W Ursae Minoris
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Ursa Minor |
| Right ascension | 16h 08m 27.27s [1] |
| Declination | +86° 11′ 59.6″ |
| Apparent magnitude (V) | 8.51-9.59[2] |
| Characteristics | |
| Spectral type | A2V |
| Astrometry | |
| Radial velocity (Rv) | -12.8 ± 2 km/s |
| Proper motion (μ) | RA: −10.62 ± 0.68[3] mas/yr Dec.: 16.14 ± 0.73[3] mas/yr |
| Parallax (π) | 2.04 ± 0.64[3] mas |
| Distance | approx. 1,600 ly (approx. 500 pc) |
| Other designations | |
W Ursae Minoris is a multiple star system in the constellation Ursa Minor. Its apparent magnitude ranges from 8.51 to 9.59 over 1.7 days as one star passes in front of the other relative to observers on Earth.[2] The combined spectrum of the system is A2V, but the masses of the two component stars are unknown. A slight change in the orbital period in 1973 suggests there is a third component of the multiple star system—most likely a red dwarf—with an orbital period of 62.2 ± 3.9 years.[4]
References
- 1 2 "W Ursae Minoris - Eclipsing binary of Algol type (detached)". SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved 18 July 2015.
- 1 2 Watson, Christopher (4 January 2010). "W Ursae Minoris". AAVSO Website. American Association of Variable Star Observers. Retrieved 18 July 2015.
- 1 2 3 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357
- ↑ Kreiner, J. M.; Pribulla, T.; Tremko, J.; Stachowski, G. S.; Zakrzewski, B. (2008). "Period analysis of three close binary systems: TW And, TT Her and W UMi". Monthly Notices of the Royal Astronomical Society 383 (4): 1506–12. Bibcode:2008MNRAS.383.1506K. doi:10.1111/j.1365-2966.2007.12652.x.
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