Slipher is member of the mid-sized Padua family (507), an asteroid family named after 363 Padua and at least 25 million years old. It consists of mostly X-type asteroids, that were previously associated to 110 Lydia (the Padua family is therefore also known as Lydia family).[3][13][14]: 23
Slipher orbits the Sun in the central main-belt at a distance of 2.5–3.0 AU once every 4 years and 7 months (1,665 days). Its orbit has an eccentricity of 0.09 and an inclination of 5° with respect to the ecliptic.[1]
The body's observation arc begins with its first identification as 1953 UR at the discovering Goethe Link observatory in October 1953, or 9 years prior to its official discovery observation.[12]
In 2012, two rotational lightcurves of Slipher were obtained from photometric observations by astronomers at the Palomar Transient Factory in California. Lightcurve analysis gave a rotation period of 7.677 and 7.693 hours with a brightness variation of 0.20 and 0.19 magnitude in the S- and R-band, respectively (U=2/2).[10]
The Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a diameter of 20.21 kilometers based on an absolute magnitude of 12.2.[8]
Naming
This minor planet was named after the brothers Vesto Slipher (1876–1969) and Earl C. Slipher (1883–1964), both graduates of Indiana University. Vesto Slipher was a pioneer investigator of the spectra of the planets, and was the first to measure the redshifts of galaxies, which was instrumental for Hubble's discovery of the expanding Universe. Earl Slipher developed and improved the direct photography of the planets. His photographs are the only continuous and systematic record of the appearance of the planets for a period of more than half a century.[2]
^ abcdUsui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. (online, AcuA catalog p. 153)