Discovered by A. Kopff MPC designation 647 Adelgunde Minor planet category main-belt · (inner) Absolute magnitude 11.41 Discoverer August Kopff | Discovery date 11 September 1907 Named after unknown Discovered 11 September 1907 Orbits Sun Asteroid group Asteroid belt | |
Alternative names 1907 AD · 1930 SA
1949 YJ · 1960 PA Discovery site Heidelberg-Königstuhl State Observatory Similar 276 Adelheid, 958 Asplinda, 847 Agnia, 193 Ambrosia, 516 Amherstia | ||
647 Adelgunde, provisional designation 1907 AD, is a stony asteroid from the inner regions of the asteroid belt, approximately 13 kilometers in diameter. It was discovered on 11 September 1907, by German astronomer August Kopff at Heidelberg Observatory in southern Germany.
The S-type asteroid is also classified as a X-type on the Tholen taxonomic scheme. It orbits the Sun at a distance of 2.0–2.9 AU once every 3 years and 10 months (1,393 days). Its orbit has an eccentricity of 0.19 and an inclination of 7° with respect to the ecliptic. As no precoveries were taken, Adelgunde's observation arc begins with its official discovery observation.
According to the space-based observations by NASA's Wide-field Infrared Survey Explorer and its subsequent NEOWISE mission, Adelgunde measures between 9.72 and 9.93 kilometers in diameter, and its surface has a high albedo of 0.488–0.514. Based on the survey carried out by the Japanese Akari satellite, it measures 13.7 kilometers with an albedo of 0.26. The Collaborative Asteroid Lightcurve Link agrees with the results obtained by AKARI, assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 15.5 kilometers, based on an absolute magnitude of 11.41. As the diameters are typically inferred from the body's absolute brightness and its reflectively, a higher albedo results in a smaller diameter.
In August 2006, a rotational light-curve of Adelgunde was obtained from photometric observations by astronomers Pierre Antonini and Antonio Vagnozzi. The light-curve gave a well-defined rotation period of 7001322020000000000♠32.202±0.007 hours with a brightness variation of 0.28 in magnitude (U=3).
The origin of the asteroid's name is unknown. It is speculated that the name comes from a list created in 1913 by the Astronomisches Rechen-Institut (ARI) containing suggestions of female names from history and mythology for the naming of minor planets. At the time, the naming process was not well developed and the ARI feared inconsistencies and potential confusion. The list was sent to several German astronomers, including Kopff, with the invitation to name all their discovered minor planets up to number 700.