W Ursae Minoris
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]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Ursa Minor |
| Right ascension | 16h 08m 27.2728s[1] |
| Declination | +86° 11′ 59.5511″[1] |
| Apparent magnitude (V) | 8.51-9.59[2] |
| Characteristics | |
| Spectral type | A2V |
| Variable type | Eclipsing[2] |
| Astrometry | |
| Radial velocity (Rv) | −12.8 ± 2 km/s |
| Proper motion (μ) | RA: −12.128±0.057[1] mas/yr Dec.: 15.934±0.058[1] mas/yr |
| Parallax (π) | 2.4144 ± 0.0315[1] mas |
| Distance | 1,350 ± 20 ly (414 ± 5 pc) |
| Other designations | |
| Database references | |
| SIMBAD | data |
References
- Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- Watson, Christopher (4 January 2010). "W Ursae Minoris". AAVSO Website. American Association of Variable Star Observers. Retrieved 18 July 2015.
- "W UMi". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-10-07.
- 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.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.