Asteroids with Satellites Database--Johnston's Archive

(16635) 1993 QO

compiled by Wm. Robert Johnston
last updated 29 May 2019

--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: Mars crossing asteroid


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 2.2983160948 AU
orbital period P: 3.484292752 yr
(= 1272.6619636 d)
eccentricity e: 0.2842352769
perihelion distance q: 1.64505358 AU
aphelion distance Q: 2.951578606 AU
inclination i: 21.943081°
argument of perihelion ω: 77.948332°
ascending node Ω: 313.810362°
mean anomaly M: 4.711836°
perihelion passage TP: 2014 Nov 22.342847
Epoch: 2014 Dec 09
data arc: 1986-2014 (712 obs.)
Earth MOID: 0.782748 AU
Jupiter Tisserand invariant TJ: 3.446


orbital data, secondary:
binary dynamical type:A [M09a]
semimajor axis as: 7.9 km [*E]
separation/primary radius as/rp:5.4 [*E]
separation/Hill radius as/rH:0.021 [*E]
orbital period Ps: 1.344 ± 0.0012 d [P07c]
eccentricity es: ?
normalized ang. mom. αL: 1.24 [M09a]

other data, system (combined):
absolute mag. H: 14.2 [MPC]
14 ± 0.3 [P07c]
slope parameter G: (0.15) [*A]
effective diameter dE: 3.07 ± 0.53 km [*N16]
geometric albedo: 0.32 ± 0.11 [*N16]
color index U-B: ?
color index B-V: ?
taxonomic type: ?
mass m: ?
density ρ: (1.6 g/cm3) [*A]
Hill radius rH: 380 km [*E]

other data, primary:
diameter dp: 2.9 ± 0.5 km [*D]
rotation period RPp: 7.622 ± 0.002 h [P07c]
amplitude in mag., rotational ΔM: ?
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 1.02 km [*D]
diameter ratio ds/dp: 0.35 [P16d]
component mag. difference ΔM: 2.3 [*D]
rotation period RPs: 2.2083 ± 0.0002 h [P07c]

-- (16635) 1993 QO --discovery and notes:

Primary discovered 1993 Aug 20 from Palomar Observatory, California, USA by E. F. Helin. Alternate designation(s): 1986 QC. Linked to prediscovery observations from 1986 Aug 26. Permanent number assigned 2000 Sep 13.

Companion discovered 2007 Sep 02 by D. Pray, P. Pravec, P. Kusnirak, K. Hornoch, Yu. Krugly, V. Chiorny, M. Husarik, M. Pikler, J. Vilagi, S. Gajdos, A. Galad, W. Cooney, J. Gross, D. Terrell, N. Gaftonyuk, R. Stephens, R. Durkee, F. Marchis, M. Baek, B. Macomber, V. Reddy, F. Colas, J. Lecacheux, and J. Ries using lightcurve observations from Carbuncle Hill Observatory, Greene, Rhode Island, USA; Ondrejov Observatory, Czech Republic; Kharkiv National University, Ukraine; Skalnate Pleso Observatory; Modra Observatory, Slovakia; Sonoita Research Observatory, Sonoita, Arizona, USA; Simeiz Observatory; Goat Mountain Astronomical Research Station, Yucca Valley, CA; Minneapolis, MN; SETI Institute; University of California at Berkeley; University of North Dakota, Grand Forks; IMCCE and Pic du Midi Observatory; McDonald Observatory, Texas, USA. Announced 2007 Nov 19 [P07c].

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© 2007-2014, 2019 by Wm. Robert Johnston.
Last modified 29 May 2019.
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