WR 134
| Observation data Epoch 2000 Equinox 2000 | |
|---|---|
| Constellation | Cygnus |
| Right ascension | 20h 11m 14.193s[1] |
| Declination | 36° 10′ 35.07″[1] |
| Apparent magnitude (V) | 8.08[2] |
| Characteristics | |
| Evolutionary stage | Wolf-Rayet |
| Spectral type | WN6-s[3] |
| U−B color index | −0.44[2] |
| B−V color index | 0.00[2] |
| Astrometry | |
| Proper motion (μ) | RA: −4.66[1] mas/yr Dec.: −8.59[1] mas/yr |
| Parallax (π) | 0.04 ± 0.68[1] mas |
| Distance | 1,740[4] pc |
| Absolute magnitude (MV) | -5.07[3] |
| Details | |
| Mass | 19[3] M☉ |
| Radius | 5.29[3] R☉ |
| Luminosity | 400,000[3] L☉ |
| Temperature | 63,100[3] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
WR 134 is a variable Wolf-Rayet star located around 6,000 light years away from Earth in the constellation of Cygnus, surrounded by a faint bubble nebula blown by the intense radiation and fast wind from the star.
WR 134 is classified as an Algol type eclipsing variable and given the designation V1769 Cygni,[5] but the variation is not strictly periodic and brightness changes occur on timescales of hours to days. It has been investigated several times to search for companions. Morel reported a 2.25 day primary period but considered the variations to be due to rotational modulation rather than the effects of a companion.[6] Rustamov suggests a 1.887 day orbital period with a K-M dwarf companion, but with additional optical variations.[7]
Both hard and soft X-rays have been detected from WR 134 but the sources are not fully explained. The emissions do not match a single star of the expected temperature, are not sufficient for colliding winds between two hot stars, and any compact source such as a neutron star or cool dwarf would be in an unlikely orbit.[8]
References
- 1 2 3 4 5 Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
- 1 2 3 Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues 2237. Bibcode:2002yCat.2237....0D.
- 1 2 3 4 5 6 Hamann, W. -R.; Gräfener, G.; Liermann, A. (2006). "The Galactic WN stars". Astronomy and Astrophysics 457 (3): 1015. arXiv:astro-ph/0608078. Bibcode:2006A&A...457.1015H. doi:10.1051/0004-6361:20065052.
- ↑ Van Der Hucht, K. A. (2001). "The VIIth catalogue of galactic Wolf–Rayet stars". New Astronomy Reviews 45 (3): 135. Bibcode:2001NewAR..45..135V. doi:10.1016/S1387-6473(00)00112-3.
- ↑ Bibcode: 1971GCVS3.C......0K
- ↑ Morel, T.; Marchenko, S. V.; Eenens, P. R. J.; Moffat, A. F. J.; Koenigsberger, G.; Antokhin, I. I.; Eversberg, T.; Tovmassian, G. H.; Hill, G. M.; Cardona, O.; St‐Louis, N. (1999). "A 2.3 Day Periodic Variability in the Apparently Single Wolf‐Rayet Star WR 134: Collapsed Companion or Rotational Modulation?". The Astrophysical Journal 518: 428. Bibcode:1999ApJ...518..428M. doi:10.1086/307250.
- ↑ Rustamov, D. N.; Cherepashchuk, A. M. (2012). "Spectral and photometric studies of the Wolf-Rayet star WR 134 = HD 191765". Astronomy Reports 56 (10): 761. Bibcode:2012ARep...56..761R. doi:10.1134/S1063772912100058.
- ↑ Skinner, S. L.; Zhekov, S. A.; Güdel, M.; Schmutz, W.; Sokal, K. R. (2010). "X-Ray Emission from Nitrogen-Type Wolf-Rayet Stars". The Astronomical Journal 139 (3): 825. Bibcode:2010AJ....139..825S. doi:10.1088/0004-6256/139/3/825.
External links
http://apod.nasa.gov/apod/ap120621.html
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