(4951) Iwamoto

compiled by Wm. Robert Johnston
last updated 28 November 2008

Orbital elements and other data (Assumed or derived values in parenthesis, my estimates in italics and parenthesis. Source identifications in brackets, see this link for sources):

orbital data, primary (osculating elements) [JPL]:
semimajor axis a: 2.2565565 AU
orbital period P: 3.39 y (=1,238.134 d)
eccentricity e: 0.1670162
perihelion distance q: 1.879675 AU
aphelion distance Q: 2.6334380 AU
inclination i: 7.52985°
argument of perihelion omega: 339.52195°
ascending node OMEGA: 101.12652°
mean anomaly M: 54.97431°
perihelion passage TP: 2006-10-02.929
Epoch: 10 APR 2007
data arc: 1931-2003 (223 obs.)

orbital data, secondary:
semimajor axis a: (30 km?)
semimajor axis/primary radius a/Rp: (15?)
orbital period P: 118.0 ± 0.2 h [I8836]
eccentricity e: ?

other data, primary:
diameter: 4 ± 0.8 km [I8836]
absolute magnitude H: 13.74 ± 0.06 [I8836]
rotation period: 118.0 ± 0.2 h [I8836]
amplitude delta M: 0.34 [I8836]
color index B-V: ?
color index V-R: ?
color index R-I: ?
slope parameter G: (0.15) assumed
geometric albedo: 0.20 ± 0.07 assumed [I8836]
mass: ?
density: ?
type: S [JPL]

other data, secondary:
diameter: 3.5 ± 0.7 km [I8836]
diameter ratio Ds/Dp: >=0.76 [I8836]
component magnitude difference: (0.6)
rotation period: 118.0 ± 0.2 h [I8836]

--(4951) Iwamoto--discovery and notes:

Primary discovered 21 January 1990 by Mizuno and Furuta at Kani. Alternate designations 1990 BM, 1931 UQ, 1985 QN6, 1985 RH5, and 1989 WS3.

Companion reported 11 May 2007 by V. Reddy, R. Dyvig, P. Pravec, P. Kusnirak, A. Galad, L. Kornos, S. Gajdos, J. Vilagi, D. Pray, W. Cooney, J. Gross, D. Terrell, Yu. Krugly, J. Ries, K. Archer, J. Oey, M. Pikler, M. Husarik, F. Colas, and A. Harris based on lightcurve observations from 25 December 2006 to 23 March 2007 from Badlands Observatory, Ondrejov Observatory, Modra Observatory, Carbuncle Hill Observatory, Sonoita Research Observatory, Kharkiv Observatory, McDonald Observatory, Ironwood Observatory, Leura Observatory, Skalnate Pleso Observatory, Shed of Science Observatory, and Pic du Midi Observatory.

--Links, more technical:

--Links, less technical:

--Links to ADS abstracts:

© 2007, 2008 by Wm. Robert Johnston.
Last modified 28 November 2008.
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