1695 Walbeck, provisional designation 1941 UO, is a carbonaceous asteroid from the central region of the asteroid belt, approximately 19 kilometers in diameter. It was discovered on 15 October 1941, by Finnish astronomer Liisi Oterma at Turku Observatory in Southwest Finland, and named after Henrik Walbeck.[2][12]
Classification and orbit
The asteroid orbits the Sun in the central main-belt at a distance of 2.0–3.6 AU once every 4 years and 8 months (1,694 days). Its orbit has an eccentricity of 0.29 and an inclination of 17° with respect to the ecliptic.[1]Walbeck's observation arc begins the night after its official discovery observation.[12]
Physical characteristics
In the SMASS taxonomy, the carbonaceous asteroid is characterized as a Cg-type, an intermediate between the C-type and G-type asteroids.[1]
Lightcurves
In November 2006, a rotational lightcurve of Walbeck was obtained from photometric observations by French amateur astronomer Pierre Antonini. It gave a rotation period of 5.1607 hours with a brightness variation of 0.22 magnitude (U=3).[9] Two similar periods were obtained by David Romeuf and by a team of Hungarian astronomers (U=2/2).[9][10]
Diameter and albedo
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Walbeck measures between 17.88 and 19.62 kilometers in diameter and its surface has an albedo between 0.037 and 0.051.[4][5][7][8] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.046 and a diameter of 19.60 kilometers based on an absolute magnitude of 12.5.[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)
