1179 Mally, provisional designation 1931 FD, is an asteroid and long-lost minor planet from the central region of the asteroid belt, approximately 13 kilometers in diameter. Discovered by Max Wolf in 1931, the asteroid was lost until its rediscovery in 1986. The discoverer named it after his daughter-in-law, Mally Wolf.
Mally orbits the Sun in the central main-belt at a distance of 2.2–3.1 AU once every 4 years and 3 months (1,548 days). Its orbit has an eccentricity of 0.17 and an inclination of 9° with respect to the ecliptic.[1] The body's observation arc begins with its official discovery observation at Heidelberg in 1931.[10]
Physical characteristics
Diameter and albedo
According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Mally measures between 11.20 and 16.60 kilometers in diameter, and its surface has an albedo between 0.059 and 0.097.[4][5][6][7][8]
The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.10 – a compromise value between the brighter stony (0.20) and darker carbonaceous asteroids (0.057) used for bodies with a semi-major axis between 2.6 and 2.7 AU – and calculates a diameter of 10.7 kilometers based on an absolute magnitude of 12.98.[3]
Rotation period
In September 2013, a rotational lightcurve of Mally was obtained from photometric observations taken at the Palomar Transient Factory in California. The fragmentary lightcurve gave a longer than average rotation period of 46.6 hours with a brightness variation of 0.08 magnitude.[9] However, the obtained result is poorly rated by CALL (U=1).[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)