Omega2 Cygni
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Cygnus |
| Right ascension | 20h 31m 18.81655s |
| Declination | +49° 13′ 13.0638″ |
| Apparent magnitude (V) | 5.5292±0.0013 |
| Characteristics | |
| Evolutionary stage | AGB |
| Spectral type | M2 III |
| B−V color index | 1.566±0.007 |
| Variable type | Suspected |
| Astrometry | |
| Radial velocity (Rv) | −64.15±0.20 km/s |
| Proper motion (μ) | RA: +8.959 mas/yr Dec.: −32.092 mas/yr |
| Parallax (π) | 7.1833±0.0675 mas |
| Distance | 454 ± 4 ly (139 ± 1 pc) |
| Absolute magnitude (MV) | +0.00 |
| Details | |
| Mass | 1.4 M☉ |
| Radius | 45 R☉ |
| Luminosity | 398 L☉ |
| Surface gravity (log g) | 2.02 cgs |
| Temperature | 3,920 K |
| Metallicity [Fe/H] | −0.10 dex |
| Other designations | |
| ω2 Cyg, 46 Cygni, BD+48°3154, HD 195774, HIP 101243, HR 7851, SAO 49741 | |
| Database references | |
| SIMBAD | data |
Omega2 Cygni is a solitary star in the northern constellation of Cygnus. Its name is a Bayer designation that is Latinized from ω2 Cygni and abbreviated Omega2 Cyg or ω2 Cyg. This star has an apparent visual magnitude of 5.5, which is faintly visible to the naked eye on a dark night. Based upon an annual parallax shift of 7.18 mas, it is located approximately 454 light years from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of 0.08 due to interstellar dust.
This is a red giant star on the asymptotic giant branch, with a stellar classification of M2 III. Having exhausted the supply of hydrogen at its core, it has expanded to 45 times the Sun's radius. The star has 1.4 times the mass of the Sun, and is radiating 398 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,920 K.
It is a suspected variable star, although the evidence is considered "doubtful or erroneous". If it does exist, the variability is small with an amplitude of 0.05 magnitude and a timescale of around 30 days. There is a 58.3% chance that this star is a member of the Hercules stream.
References
- 1 2 3 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. XHIP record for this object at VizieR.
- 1 2 3 4 5 6 7 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- 1 2 3 4 5 Famaey, B.; et al. (January 2005). "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters". Astronomy and Astrophysics. 430 (1): 165–186. arXiv:astro-ph/0409579. Bibcode:2005A&A...430..165F. doi:10.1051/0004-6361:20041272. S2CID 17804304.
- 1 2 3 Eggen, Olin J. (July 1992). "Asymptotic giant branch stars near the sun". Astronomical Journal. 104 (1): 275–313. Bibcode:1992AJ....104..275E. doi:10.1086/116239.
- 1 2 Percy, John R.; Fleming, David E. B. (February 1992). "A photometric survey of suspected small-amplitude red variables". Publications of the Astronomical Society of the Pacific. 104: 96–100. Bibcode:1992PASP..104...96P. doi:10.1086/132963.
- 1 2 3 4 5 6 Khalatyan, A.; et al. (2024). "Transferring spectroscopic stellar labels to 217 million Gaia DR3 XP stars with SHBoost". Astronomy and Astrophysics. 691: A98. arXiv:2407.06963. Bibcode:2024A&A...691A..98K. doi:10.1051/0004-6361/202451427.
- 1 2 3 4 Fetherolf, Tara; et al. (2023). "Variability Catalog of Stars Observed during the TESS Prime Mission". The Astrophysical Journal Supplement Series. 268 (1): 4. arXiv:2208.11721. Bibcode:2023ApJS..268....4F. doi:10.3847/1538-4365/acdee5.
- ↑ "ome02 Cyg". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-02-22.
- ↑ Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869–879. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. S2CID 14878976.