9971 Ishihara
9971 Ishihara is a stony Flora asteroid from the inner regions of the asteroid belt, approximately in diameter. It was discovered by Japanese amateur astronomers Kin Endate and Kazuro Watanabe at Kitami Observatory on 16 April 1993, and named after Takahiro Ishihara, president of the astronomical society at Hiroshima.
Orbit and classification
Ishihara is a member of the Flora family, one of the largest families of stony asteroids in the asteroid belt. It orbits the Sun in the inner main-belt at a distance of 1.9–2.4 AU once every 3 years and 3 months. Its orbit has an eccentricity of 0.12 and an inclination of 3° with respect to the ecliptic. It was first identified as at Karl Schwarzschild Observatory in 1991, extending the body's observation arc by approximately 2 years prior to its official discovery at Kitami.Naming
This minor planet was named after Takahiro Ishihara, an observer of comets, communicator of astronomy, and former president of the astronomical society at Hiroshima. The was published by the Minor Planet Center on 6 January 2003.Physical characteristics
Rotation and poles
In January 2012, a rotational lightcurve of Ishihara was obtained from photometric observations by astronomers at the Palomar Transient Factory in California. Lightcurve analysis gave a rotation period of hours with a brightness amplitude of 1.06 in magnitude, which indicates that the body has a non-spheroidal shape.A 2016-published lightcurve, using modeled photometric data from the Lowell Photometric Database, gave a concurring period of 6.71574 hours, as well as a spin axis of in ecliptic coordinates.