1159 Granada, provisional designation 1929 RD, is a dark background asteroid and relatively slow rotator from the inner regions of the asteroid belt, approximately 30 kilometers in diameter. It was discovered on 2 September 1929, by astronomer Karl Reinmuth at the Heidelberg Observatory in southwest Germany.[14] The asteroid was named for the Spanish city and province of Granada.[2]
Orbit and classification
Granada is a background asteroid that does not belong to any known asteroid family. It orbits the Sun in the inner main-belt at a distance of 2.2–2.5 AU once every 3 years and 8 months (1,341 days). Its orbit has an eccentricity of 0.06 and an inclination of 13° with respect to the ecliptic.[1] The body's observation arc begins nine days after its official discovery observation at Heidelberg.[14]
Physical characteristics
Although Granada is an assumed S-type asteroid,[3] it has a notably low albedo (see below) for an asteroid of the inner main-belt, even below that of most carbonaceous asteroids.
Slow rotation
In September 1984, a rotational lightcurve of Granada was obtained from photometric observations by astronomer Richard Binzel. Lightcurve analysis gave a rotation period of 31 hours with a brightness variation of 0.28 magnitude (U=2).[11] In October 2010, photometric observations in the R-band by astronomers at the Palomar Transient Factory gave a period of 72.852 hours and an amplitude of 0.24 (U=2).[12] While not being a slow rotator, Granada's period is significantly longer than the typical 2 to 20 hours measures for most asteroids.
^ 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)