_Hopmann.png) Shape ofHopmann modeled from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 13 January 1929 |
| Designations | |
| (1985) Hopmann | |
Named after | Josef Hopmann (German astronomer)[2] |
| 1929 AE · 1951 CA2 1951 CP · 1952 KE 1964 PJ · 1973 AA4 | |
| main-belt · (outer)[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 88.16 yr (32,201 days) |
| Aphelion | 3.6021AU |
| Perihelion | 2.6408 AU |
| 3.1214 AU | |
| Eccentricity | 0.1540 |
| 5.51yr (2,014 days) | |
| 334.27° | |
| 0° 10m 43.32s / day | |
| Inclination | 17.159° |
| 305.15° | |
| 234.25° | |
| Physical characteristics | |
| 35.47 km(derived)[3] 35.51±3.1 km(IRAS:6)[1] 44.33±3.53 km[4] | |
| 17.476±0.003 h[5] 17.478±0.004 h[6] 17.4787±0.0001 h[7] 17.480±0.002 h[8] | |
| 0.039±0.007(IRAS:6)[4] 0.0613(derived)[3] | |
| C[3] | |
| 10.75±0.19[9] · 10.9[1][3] · 10.91[4] | |
1985 Hopmann (prov. designation:1929 AE) is a darkbackground asteroid in the outer regions of theasteroid belt. It was discovered on 13 January 1929, by astronomerKarl Reinmuth atLandessternwarte Heidelberg-Königstuhl in southern Germany.[10] The asteroid has arotation period of 17.5 hours and measures approximately 36 kilometers (22 miles) in diameter. It was later named after German astronomerJosef Hopmann (1890–1975).[2]
Hopmann is a darkC-type asteroid that orbits the Sun in theouter main-belt at a distance of 2.6–3.6 AU once every 5 years and 6 months (2,014 days). Its orbit has aneccentricity of 0.15 and aninclination of 17° with respect to theecliptic.[1] The first observation used for the body'sobservation arc was taken at the discovering observatory on 4 February 1926, or 22 days after its official discovering observation.[10]
Thisminor planet was named in memory of German astronomerJosef Hopmann (1890–1975), a director ofVienna Observatory between 1951 and 1962, a productive observer ofvariable andbinary stars, and a participant in the international program to observe near-Earth asteroid433 Eros in the early 1930s. The lunar craterHopmann is also named in his honour.[2] The officialnaming citation was published by theMinor Planet Center on 15 October 1977 (M.P.C. 4237).[11]
According to the survey carried out by the Infrared Astronomical SatelliteIRAS,Hopmann measures 35.51 kilometers in diameter.[1] TheCollaborative Asteroid Lightcurve Link agrees with the Supplemental IRAS Minor Planet Survey (SIMPS) data and derives analbedo of 0.039 and a diameter of 35.47 kilometers,[3] while observations with NASA'sWide-field Infrared Survey Explorer and its subsequentNEOWISE mission gave an albedo of 0.06 and a diameter of 44.33 kilometers.[4]
In January and February 2012, three rotationallightcurves were obtained byRobert Stephens at Santana Observatory (646), California, Josep Maria Aymami at Carmelita Observatory (B20), Barcelona, and Patricia Moravec at Oakley Southern Sky Observatory (E09), Australia. The lightcurves gave a well-definedrotation period of 17.476, 17.478 and 17.480 hours, respectively, with a brightness variation between 0.36 and 0.44magnitude (U=3/3/3-).[5][6][8] In 2016, a re-modeled lightcurve, constructed from data compiled in the Lowell Photometric Database, also gave a concurring period.[7]
