250 Bettina
Main-belt asteroid
From Wikipedia, the free encyclopedia
250 Bettina is a large main belt asteroid that was discovered by Austrian astronomer Johann Palisa on September 3, 1885, in Vienna. It was named in honour of Baroness Bettina von Rothschild (née de Rothschild; 1858â1892), wife of Baron Albert von Rothschild who had bought the naming rights for £50.[5] Based upon the spectrum, it is classified as an M-type asteroid.
Lightcurve-base 3D-model of Bettina on the top with an image of the asteroid on the bottom. | |
| Discovery | |
|---|---|
| Discovered by | Johann Palisa |
| Discovery date | 3 September 1885 |
| Designations | |
| (250) Bettina | |
| Pronunciation | German: [bÉËtiËnaË][1] |
| A885 RA | |
| Main belt | |
| Orbital characteristics[2] | |
| Epoch 31 July 2016 (JD 2457600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 130.62 yr (47710 d) |
| Aphelion | 3.5657 AU (533.42 Gm) |
| Perihelion | 2.7325 AU (408.78 Gm) |
| 3.14906 AU (471.093 Gm) | |
| Eccentricity | 0.13229 |
| 5.59 yr (2041.1 d) | |
Average orbital speed | 16.78 km/s |
| 56.902° | |
| 0° 10m 34.932s / day | |
| Inclination | 12.819° |
| 23.862° | |
| 76.692° | |
| Physical characteristics | |
| Dimensions | 120.995±2.212 km[2] |
| Mass | (2.389 ± 1.157/0.547)Ã1018 kg[3] |
Mean density | 3.524 ± 1.707/0.806 g/cm3[3][a] |
| 5.0545 h (0.21060 d)[2] 5.055 h[4] | |
| 0.112±0.019[2] | |
| M | |
| 7.72[2] | |
In 1988, the asteroid was observed from the Collurania-Teramo Observatory, allowing a light curve to be produced that showed "an irregular behavior with a deeper minimum and a narrower maximum". The data showed a rotation period of 5.055 hours and a brightness variation of 0.17 ± 0.01 in magnitude. The ratio of the lengths of the major to minor axes for this asteroid were found to be 1.51 ± 0.03.[4]
Notes
- Assuming a diameter of 109 ± 5 km.
_mathilde.jpg){kind=small}