| Discovery[1] | |
|---|---|
| Discovered by | P. Shajn |
| Discovery site | Simeiz Obs. |
| Discovery date | 15 August 1928 |
| Designations | |
| (1112) Polonia | |
| Pronunciation | /poʊˈloʊniə/[2] |
Named after | Poland (European country)[3] |
| 1928 PE · 1933 PA A908 XA | |
| main-belt[1][4] · (outer) Eos[5][6] | |
| Orbital characteristics[4] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 89.20yr (32,582 d) |
| Aphelion | 3.3423AU |
| Perihelion | 2.6963 AU |
| 3.0193 AU | |
| Eccentricity | 0.1070 |
| 5.25 yr (1,916 d) | |
| 326.70° | |
| 0° 11m 16.44s / day | |
| Inclination | 8.9911° |
| 302.86° | |
| 87.361° | |
| Physical characteristics | |
| 35.76±1.6 km[7] 37.55±0.60 km[8] 39.661±0.334 km[9] 47.058±0.368 km[10] | |
| 82.5±0.5 h[11][a] | |
| 0.0763±0.0097[10] 0.097±0.023[9] 0.128±0.005[8] 0.1319±0.012[7] | |
| S(Tholen)[4] L(SDSS-MOC)[12] B–V = 0.797[4] U–B = 0.447[4] | |
| 10.05[4][6][7][8][10] | |
1112 Polonia (provisional designation1928 PE) is anEoan asteroid from the outer regions of theasteroid belt, approximately 38 kilometers (24 miles) in diameter. Discovered by Soviet astronomerPelageya Shajn atSimeiz in 1928,[1] it was the first asteroid discovery made by a woman.[3] TheL-type asteroid has a longrotation period of 82.5 hours,[6] and was named for the country ofPoland.[3]
Polonia was first observed asA908 XA at the GermanHeidelberg Observatory in December 1908. It was officially discovered on 15 August 1928, by Soviet astronomerPelageya Shajn at theSimeiz Observatory on the Crimean peninsula.[1] On the following night at Simeis, it was independently discovered by her collegeGrigory Neujmin.[3] TheMinor Planet Center only recognized the first discoverer.[1]
Polonia was Shajn's first discovery; and the first asteroid discovery made by a woman,[3] bringing a long-standing tradition – which began with the discovery of1 Ceres in 1801 – of more than athousand minor planet discoveries exclusively made bymale astronomers, to an end.
Polonia is a core member of theEos family (606),[5][6] the largestasteroid family of theouter main belt consisting of nearly 10,000 asteroids.[13]
It orbits the Sun at a distance of 2.7–3.3 AU once every 5 years and 3 months (1,916 days;semi-major axis of 3.02 AU). Its orbit has aneccentricity of 0.11 and aninclination of 9° with respect to theecliptic.[4] The body'sobservation arc begins with its official discovery observation at Simeiz in 1928.[1]
In theTholen classification, Polonia is a common, stonyS-type asteroid.[4] In the more refinedSDSS-based taxonomy, it is characterized as an uncommonL-type,[12] which is similar to aK-type, the overallspectral type of the Eoan asteroids.[13]: 23
In October 2007, a rotationallightcurve of Polonia was obtained fromphotometric observations by American astronomerBrian Warner at hisPalmer Divide Observatory in Colorado. Lightcurve analysis gave a longrotation period of 82.5 hours with a brightness amplitude of 0.20magnitude (U=2).[6][11][a] The asteroid's long period is close to that of aslow rotator.
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer, Polonia measures between 35.76 and 47.058 kilometers in diameter and its surface has analbedo between 0.0763 and 0.1319.[7][8][9][10] TheCollaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is, an albedo of 0.1319 and a diameter of 35.76 kilometers based on anabsolute magnitude of 10.05.[6]
Thisminor planet was named "Polonia", theLatin name for the European country ofPoland. It is the first minor planet discovery made by a woman. The naming was proposed by L. Matkiewicz, an astronomer of Polish origin, who calculated the body's orbit. The official citation was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 104).[3]
