|Discovered by M. F. Wolf|
MPC designation 1039 Sonneberga
Discovered 24 November 1924
Asteroid group Asteroid belt
|Discovery date 24 November 1924|
Minor planet category main-belt · (middle)
Absolute magnitude 11.1
Discoverer Max Wolf
|Named after Sonneberg
(German city and observatory)|
Alternative names 1924 TL · 1942 XG 1984 OK
Discovery site Landessternwarte Heidelberg-Königstuhl
Similar 528 Rezia, 417 Suevia, 540 Rosamunde, 509 Iolanda, 1056 Azalea
1039 Sonneberga, provisional designation 1924 TL, is a dark asteroid from the middle region of the asteroid belt, approximately 34 kilometers in diameter. It was discovered on 24 November 1924, by German astronomer Max Wolf at Heidelberg Observatory in southwest Germany.
The X-type asteroid is also classified as a very dark P-type asteroid. It orbits the Sun at a distance of 2.5–2.8 AU once every 4 years and 5 months (1,603 days). Its orbit has an eccentricity of 0.06 and an inclination of 5° with respect to the ecliptic. The body's observation arc begins with its official discovery observation, as no precoveries were taken, and no prior identifications were made.
In March 2005, a rotational lightcurve of Sonneberga was obtained by French amateur astronomer Laurent Bernasconi. Lightcurve analysis gave a longer-than average rotation period of 34.2 hours with a brightness variation of 0.41 magnitude (U=2).
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Sonneberga measures between 30.17 and 36.70 kilometers in diameter, and its surface has an albedo between 0.042 and 0.059. The Collaborative Asteroid Lightcurve Link derived an albedo of 0.033 and a diameter of 36.60 kilometers using an absolute magnitude of 11.5.
This minor planet was named for the city of Sonneberg, Thuringia in Germany and location of the Sonneberg Observatory. It was founded in 1925 by astronomer Cuno Hoffmeister after whom the minor planets 1726 Hoffmeister and 4183 Cuno are named. Naming citation was first mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 99).