_Savo.png) Shape ofSavo modelled from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | Y. Väisälä |
| Discovery site | Turku Obs. |
| Discovery date | 16 September 1938 |
| Designations | |
| (1494) Savo | |
Named after | Savonia[2] (Finnish region) |
| 1938 SJ · 1925 RL 1938 SG1 · 1948 VR 1951 SV · 1953 GD 1966 HB · 1976 HZ | |
| main-belt · (inner)[3] background[4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 78.50 yr (28,673 days) |
| Aphelion | 2.4777AU |
| Perihelion | 1.9019 AU |
| 2.1898 AU | |
| Eccentricity | 0.1315 |
| 3.24yr (1,184 days) | |
| 114.29° | |
| 0° 18m 14.76s / day | |
| Inclination | 2.4560° |
| 195.02° | |
| 184.32° | |
| Physical characteristics | |
| Dimensions | 7.80±0.22 km[5] 7.804±0.219 km[5] 9.23±0.43 km[6] 10.30 km(calculated)[3] |
| 5.35011±0.00028h[a] 5.35020±0.00005 h[7] 5.35031±0.00005 h[7] 5.35059±0.00001 h[8] 5.35059±0.00005 h[9] 5.35062±0.00005 h[7] | |
| 0.173±0.017[6] 0.20(assumed)[3] 0.349±0.061[5] | |
| SMASS = Sa[1] · S[3] | |
| 12.08±0.24[10] · 12.30[1][3][5] · 12.70[6] | |
1494 Savo, provisional designation1938 SJ, is a stony backgroundasteroid from the inner region of theasteroid belt, approximately 8 kilometers in diameter. Discovered by astronomerYrjö Väisälä at theTurku Observatory in 1938, the asteroid was later named after the Finnish region ofSavonia.[2]
Savo was discovered on 16 September 1938, by Finnish astronomerYrjö Väisälä at theIso-Heikkilä Observatory near Turku, Finland.[11] Two nights later, it was independently discovered by German astronomerArno Arthur Wachmann at theBergedorf Observatory in Hamburg.[2] However, theMinor Planet Center only acknowledges the first discoverer. The asteroid was first identified as1925 RL at the CrimeanSimeiz Observatory in September 1929, or nine years before its official discovery observation.[11]
Savo is an asteroid of the main belt'sbackground population that does not belong to any knownasteroid family.[4] It orbits the Sun in theinner asteroid belt at a distance of 1.9–2.5 AU once every 3 years and 3 months (1,184 days). Its orbit has aneccentricity of 0.13 and aninclination of 2° with respect to theecliptic.[1] The body'sobservation arc begins with its official discovery observation at Turku in September 1938.[11]
In theSMASS classification,Savo is an Sa-subtype that transitions from the stonyS-type to theA-type asteroids.[1]
In August 2006, a rotationallightcurve ofSavo was obtained from photometric observations by Czech astronomerPetr Pravec atOndřejov Observatory. Lightcurve analysis gave a well-definedrotation period of 5.35011 hours with a brightness amplitude of 0.52magnitude (U=3), indicative for a non-spherical shape.[a] Follow up observations at the Calvin College Observatory (H62) in 2007 and 2008, gave three nearly identical periods of 5.35020, 5.35031 and 5.35062 hours with an amplitude between 0.44 and 0.63 (U=3/3/3-).[7]
The asteroid's lightcurve has also been modeled twice. In 2011, the first modelling used photometric data from the AstDyS database and the Uppsala Asteroid Photometric Catalogue, and found two spin axis of (248.0°, −68.0°) and (83.0°, −66.0°) inecliptic coordinates (λ, β).[9] A refined modeling in 2016, using theLowell Photometric Database gave two poles of (50.0°, −65.0°) and (233.0°, −68.0°) in ecliptic coordinates.[8] Also, both studies found a concurring period of 5.35059 hours.[9][8]
According to the surveys carried out by the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Savo measures between 7.80 and 9.23 kilometers in diameter and its surface has analbedo between 0.173 and 0.349.[5][6] TheCollaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 10.30 kilometers based on anabsolute magnitude of 12.3.[3]
Thisminor planet was named after Finnish historical province ofSavonia.[2] The officialnaming citation was published by theMinor Planet Center in January 1956 (M.P.C. 1350).[12]
