| Discovery[1] | |
|---|---|
| Discovered by | Y. Väisälä |
| Discovery site | Turku Obs. |
| Discovery date | 4 March 1935 |
| Designations | |
| (1947) Iso-Heikkilä | |
Named after | Iso-Heikkilä(location)[2] |
| 1935 EA | |
| main-belt · (outer)[3] Eos[4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 81.94 yr (29,928 days) |
| Aphelion | 3.2712AU |
| Perihelion | 3.0367 AU |
| 3.1539 AU | |
| Eccentricity | 0.0372 |
| 5.60yr (2,046 days) | |
| 198.82° | |
| 0° 10m 33.6s / day | |
| Inclination | 11.912° |
| 90.908° | |
| 144.06° | |
| Physical characteristics | |
| Dimensions | 29.20 km(derived)[3] 30.72±0.86 km[5] 31.61±0.81 km[6] |
| 5.0158h[7] | |
| 0.049±0.009[6] 0.0571(derived)[3] 0.091±0.006[5] | |
| D[8] · C[3] | |
| 10.80[5] · 11.4[1][3][6] · 11.51[7] · 11.61±0.33[8] | |
1947 Iso-Heikkilä, provisional designation1935 EA, is a carbonaceous Eosasteroid from the outer region of theasteroid belt, approximately 30 kilometers in diameter. It was discovered on 4 March 1935, by Finnish astronomerYrjö Väisälä atTurku Observatory in Southwest Finland.[9] It was named after the location of the discovering observatory, which is also known as the "Iso-Heikkilä Observatory".[2]
Iso-Heikkilä is a member of theEos family (606), the largestasteroid family in theouter main belt consisting of nearly 10,000 asteroids.[4][10]: 23 It orbits the Sun in theouter main-belt at a distance of 3.0–3.3 AU once every 5 years and 7 months (2,046 days). Its orbit has aneccentricity of 0.04 and aninclination of 12° with respect to theecliptic.[1] As noprecoveries were taken, and no prior identifications were made, the body'sobservation arc begins with its discovery observation.[9]
TheC-type asteroid has been characterized as a rare and reddishD-type asteroid byPan-STARRS' large-scale photometric survey.[8]
According to the surveys carried out by the JapaneseAkari satellite and NASA'sWide-field Infrared Survey Explorer with its subsequentNEOWISE mission,Iso-Heikkilä measures 30.7 and 31.6 kilometers in diameter, and its surface has analbedo of 0.091 and 0.049, respectively.[5][6] TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.0571 and a diameter of 29.2 kilometers with anabsolute magnitude of 11.4.[3]
In October 2005, a rotationallightcurve ofIso-Heikkilä was obtained from photometric observations by Slovak astronomerAdrián Galád. It gave arotation period of 5.0158 hours with a brightness variation of 0.35 magnitude. However, the lightcurve is ambiguous and several alternative period solutions are possible (U=n.a.)[7]
Thisminor planet was named for the farm, which is located in theIso-Heikkilä district and owned by Turku University. It became the site of the Turku Observatory, which is also calledIso-Heikkilä Observatory (Finnish:Iso-Heikkilän tähtitorni). It was the observatory's first minor planet discovery.[2] The official naming citation was published by theMinor Planet Center on 1 August 1980 (M.P.C. 5450).[11]
