S Persei
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Perseus |
| Right ascension | 2h 22m 51.70928s[1] |
| Declination | 58° 31′ 11.4476″[1] |
| Apparent magnitude (V) | 9.23[2] (7.9 - 12.0[3]) |
| Characteristics | |
| Spectral type | M4.5I[2] (M3-M6Ia[4]) |
| B−V color index | 2.65[2] |
| Variable type | SRc[3] |
| Astrometry | |
| Radial velocity (Rv) | -39.71[5] km/s |
| Proper motion (μ) | RA: -2.70[1] mas/yr Dec.: -0.29[1] mas/yr |
| Parallax (π) | 1.66 ± 1.81[1] mas |
| Distance | 7,890 ly (2,420[6] pc) |
| Absolute magnitude (MV) | -6.36[2] |
| Details | |
| Radius | 780-1,230[2] R☉ |
| Luminosity | 88,000 - 221,000[2] L☉ |
| Temperature | ~3,500[2] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
S Persei is a red supergiant or hypergiant[7] located in the Double Cluster in Perseus, north of the cluster NGC 869. It is a representative of the semiregular variables, whose periods of variation are subject to more irregularities than those of Mira variable red supergiants.
Many of the visually bright (5th - 7th magnitude) variable stars belong to this class of semiregulars, as these stars are extremely large and luminous, and hence visible across long distances. S Persei may be over 1,000 times the sun's radius (R☉), but the most likely value is 780 R☉.[2]
S Persei is surrounded by clouds containing water molecules which produce maser emission. This allows the distance to be measured very accurately using very long baseline interferometry.[6]
See also
References
- 1 2 3 4 5 Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
- 1 2 3 4 5 6 7 8 Emily M. Levesque; Philip Massey; K. A. G. Olsen; Bertrand Plez; et al. (August 2005). "The Effective Temperature Scale of Galactic Red Supergiants: Cool, but Not As Cool As We Thought". The Astrophysical Journal 628 (2): 973–985. arXiv:astro-ph/0504337. Bibcode:2005ApJ...628..973L. doi:10.1086/430901.
- 1 2 Samus', N. N.; Goranskii, V. P.; Durlevich, O. V.; Zharova, A. V.; Kazarovets, E. V.; Kireeva, N. N.; Pastukhova, E. N.; Williams, D. B.; Hazen, M. L. (2003). "An Electronic Version of the Second Volume of the General Catalogue of Variable Stars with Improved Coordinates". Astronomy Letters 29 (7): 468. Bibcode:2003AstL...29..468S. doi:10.1134/1.1589864.
- ↑ Richards, A. M. S.; Yates, J. A.; Cohen, R. J. (1999). "Maser mapping of small-scale structure in the circumstellar envelope of S Persei". Monthly Notices of the Royal Astronomical Society 306 (4): 954–974. Bibcode:1999MNRAS.306..954R. doi:10.1046/j.1365-8711.1999.02606.x. ISSN 0035-8711.
- ↑ Famaey, B.; Jorissen, A.; Luri, X.; Mayor, M.; Udry, S.; Dejonghe, H.; Turon, C. (2005). "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data". Astronomy and Astrophysics 430 (1): 165–186. Bibcode:2005A&A...430..165F. doi:10.1051/0004-6361:20041272. ISSN 0004-6361.
- 1 2 Asaki, Y.; Deguchi, S.; Imai, H.; Hachisuka, K.; Miyoshi, M.; Honma, M. (2010). "DISTANCE AND PROPER MOTION MEASUREMENT OF THE RED SUPERGIANT, S PERSEI, WITH VLBI H2O MASER ASTROMETRY". The Astrophysical Journal 721 (1): 267–277. Bibcode:2010ApJ...721..267A. doi:10.1088/0004-637X/721/1/267. ISSN 0004-637X.
- ↑ Zhang, B.; Reid, M. J.; Menten, K. M.; Zheng, X. W.; Brunthaler, A. (2012). "The distance and size of the red hypergiant NML Cygni from VLBA and VLA astrometry". Astronomy & Astrophysics 544: A42. Bibcode:2012A&A...544A..42Z. doi:10.1051/0004-6361/201219587. ISSN 0004-6361.
| ||||||||||||||||||||||||||||||||||
This article is issued from Wikipedia - version of the Wednesday, January 13, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.