Discovered by Y. Väisälä MPC designation 1696 Nurmela Discovered 18 March 1939 Discoverer Yrjö Väisälä Discovery site Iso-Heikkilä Observatory | Discovery date 18 March 1939 Minor planet category main-belt · Baptistina Orbits Sun Asteroid family Baptistina family Asteroid group Asteroid belt | |
Named after Tauno Nurmela
(University of Turku) Alternative names 1939 FF · 1939 GL
1949 DK · 1951 YK Similar 1450 Raimonda, Sun, 298 Baptistina, 12999 Toruń | ||
1696 Nurmela, provisional designation 1939 FF, is a carbonaceous Baptistina asteroid from the inner regions of the asteroid belt, approximately 10 kilometers in diameter. It was discovered on 18 March 1939, by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland.
Nurmela is a C-type asteroid and is the second-largest member of the small Baptistina family, which is named after 298 Baptistina, its largest member and namesake. It orbits the Sun at a distance of 2.0–2.5 AU once every 3 years and 5 months (1,242 days). Its orbit has an eccentricity of 0.10 and an inclination of 6° with respect to the ecliptic.
In March and April 2007, two rotational light-curves of Nurmela was obtained from photometric observations by Adrián Galád and Robert Stephens. They gave an identical rotation period of 3.1587 hours with a brightness variation of 0.33 and 0.42 magnitude, respectively (U=3/3).
According to the surveys carried out by the Japanese Akari satellite and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Nurmela measures between 9.23 and 10.31 kilometers in diameter, and its surface has an albedo between 0.116 and 0.155. The Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a diameter of 13.98 kilometers.
The minor planet was named in honor of Finnish academician Tauno Nurmela (1907–1985), some time professor of Romanic philology and later chancellor of University of Turku. Naming citation was published on 1 April 1980 (M.P.C. 5281).