| Discovery[1] | |
|---|---|
| Discovered by | Y. Väisälä |
| Discovery site | Turku Obs. |
| Discovery date | 12 September 1936 |
| Designations | |
| (1405) Sibelius | |
Named after | Jean Sibelius (Finnish composer)[2] |
| 1936 RE · 1951 CO 1953 VK3 · 1963 ST | |
| main-belt · Flora[3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 66.40 yr (24,254 days) |
| Aphelion | 2.5817AU |
| Perihelion | 1.9215 AU |
| 2.2516 AU | |
| Eccentricity | 0.1466 |
| 3.38yr (1,234 days) | |
| 312.34° | |
| 0° 17m 30.12s / day | |
| Inclination | 7.0301° |
| 312.08° | |
| 95.795° | |
| Physical characteristics | |
| Dimensions | 6.21±0.35 km[4] 6.810±0.098 km[5] 7.175±0.089 km[6] 7.20 km(taken)[3] 7.204 km[7] 9.26±1.95 km[8] 12.18±1.1 km[9] |
| 6.051±0.001h[a][b] | |
| 0.1432±0.029[9] 0.27±0.15[8] 0.3191[7] 0.3516±0.0646[6] 0.388±0.040[5] 0.458±0.068[4] | |
| S[3][10] | |
| 12.03(R)[a] · 12.3[9] · 12.48[6] · 12.5[1][4][8] · 12.57±0.078[3][7] · 12.57±0.33[10] | |
1405 Sibelius (provisional designation1936 RE) is a stony Florianasteroid from the inner regions of theasteroid belt, approximately 8 kilometers in diameter. It was discovered on 12 September 1936, by Finnish astronomerYrjö Väisälä atTurku Observatory in Southwest Finland.[11] The asteroid was named after composerJean Sibelius.[2]
Sibelius is a member of theFlora family, one of the largest populations of stony asteroids in the entire main-belt. It orbits the Sun in theinner main-belt at a distance of 1.9–2.6 AU once every 3 years and 5 months (1,234 days). Its orbit has aneccentricity of 0.15 and aninclination of 7° with respect to theecliptic.[1] The body'sobservation arc begins with an observation taken at Turku two weeks prior to its official discovery observation.[11]
Sibelius has been characterized as anS-type asteroid by thePan-STARRS photometric survey.[10]
In October 2007, a rotationallightcurve of Sibelius was obtained from photometric observations taken byPetr Pravec at theOndřejov Observatory in theCzech Republic. Lightcurve analysis gave arotation period of 6.051 hours with a brightness variation of 0.11magnitude (U=3-).[a][b]
According to the surveys carried out by theInfrared Astronomical Satellite (IRAS) and NASA'sWide-field Infrared Survey Explorer (WISE) with its subsequentNEOWISE mission, Sibelius measures between 6.21 and 12.18 kilometres (3.86 and 7.57 mi) in diameter and its surface has analbedo between 0.14 and 0.48.[4][5][6][8][9] TheCollaborative Asteroid Lightcurve Link adopts an albedo of 0.3191 and a diameter of 7.20 kilometres (4.47 mi) from Petr Pravec's revised WISE thermal observations.[3][7]
Thisminor planet was named forJean Sibelius (1865–1957), Finnish violinist and composer of the late Romantic and early-modern periods.[2] The officialnaming citation was published by theMinor Planet Center on 20 February 1976 (M.P.C. 3928).[12]
