1518 Rovaniemi, provisional designation 1938 UA, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 8 kilometers in diameter. Discovered by Yrjö Väisälä at the Turku Observatory in 1938, the asteroid was later named after the Finnish city of Rovaniemi.
The asteroid was first identified as 1928 TL at Simeiz Observatory on 7 October 1928.[a] The body's observation arc begins two weeks later at Simeiz on 21 October 1928, almost 10 years prior to the asteroid's official discovery observation at Turku.[11]
Orbit and classification
Rovaniemi is a member of the Flora family (402), a giant asteroid family and the largest family of stony asteroids in the main-belt.[3][4][12]: 23 It orbits the Sun in the inner main-belt at a distance of 1.9–2.5 AU once every 3 years and 4 months (1,212 days). Its orbit has an eccentricity of 0.14 and an inclination of 7° with respect to the ecliptic.[1]
In January 2009, two rotational lightcurves of Rovaniemi were obtained from photometric observations by René Roy at Blauvac Observatory (627) in France, and by Brian Warner at the Palmer Divide Observatory (716) in Colorado, United States. Lightcurve analysis gave a rotation period of 5.247 and 5.249 hours with a brightness amplitude of 0.26 and 0.25 magnitude, respectively (U=2+/3).[9][10]
Spin axis
In 2013, an international study modeled a lightcurve from various data sources including the Uppsala Asteroid Photometric Catalogue and the Palomar Transient Factory survey. The lightcurve gave a concurring period of 5.25047 hours and allowed for the determination of two spin axis of (62.0°, 60.0°) and (265.0°, 45.0°) in ecliptic coordinates (λ, β).[13]
The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.24 – derived from 8 Flora, the Flora family's largest member and namesake – and calculates a diameter of 8.98 kilometers based on an absolute magnitude of 12.4.[3]
^Alternatively to the Simeiz Observatory, it is also possible that observations at the Italian Turin Observatory on 13 and 14 October 1928, lead to the assignment of Rovaniemi's first provisional designation, 1928 TL.
^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.