1764 Cogshall
1764 Cogshall, provisional designation , is a carbonaceous Themistian asteroid from the outer regions of the asteroid belt, approximately 26 kilometers in diameter. It was discovered on 7 November 1953, by astronomers of the Indiana Asteroid Program at Goethe Link Observatory in Indiana, United States. The asteroid was named after Wilbur Cogshall, professor of astronomy at Indiana University. Orbit and classification. "Cogshall" is a Themistian asteroid that belongs to the Themis family (), a very large family of carbonaceous asteroids, named after 24 Themis. It orbits the Sun in the outer main-belt at a distance of 2.7–3.5 AU once  every 5 years and 5 months (1,987 days). Its orbit has an eccentricity of 0.12 and an inclination of 2° with respect to the ecliptic. The asteroid was first identified as at Johannesburg Observatory in June 1935. The body's observation arc begins with its identification as at Turku Observatory in February 1939, more than 14 years prior to its official discovery observation at Goethe Link. Physical characteristics. Rotation period. In May 2005, a rotational lightcurve of "Cogshall" was obtained from photometric observations by French amateur astronomer Pierre Antonini. Lightcurve analysis gave a well-defined rotation period of 3.62417  hours with a brightness variation of 0.21 magnitude (). Observations at the Palomar Transient Factory in 2012, gave a concurring period of 3.624 and 3.630 hours with an amplitude of 0.22 and 0.20 magnitude in the R- and S-band, respectively (). Diameter and albedo. According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, "Cogshall" measures between 25.14 and 29.671 kilometers in diameter and its surface has an albedo between 0.0606 and 0.109. The "Collaborative Asteroid Lightcurve Link" derives an albedo of 0.0712  and a diameter of 26.13 kilometers based on an absolute magnitude of 11.4. Naming. This minor planet was named after American astronomer Wilbur A. Cogshall, who was a professor of astronomy at Indiana University and director of the Kirkwood Observatory for more than four decades (1900–1944). His research included visual binary stars and the photography of solar eclipses. The name was proposed by Frank K. Edmondson, who initiated the Indiana Asteroid Program. The official was published by the Minor Planet Center on 20 February 1971 ().