_Turku.png) Shape ofTurku modelled from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | Y. Väisälä |
| Discovery site | Turku Obs. |
| Discovery date | 22 September 1938 |
| Designations | |
| (1496) Turku | |
Named after | Turku[2](Finnish city) |
| 1938 SA1 · 1928 QN 1928 RE · 1950 EC 1954 MH · 1957 HB | |
| main-belt · (inner) Flora[3] · background[4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 88.02 yr (32,148 days) |
| Aphelion | 2.5631AU |
| Perihelion | 1.8490 AU |
| 2.2060 AU | |
| Eccentricity | 0.1619 |
| 3.28yr (1,197 days) | |
| 90.547° | |
| 0° 18m 2.88s / day | |
| Inclination | 2.5005° |
| 294.38° | |
| 0.9272° | |
| Physical characteristics | |
| Dimensions | 7.47±0.31 km[5] 7.758±0.072 km[6] 7.973±0.018 km[7] 8.19 km(calculated)[3] |
| 6.47±0.01h[8] 6.47375±0.00001 h[9] | |
| 0.1930±0.0196[7] 0.203±0.024[6] 0.24(assumed)[3] 0.347±0.043[5] | |
| S(assumed)[3] | |
| 12.40[5] · 12.42±0.25[10] · 12.6[1][3] · 12.9[7] | |
1496 Turku, provisional designation1938 SA1, is a Florianasteroid from the inner regions of theasteroid belt, approximately 8 kilometers in diameter. It was discovered on 22 September 1938, by astronomerYrjö Väisälä at theIso-Heikkilä Observatory in Turku, Finland.[11] The asteroid was named for the Finnish city ofTurku.[2]
Turku is a member of theFlora family (402), a giantasteroid family and the largest family of stony asteroids in the main belt.[3] It is, however, a non-family asteroid from the main belt'sbackground population when applying the Hierarchical Clustering Method to its proper orbital elements.[4]
It orbits the Sun in theinner main-belt at a distance of 1.8–2.6 AU once every 3 years and 3 months (1,197 days). Its orbit has aneccentricity of 0.16 and aninclination of 3° with respect to theecliptic.[1] The body'sobservation arc begins with its first identification as1928 QN atJohannesburg Observatory in August 1928, more than 10 years prior to its official discovery observation at Turku.[11]
Turku is an assumedS-type asteroid, which is also the Flora family's overallspectral type.[3]
In April 2006, a rotationallightcurve ofTurku was obtained from photometric observations by French amateur astronomerLaurent Bernasconi. Lightcurve analysis gave arotation period of 6.47 hours with a brightness amplitude of 0.51magnitude, indicative of a non-spherical shape (U=3-).[8]
A 2016-published lightcurve, using modeled photometric data from the Lowell Photometric Database, gave a concurring period of 6.47375 hours, as well as a spin axis of (75.0°, −75.0°) inecliptic coordinates (λ, β).[9]
According to the survey carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Turku measures between 7.47 and 7.973 kilometers in diameter and its surface has analbedo between 0.1930 and 0.347.[5][6][7]
TheCollaborative Asteroid Lightcurve Link assumes an albedo of 0.24 – derived from8 Flora, the largest member and namesake of the Flora family – and calculates a diameter of 8.19 kilometers based on anabsolute magnitude of 12.6.[3]
Thisminor planet was named after Finnish city ofTurku, location of the discovering observatory and home of the discovererYrjö Väisälä. In ancient times, Turku was the capital of Finland.[2] The officialnaming citation was published by theMinor Planet Center in January 1956 (M.P.C. 1350).[12]
