| Discovery[1] | |
|---|---|
| Discovered by | L. Kohoutek |
| Discovery site | Bergedorf Obs. |
| Discovery date | 26 October 1971 |
| Designations | |
| (2047) Smetana | |
| Pronunciation | /ˈsmɛtənə/[2] |
Named after | Bedřich Smetana (Czech composer)[3] |
| 1971 UA1 | |
| main-belt · (inner)[1] · Hungaria[1] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 44.77 yr (16,353 days) |
| Aphelion | 1.8783AU |
| Perihelion | 1.8658 AU |
| 1.8720 AU | |
| Eccentricity | 0.0033 |
| 2.56yr (936 days) | |
| 16.211° | |
| 0° 23m 5.28s / day | |
| Inclination | 25.281° |
| 36.611° | |
| 307.99° | |
| Knownsatellites | 1[4][5][6] |
| Physical characteristics | |
| Dimensions | 3.131±0.153 km[7] 3.85 km(calculated)[4] |
| 2.4801±0.0005h[8][a] 2.4969±0.0004 h[9][a] 2.4970±0.0003 h[6][a] 2.498±0.001 h[10] | |
| 0.3(assumed)[4] 0.544±0.069[7] | |
| E[4] | |
| 13.80[7] · 14.0[1][4] · 14.25±0.05[6] | |
2047 Smetana, provisional designation1971 UA1, is a bright Hungariaasteroid and synchronousbinary system from the innermost regions of theasteroid belt, approximately 3.5 kilometers in diameter. It was discovered on 26 October 1971, by Czech astronomerLuboš Kohoutek atBergedorf Observatory in Hamburg, Germany.[11] The asteroid was named after Czech composerBedřich Smetana.[3] Its sub-kilometer sizedminor-planet moon was discovered in 2012.
Smetana is a bright member of theHungaria family, which form the innermost dense concentration of asteroids in theSolar System. It orbits the Sun in theinner main-belt at a distance of 1.9–1.9 AU once every 2 years and 7 months (936 days). Its orbit has aneccentricity of 0.00 and aninclination of 25° with respect to theecliptic.[1] The asteroid'sobservation arc begins with its official discovery observation at Bergedorf, with noprecoveries taken, and no prior identifications made.[11]
Smetana is an assumedE-type asteroid.[4]
Between 2006 and 2012, several rotationallightcurves ofSmetana were obtained from photometric observations by American astronomerBrian Warner at his Palmer Divide Observatory (716) and CS3–Palmer Divide Station (U82) in Colorado and California, respectively. Lightcurve analysis gave arotation period between 2.4801 and 2.498 hours with a brightness variation of between 0.12 and 0.16magnitude (U=2+/2+/3/3).[6][8][9][10][a]
During Warner's photometric observations in 2012, it was revealed thatSmetana is a synchronousbinary asteroid with an orbitingminor-planet moon. The satellite orbits its primary every 22.43 hours and measures approximately 0.63 kilometers in diameter.[5][6] However the binary status ofSmetana has not yet been confirmed unambiguously, since observations in 2016 could not clearly detect any mutualoccultation and eclipsing events.[10]
According to the surveys carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Smetana measures 3.131 kilometers in diameter and its surface has analbedo of 0.544.[7] The Collaborative Asteroid Lightcurve Link assumes an albedo of 0.30 – a compromise value between 0.4 and 0.2, corresponding to the Hungaria asteroids both as family and orbital group – and calculates a diameter of 3.85 kilometers with anabsolute magnitude of 14.0.[4]
Thisminor planet was named for the Czech national composerBedřich Smetana (1824–1884), best known for the operaThe Bartered Bride, the cycle of six symphonic poemsMy homeland and the string quartetFrom my life.[3] The officialnaming citation was published by theMinor Planet Center on 1 July 1979 (M.P.C. 4786).[12]