| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 11 September 1923 |
| Designations | |
| (1628) Strobel | |
Named after | Willi Strobel(astronomer)[2] |
| 1923 OG · 1926 GY 1947 GC · 1949 QA2 1952 DV2 · 1957 CA 1960 WH | |
| main-belt · (outer)[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 93.11 yr (34,007 days) |
| Aphelion | 3.2152AU |
| Perihelion | 2.8088 AU |
| 3.0120 AU | |
| Eccentricity | 0.0675 |
| 5.23yr (1,909 days) | |
| 244.38° | |
| 0° 11m 18.6s / day | |
| Inclination | 19.387° |
| 181.19° | |
| 289.14° | |
| Physical characteristics | |
| Dimensions | 51.15±14.91 km[4] 53.147±0.793 km[5] 54.26±16.39 km[6] 56.58±0.68 km[7] 57.06 km(derived)[3] 57.12±1.7 km(IRAS:12)[8] 59.345±0.484 km[9] |
| 9.52±0.01h[10] 11.80 h[11] | |
| 0.047±0.010[9] 0.05±0.03[6] 0.0504(derived)[3] 0.0532±0.003(IRAS:12)[8] 0.055±0.002[7] 0.0581±0.0113[5] 0.06±0.04[4] | |
| P[5] · X[12] · C[3] B–V = 0.840[1] U–B = 0.320[1] | |
| 10.02[1][6][7][8] · 10.08[3][5][11] · 10.31±0.20[12] · 10.32[4] | |
1628 Strobel (provisional designation1923 OG) is a carbonaceousasteroid from the outer region of theasteroid belt, approximately 55 kilometers in diameter.
It was discovered on 11 September 1923, by German astronomerKarl Reinmuth atHeidelberg Observatory in southern Germany, and named afterARI-astronomerWilli Strobel.[2][13]
Strobel orbits the Sun in theouter main-belt at a distance of 2.8–3.2 AU once every 5 years and 3 months (1,909 days). Its orbit has aneccentricity of 0.07 and aninclination of 19° with respect to theecliptic.[1] Strobel'sobservation arc begins two nights after its official discovery observation at Heidelberg in 1923.[13]
Strobel is a carbonaceousC-type asteroid. It is also classified as aP-type byWISE and as anX-type asteroid byPan-STARRS.[5][12]
American astronomerRichard Binzel obtained the first rotationallightcurve of Strobel in May 1984. It gave arotation period of 11.80 hours with a brightness amplitude of 0.22magnitude (U=2).[11] In May 2005, photometric observations by French amateur astronomerLaurent Bernasconi gave a shorter period of 9.52 hours and a brightness change of 0.20 magnitude (U=2).[10]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequentNEOWISE mission, Strobel measures between 51.15 and 59.35 kilometers in diameter, and its surface has analbedo between 0.047 and 0.06.[4][5][6][7][8][9] TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.0504 and a diameter of 57.06 kilometers with anabsolute magnitude of 10.08.[3]
Thisminor planet was named in honor of Willi Strobel (1909–1988), staff member atAstronomisches Rechen-Institut (ARI) since 1938, and author of the 1963-edition ofIdentifizierungsnachweis der Kleinen Planeten (Minor planet identifications, published by ARI).[2] The officialnaming citation was published by theMinor Planet Center on 20 February 1976 (M.P.C. 3931).[14]
