.png) Alightcurve-based 3D-model ofBohrmann | |
| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 7 March 1924 |
| Designations | |
| (1635) Bohrmann | |
Named after | Alfred Bohrmann (astronomer[2] |
| 1924 QW · 1931 VH1 1936 UJ · 1938 CH 1939 HL · 1943 EG1 1948 EA1 · 1953 FH | |
| main-belt · Koronis[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 93.24 yr (34,057 days) |
| Aphelion | 3.0174AU |
| Perihelion | 2.6894 AU |
| 2.8534 AU | |
| Eccentricity | 0.0575 |
| 4.82yr (1,761 days) | |
| 357.19° | |
| 0° 12m 16.2s / day | |
| Inclination | 1.8222° |
| 184.35° | |
| 136.06° | |
| Physical characteristics | |
| Dimensions | 16.60±0.82 km[4] 17.12 km(calculated)[3] 17.127±0.171[5] 17.533±0.244 km[6] 19.12±0.70 km[7] |
| 5.864±0.001 h[8] 5.86427±0.00005 h[9] 11.730±0.005 h[10] 11.73±0.01h[11] | |
| 0.187±0.015[7] 0.2104±0.0154[6] 0.219±0.049[5] 0.24(assumed)[3] 0.255±0.052[4] | |
| SMASS =S[1] · S[3] | |
| 10.95±0.01[8] · 11.0[1][3][4] · 11.05±0.24[12] · 11.1[6][7] | |
1635 Bohrmann, provisional designation1924 QW, is a stony Koronianasteroid from the outer region of theasteroid belt, approximately 17 kilometers in diameter. It was discovered on 7 March 1924, by German astronomerKarl Reinmuth atHeidelberg Observatory in southern Germany, and named for astronomerAlfred Bohrmann.[2][13]
The stonyS-type asteroid belongs to theKoronis family, a group consisting of few hundred known bodies with nearlyecliptical orbits. It orbits the Sun in theouter main-belt at a distance of 2.7–3.0 AU once every 4 years and 10 months (1,761 days). Its orbit has aneccentricity of 0.06 and aninclination of 2° with respect to the ecliptic.[1]
As noprecoveries were taken,Bohrmann'sobservation arc begins with the first used observation taken on the night following its discovery.[13]
According to the surveys carried out by the JapaneseAkari satellite and NASA'sWide-field Infrared Survey Explorer with its subsequentNEOWISE mission,Bohrmann measures between 16.6 and 19.1 kilometers in diameter, and its surface has analbedo between 0.187 and 0.255.[4][5][6][7] TheCollaborative Asteroid Lightcurve Link assumes a standard albedo for members of the Koronian family of 0.24, and calculates a diameter of 17.1 kilometers with anabsolute magnitude of 11.0.[3]
In September and October 2003, four rotationallightcurves were obtained for this asteroid from photometric observations at several observatories around the world, including the Whitin Observatory in Wellesley, Massachusetts, as well as by U.S. astronomersRobert Stephens andBrian Warner. The lightcurves gave two different solutions for theBohrmann'srotation period. One solution gave5.864±0.001[8] and5.86427±0.00005[9] hours, while the alternative solution gave11.73±0.01[11] and11.730±0.005[10] hours. The lightcurves had a concurring brightness variation of 0.25 inmagnitude (U=2/2/3/n.a.).[3]
Thisminor planet was named after German astronomerAlfred Bohrmann (1904–2000), a long-time observer of minor planets at the discovering Heidelberg Observatory and adiscoverer of minor planets himself. During his career he had published several hundreds of precise observations of asteroids.[2] The officialnaming citation was published by theMinor Planet Center on 20 February 1976 (M.P.C. 3931).[14]
