Asteroids with Satellites Database--Johnston's Archive

(7088) Ishtar

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: NEA, Amor


orbital data, primary (osculating elements) [JPL] :
semimajor axis a: 1.980767174 AU
orbital period P: 2.787779032 yr
(= 1018.2362910 d)
eccentricity e: 0.390732639
perihelion distance q: 1.20681679 AU
aphelion distance Q: 2.754717558 AU
inclination i: 8.3009094°
argument of perihelion ω: 354.708970°
ascending node Ω: 102.686712°
mean anomaly M: 8.4718128°
perihelion passage TP: 2014 Apr 29.03803
Epoch: 2014 May 23
data arc: 1981-2013 (423 obs.)
Earth MOID: 0.223538 AU
Jupiter Tisserand invariant TJ: 3.751


orbital data, secondary:
binary dynamical type:A [P07f]
semimajor axis as: 2.8 km [*E]
separation/primary radius as/rp:4.0 [*E]
separation/Hill radius as/rH:0.021 [*E]
orbital period Ps: 0.8604 ± 0.0008 d [R06c]
eccentricity es: ?
normalized ang. mom. αL: 1.21 [P07f]

other data, system (combined):
absolute mag. H: 16.7 [MPC]
slope parameter G: (0.15) [*A]
effective diameter dE: 1.51 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: 130 km [*E]

other data, primary:
diameter dp: 1.39 km [*E]
rotation period RPp: 2.679 ± 0.000 h [R06c]
amplitude in mag., rotational ΔM: 0.11 [P09d]
pole direction Β, λ: ? , ?


other data, secondary:
diameter ds: 0.58 km [*E]
diameter ratio ds/dp: 0.42 ± 0.02 [R06c]
component mag. difference ΔM: 1.9 ± 0.1 [*D]
rotation period RPs: ?

-- (7088) Ishtar --discovery and notes:

Primary discovered 1992 Jan 01 from Palomar Observatory, California, USA by C. S. Shoemaker and E. M. Shoemaker. Alternate designation(s): 1992 AA . Linked to prediscovery observations from 1981 Mar 03. Permanent number assigned 1996 Jul 30.

Named 1997 Apr 22 for the mythological Mesopotamian goddess [MPC29671].

Companion discovered 2005 Dec 04 by V. Reddy, R. Dyvig, P. Pravec, P. Kusnirak, S. Gajdos, A. Galad, and L. Kornos using lightcurve observations from University of North Dakota, Grand Forks, North Dakota, USA; Ondrejov Observatory, Czech Republic; Modra Observatory, Slovakia. Announced 2006 Jan 31 [R06c].

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:


© 2006-2008, 2014 by Wm. Robert Johnston.
Last modified 21 September 2014.
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