [*E]
orbital period Ps: 1.2067 ± 0.0008 d [B23r]
eccentricity es: ?
normalized ang. mom. αL: ?

other data, system (combined):
absolute mag. H: 12.25 [MPC]
slope parameter G: (0.15) [*A]
effective diameter dE: 10.54 ± 0.09 km [M**]
geometric albedo: 0.225 ± 0.033 [M**]
color index U-B: ?
color index B-V: ?
taxonomic type: ?
mass m: ?
density ρ: (1.6 g/cm3) [*A]
Hill radius rH: 2000 km [*E]

other data, primary:
diameter dp: 10.15 ± 0.09 km [*D]
rotation period RPp: 2.6703 ± 0.0003 h [B23r]
amplitude in mag., rotational ΔM: 0.16 [B23r]
amplitude in mag., mutual events ΔM:0.08 [B23r]
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: >2.84 km [*D]
diameter ratio ds/dp: >0.28 [B23r]
component mag. difference ΔM: <2.8 [*D]
rotation period RPs: ?

-- (11549) 1992 YY --discovery and notes:

Primary discovered 1992 Dec 25 from JCPM Yakiimo Station, Shimizu, Shizuoka, Japan by A. Natori and T. Urata. Alternate designation(s): 1959 UM. Linked to prediscovery observations from 1959 Oct 29. Permanent number assigned 1999 Sep 28.

Companion discovered 2023 Sep 07 by V. Benishek, P. Pravec, R. Durkee, M. Husarik, and G. Cervak using lightcurve observations from Sopot Observatory, Serbia; Shed of Science South Observatory, Pontotoc, Texas, USA; Skalnate Pleso Observatory, Slovakia. Announced 2023 Oct 27 [B23r].

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--Links to ADS abstracts:


© 2023 by Wm. Robert Johnston.
Last modified 28 October 2023.
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