33 Cygni is a single[7] star located 159 light years away in the northern constellation Cygnus. It is visible to the naked eye as a white-hued star with an apparent visual magnitude of 4.28.[2] The star is moving closer to the Earth with a heliocentric radial velocity of −16 km/s.[5] Eggen (1995) listed it as a proper motion candidate for membership in the IC 2391 supercluster.[9]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cygnus |
| Right ascension | 20h 13m 23.86661s[1] |
| Declination | +56° 34′ 03.7999″[1] |
| Apparent magnitude (V) | 4.28[2] |
| Characteristics | |
| Evolutionary stage | main sequence[3] |
| Spectral type | A3 IV–Vn[4] |
| B−V color index | 0.114±0.001[2] |
| Astrometry | |
| Radial velocity (Rv) | −16.13±2.53[5] km/s |
| Proper motion (μ) | RA: +61.82[1] mas/yr Dec.: +82.18[1] mas/yr |
| Parallax (π) | 20.48 ± 0.12 mas[1] |
| Distance | 159.3 ± 0.9 ly (48.8 ± 0.3 pc) |
| Absolute magnitude (MV) | 0.84[2] |
| Details[3] | |
| Mass | 2.33±0.01 M☉ |
| Radius | 2.76[6] R☉ |
| Luminosity | 44.3±1.0 L☉ |
| Temperature | 8,395+97 −96 K |
| Rotational velocity (v sin i) | 243 km/s |
| Age | 400[7] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This star has a stellar classification of A3 IV–Vn,[4] showing a spectrum with traits intermediate between an A-type main-sequence star and an evolving subgiant star. The 'n' suffix indicates "nebulous" absorption lines due to rapid rotation. It is about 400[7] million years old with a high projected rotational velocity of 243 km/s.[3] This rate of spin is giving the star an oblate shape with a pronounced equatorial bulge that is an estimated 28% wider than the polar radius.[10]
33 Cyg has 2.33[3] times the mass of the Sun and 2.76[6] times the Sun's radius. The star is radiating 44 times the Sun's luminosity from its photosphere at an effective temperature of 8,395 K.[3] It displays an infrared excess that suggests an orbiting debris disk with a temperature of 500 K at a mean distance of 1.80 AU from the host star.[6]
References
edit- ^ a b c d e van Leeuwen, F. (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, S2CID 18759600.
- ^ a b c d 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, S2CID 119257644.
- ^ a b c d e Zorec, J.; et al. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy and Astrophysics, 537: A120, arXiv:1201.2052, Bibcode:2012A&A...537A.120Z, doi:10.1051/0004-6361/201117691, S2CID 55586789.
- ^ a b Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819.
- ^ a b Becker, Juliette C.; et al. (April 2015), "Extracting Radial Velocities of A- and B-type Stars from Echelle Spectrograph Calibration Spectra", The Astrophysical Journal Supplement Series, 217 (2): 13, arXiv:1503.03874, Bibcode:2015ApJS..217...29B, doi:10.1088/0067-0049/217/2/29, S2CID 33968873, 29.
- ^ a b c Cotten, Tara H.; Song, Inseok (July 2016), "A Comprehensive Census of Nearby Infrared Excess Stars", The Astrophysical Journal Supplement Series, 225 (1): 24, arXiv:1606.01134, Bibcode:2016ApJS..225...15C, doi:10.3847/0067-0049/225/1/15, S2CID 118438871, 15.
- ^ a b c De Rosa, R. J.; et al. (2014), "The VAST Survey - III. The multiplicity of A-type stars within 75 pc", Monthly Notices of the Royal Astronomical Society, 437 (2): 1216, arXiv:1311.7141, Bibcode:2014MNRAS.437.1216D, doi:10.1093/mnras/stt1932, S2CID 88503488.
- ^ "33 Cyg". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-01-14.
- ^ Eggen, Olin J. (December 1995), "Reality Tests of Superclusters in the Young Disk Population", Astronomical Journal, 110: 2862, Bibcode:1995AJ....110.2862E, doi:10.1086/117734.
- ^ van Belle, Gerard T. (March 2012), "Interferometric observations of rapidly rotating stars", The Astronomy and Astrophysics Review, 20 (1): 51, arXiv:1204.2572, Bibcode:2012A&ARv..20...51V, doi:10.1007/s00159-012-0051-2, S2CID 119273474.