پیوند به بیرون[ویرایش]
2253 Espinette, provisional designation 1932 PB, is a stony asteroid and sizable Mars-crosser from the innermost regions of the asteroid belt, approximately 7 kilometers in diameter. Discovered by George Van Biesbroeck in 1932, the asteroid was named after the discoverer's residence "Espinette".
Espinette was discovered on 30 July 1932, by Belgian–American astronomer George Van Biesbroeck at the U.S. Yerkes Observatory, Wisconsin. The body was independently discovered on the following night by English-born South-African astronomer Cyril Jackson at Johannesburg, and by Soviet–Russian astronomer Grigory Neujmin at Simeiz Observatory on the Crimean peninsula, on August 4. No precoveries were taken. The asteroid's observation arc begins a few days after its official discovering observation.
Orbit and classification
The asteroid orbits the Sun in the inner main-belt at a distance of 1.6–2.9 AU once every 3 years and 5 months (1,260 days). Its orbit has an eccentricity of 0.28 and an inclination of 4° with respect to the ecliptic.
Several rotational lightcurves of Espinette have been obtained. In April 2011, photometric observations by American astronomer Brian A. Skiff rendered a well-defined rotation period of 7.442±0.002 hours with a brightness variation of 0.25 magnitude (U=3).[a]
In August 2015, another observation by Robert Stephens at the Center for Solar System Studies (U81), California, gave an identical period of 7.442±0.001 with an amplitude of 0.44 magnitude (U=3). Previous observations by Polish astronomer Wiesław Z. Wiśniewski in 1987, and by Italian Federico Manzini in 2005, rendered similar results (U=2/2).
Diameter and albedo
This minor planet was named "Espinette" after the discoverer's U.S. home in Williams Bay, Wisconsin, located near the discovering Yerkes Observatory. At their home, the Van Biesbroecks accommodated visitors of the observatory from all over the world. The name "Espinette" was proposed by the discoverer's children, and it refers to a coffeehouse in Belgium. The official naming citation was published by the Minor Planet Center on 1 June 1981 (M.P.C. 6059).