Discovered by J. Comas Solà MPC designation 925 Alphonsina Minor planet category main-belt · (outer) Orbits Sun Discoverer Josep Comas i Solà Asteroid group Asteroid belt | Discovery date 13 January 1920 Alternative names 1920 GM · A902 ED Discovered 13 January 1920 Spectral type S-type asteroid Discovery site Fabra Observatory | |
Named after Alfonso X and Alfonso XIII
(King of Castile/Spain) Similar 276 Adelheid, 516 Amherstia, 193 Ambrosia, 849 Ara, 441 Bathilde | ||
925 Alphonsina, provisional designation 1920 GM, is a large, stony asteroid from the outer region of the asteroid belt, about 58 kilometers in diameter. It was discovered by Spanish astronomer of Catalan origin, Josep Comas i Solà, at the Fabra Observatory in Barcelona, on 13 January 1920.
The S-type asteroid orbits the Sun at a distance of 2.5–2.9 AU once every 4 years and 5 months (1,622 days). Its orbit is tilted by 21 degrees to the plane of the ecliptic and shows an eccentricity of 0.08. A large number of photometric light-curve analysis rendered a well-defined, concurring rotation period of 7.9 hours for the body.
According to the surveys carried out by the Infrared Astronomical Satellite, IRAS, the Japanese Akari satellite, and the Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, the asteroid's albedo is in the range of 0.20–0.28. In addition, the body's albedo has been inferred by using the technique of stellar occultation in 2003. The measurement also gave a diameter of 59.2 kilometers.
The minor planet was named in honor of the Iberian Kings, Alfonso X (1221–1284) and Alfonso XIII (1886–1941), King of Castile and Spain, respectively. The original citation mentions, that the 13th century king inspired the field of astronomy in the Middle Ages, and, that the latter king was a great enthusiast of the scientific development in Spain. It also mentions that the King of Spain approved the naming of the asteroid.