4951 Iwamoto

It was discovered on 21 January 1990, by Japanese astronomers Yoshikane Mizuno and Toshimasa Furuta at Kani Observatory (403) in Japan.

[10] Iwamoto orbits the Sun in the inner main-belt at a distance of 1.9–2.6 AU once every 3 years and 5 months (1,239 days).

[6][5] The Collaborative Asteroid Lightcurve Link adopts Petr Pravec's revised WISE-data, that is, an albedo of 0.1844 and a diameter of 5.528 kilometers with on an absolute magnitude of 13.74.

[b] In May 2011, astronomers Etienne Morelle, Raoul Behrend obtained another lightcurve with a concurring period of 118 hours and an amplitude of 0.38 magnitude.(U=3).

Based on the secondary-to-primary mean-diameter ratio (Ds/Dp) of at least 0.76, it was estimated that Iwamoto and its moon measure 4.0 and 3.5 kilometers, respectively.