Astronomy:22 Cygni
Observation data Equinox J2000.0]] (ICRS) | |
---|---|
Constellation | Cygnus |
Right ascension | 19h 55m 51.75718s[1] |
Declination | +38° 29′ 12.154″[1] |
Apparent magnitude (V) | 4.95[2] |
Characteristics | |
Spectral type | B5 IV[3] |
B−V color index | −0.086±0.009[2] |
Astrometry | |
Radial velocity (Rv) | −14.8±2.2[4] km/s |
Proper motion (μ) | RA: +6.559[1] mas/yr Dec.: −0.469[1] mas/yr |
Parallax (π) | 3.0418 ± 0.2388[1] mas |
Distance | 1,070 ± 80 ly (330 ± 30 pc) |
Absolute magnitude (MV) | −3.18[2] |
Orbit[5] | |
Period (P) | 78.2±0.4 d |
Eccentricity (e) | 0.17±0.13 |
Periastron epoch (T) | 2443734.5±2.1 JD |
Argument of periastron (ω) (secondary) | 139±11° |
Semi-amplitude (K1) (primary) | 20.7±3.1 km/s |
Details | |
22 Cyg A | |
Mass | 7.9±0.4[6] M☉ |
Radius | 5.6[7] R☉ |
Luminosity | 7,305[8] L☉ |
Surface gravity (log g) | 3.35[9] cgs |
Temperature | 15,200[8] K |
Rotational velocity (v sin i) | 30[10] km/s |
Age | 37.3±4.2[6] Myr |
Other designations | |
Database references | |
SIMBAD | data |
22 Cygni is a binary star system in the northern constellation of Cygnus. It is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of 4.95.[2] The annual shift of 3.0 mas[1] yields a distance estimate of around 1,070 light years. It is moving closer to the Earth with a heliocentric radial velocity of −15 km/s.[4]
This is a single-lined spectroscopic binary with an orbital period of 78.2 days and an eccentricity of roughly 0.17.[5] The visible component has a stellar classification of B5 IV[3] that matches a B-type subgiant star. It is 37[6] million years old with a projected rotational velocity of 30[10] km/s and has an essentially solar metallicity, within the margin of error.[9] The star has eight[6] times the mass of the Sun and about 5.6[7] times the Sun's radius. It is radiating 7,305[8] times the Sun's luminosity from its photosphere at an effective temperature of 15,200 K.[8]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode: 2018A&A...616A...1G. Gaia DR2 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 2.3 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode: 2012AstL...38..331A.
- ↑ 3.0 3.1 Lesh, Janet Rountree (December 1968), "The Kinematics of the Gould Belt: an Expanding Group?", Astrophysical Journal Supplement 17: 371, doi:10.1086/190179, Bibcode: 1968ApJS...17..371L.
- ↑ 4.0 4.1 Gontcharov, G. A. (2006), "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system", Astronomy Letters 32 (11): 759–771, doi:10.1134/S1063773706110065, Bibcode: 2006AstL...32..759G.
- ↑ 5.0 5.1 Abt, Helmut A. et al. (October 1990), "The Frequency and Formation Mechanism of B2--B5 Main-Sequence Binaries", Astrophysical Journal Supplement 74: 551, doi:10.1086/191508, Bibcode: 1990ApJS...74..551A.
- ↑ 6.0 6.1 6.2 6.3 Tetzlaff, N. et al. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society 410 (1): 190–200, doi:10.1111/j.1365-2966.2010.17434.x, Bibcode: 2011MNRAS.410..190T.
- ↑ 7.0 7.1 Pasinetti Fracassini, L. E. et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics 367: 521–524, doi:10.1051/0004-6361:20000451, Bibcode: 2001A&A...367..521P.
- ↑ 8.0 8.1 8.2 8.3 Hohle, M. M. et al. (April 2010), "Masses and luminosities of O- and B-type stars and red supergiants", Astronomische Nachrichten 331 (4): 349, doi:10.1002/asna.200911355, Bibcode: 2010AN....331..349H.
- ↑ 9.0 9.1 Adelman, Saul J. (June 1998), "Elemental abundance analyses with DAO spectrograms - XIX. The superficially normal B stars zeta Draconis, epsilon Lyrae, 8 Cygni and 22 Cygni", Monthly Notices of the Royal Astronomical Society 296 (4): 856–862, doi:10.1046/j.1365-8711.1998.01426.x, Bibcode: 1998MNRAS.296..856A.
- ↑ 10.0 10.1 Abt, Helmut A. et al. (July 2002), "Rotational Velocities of B Stars", The Astrophysical Journal 573 (1): 359–365, doi:10.1086/340590, Bibcode: 2002ApJ...573..359A
- ↑ "22 Cyg". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=22+Cyg.
Original source: https://en.wikipedia.org/wiki/22 Cygni.
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