1054 Forsytia/fɔːrˈsɪtiə/ is a dark background asteroid, approximately 46 kilometers in diameter, from the outer regions of the asteroid belt. It was discovered on 20 November 1925, by astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in southwest Germany and assigned provisional designation 1925 WD.[14] It is named after the flowering plant forsythia, and marks the beginning of a sequence of 28 thematically named asteroids by the discoverer.[3]
Orbit and classification
Forsytia is a non-family asteroid from the main belt's background population.[5] It orbits the Sun in the outer asteroid belt at a distance of 2.5–3.3 AU once every 5.00 years (1,826 days; semi-major axis of 2.92 AU). Its orbit has an eccentricity of 0.14 and an inclination of 11° with respect to the ecliptic.[1] The asteroid was first observed as A907 EA at Heidelberg in March 1907. The body's observation arc begins with its official discovery observation in November 1925.[14]
Due to his many discoveries, Karl Reinmuth submitted a large list of 66 newly named asteroids in the early 1930s. The list covered his discoveries with numbers between (1009) and (1200). This list also contained a sequence of 28 asteroids, starting with this asteroid, that were all named after plants, in particular flowering plants(also see list of minor planets named after animals and plants).[3]
In March 2002, a rotational lightcurve of Forsytia was obtained from photometric observations by American amateur astronomer John Gross at his Sonoran Skies Observatory (G94) in Arizona. Lightcurve analysis gave a well-defined rotation period of 7.650 hours with a brightness amplitude of 0.23 magnitude (U=3).[12]
Diameter and albedo
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Forsytia measures between 42.867 and 53.04 kilometers in diameter and its surface has an albedo between 0.035 and 0.0750.[6][7][8][9][10][11] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0592 and a diameter of 45.42 kilometers based on an absolute magnitude of 10.4.[4]
^ abcdMasiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Nugent, C.; et al. (November 2012). "Preliminary Analysis of WISE/NEOWISE 3-Band Cryogenic and Post-cryogenic Observations of Main Belt Asteroids". The Astrophysical Journal Letters. 759 (1): 5. arXiv:1209.5794. Bibcode:2012ApJ...759L...8M. doi:10.1088/2041-8205/759/1/L8.