Numerowia orbits the Sun in the outer main-belt at a distance of 2.7–3.0 AU once every 4 years and 10 months (1,771 days). Its orbit has an eccentricity of 0.05 and an inclination of 13° with respect to the ecliptic.[1] The asteroid's observation arc begins at Heidelberg four days after its official discovery observation.[9]
In February 2006, a rotational lightcurve of Numerowia was obtained from photometric observations by astronomer Lawrence Molnar and colleges at the Calvin–Rehoboth Observatory in New Mexico, United States. Lightcurve analysis gave a well-defined rotation period of 4.7743 hours with a high brightness variation of 0.63 magnitude (U=3), indicating that the body has a non-spheroidal shape.[7]
A 2016-published lightcurve, using modeled photometric data from the Lowell Photometric Database (LPD), gave a concurring period of 4.77529 hours (U=n.a.), as well as two spin axis of (64.0°, −50.0°) and (271.0°, −69.0°) in ecliptic coordinates (λ, β).[8]
According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Numerowia measures between 14.173 and 15.63 kilometers in diameter and its surface has an albedo between 0.141 and 0.168.[4][5][6]
The Collaborative Asteroid Lightcurve Link assumes a standard albedo for C-type asteroid of 0.057 and consequently calculates a larger diameter of 27.90 kilometers using an absolute magnitude of 11.5.[3]
This minor planet was named after Russian astronomer and geophysicist Boris Numerov (1891–1941), founder and director of the Institute for Theoretical Astronomy in Leningrad, who was executed for espionage by the Soviet Union in 1941. The accusation was based on the fact that a German had named the asteroid after him.[2] In 1957, his memory was rehabilitated.[10] The lunar crater Numerov was also named in his honour. The official naming citation was published by Paul HergetinThe Names of the Minor Planets in 1955 (H 112).[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)
