1503 Kuopio, provisional designation 1938 XD, is a stony Eunomian asteroid from the central region of the asteroid belt, approximately 19 kilometers in diameter. It was discovered on 15 December 1938, by astronomer Yrjö Väisälä at the Turku Observatory in Southwest Finland.[13] The asteroid was named for the Finnish town of Kuopio.[2]
Kuopio is a member of the Eunomia family (502), a prominent family of stony S-type asteroid and the largest one in the intermediate main belt with more than 5,000 members.[3][4][14]: 23 It orbits the Sun at a distance of 2.3–2.9 AU once every 4 years and 3 months (1,553 days). Its orbit has an eccentricity of 0.10 and an inclination of 12° with respect to the ecliptic.[1]
The body's observation arc begins with its first identification as 1935 EFatYerkes Observatory in March 1935, more than 3 years prior to its official discovery observation at Turku.[13]
Several rotational lightcurvesofKuopio were obtained from photometric observations since 2001. Analysis of these lightcurves gave a rotation period between 9.577 and 9.98 hours with a brightness variation of 0.01 to 0.05 magnitude (U=3/3/2/2/3).[8][11]
In 2011 and 2013, a modeled lightcurve using data from the Uppsala Asteroid Photometric Catalogue (UAPC) and other sources was published. In both studies, the modeled lightcurve gave a concurring period 9.9586 hours. The 2013-publication also determined two spin axis of (170.0°, −86.0°) and (27.0°, −61.0°) in ecliptic coordinates (λ, β) (U=n.a.).[9][10]
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, Kuopio measures between 18.43 and 22.99 kilometers in diameter and its surface has an albedo between 0.223 and 0.399.[5][6][7]
The Collaborative Asteroid Lightcurve Link derives an albedo of 0.3243 and a diameter of 18.54 kilometers based on an absolute magnitude of 10.5.[3]
^ 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)
^Schmadel, Lutz D. (2009). "Appendix – Publication Dates of the MPCs". Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008). Springer Berlin Heidelberg. p. 221. doi:10.1007/978-3-642-01965-4. ISBN978-3-642-01964-7.
