Astronomy:15 Cygni
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Cygnus |
| Right ascension | 19h 44m 16.60522s[1] |
| Declination | +37° 21′ 15.6771″[1] |
| Apparent magnitude (V) | 4.90[2] |
| Characteristics | |
| Spectral type | G8 III[2] |
| B−V color index | 0.931[3] |
| Astrometry | |
| Radial velocity (Rv) | −23.62±0.21[4] km/s |
| Proper motion (μ) | RA: +72.660[1] mas/yr Dec.: +35.708[1] mas/yr |
| Parallax (π) | 11.0063 ± 0.1188[1] mas |
| Distance | 296 ± 3 ly (90.9 ± 1.0 pc) |
| Absolute magnitude (MV) | 0.19[5] |
| Details | |
| Mass | 2.30[3] M☉ |
| Radius | 12[4] R☉ |
| Luminosity | 93.3[3] L☉ |
| Surface gravity (log g) | 2.8[4] cgs |
| Temperature | 4,920±61[3] K |
| Metallicity [Fe/H] | −0.14[4] dex |
| Rotational velocity (v sin i) | 2.8[4] km/s |
| Age | 1.50[3] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
15 Cygni is a single[7] star in the northern constellation Cygnus. With an apparent visual magnitude of 4.90,[2] it is a faint star but visible to the naked eye. The distance to 15 Cygni can be estimated from its annual parallax shift of 11.0 mas,[1] which yields a separation of some 296 light years. It is moving closer to the Sun with a heliocentric radial velocity of −23.6 km/s.[4]
This is an aging giant star with a stellar classification of G8 III,[2] having consumed the hydrogen at its core and evolved off the main sequence. It is a red clump giant,[8] which means it is generating energy via helium fusion at its core. The star is 1.50 billion years old with 2.3 times the mass of the Sun,[3] and has expanded to 12 times the Sun's radius.[4] It is radiating 93 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,920 K.[3]
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 Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series 71: 245, doi:10.1086/191373, Bibcode: 1989ApJS...71..245K.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Luck, R. Earle (2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal 150 (3): 88, doi:10.1088/0004-6256/150/3/88, Bibcode: 2015AJ....150...88L.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Massarotti, Alessandro et al. (January 2008), "Rotational and Radial Velocities for a Sample of 761 Hipparcos Giants and the Role of Binarity", The Astronomical Journal 135 (1): 209–231, doi:10.1088/0004-6256/135/1/209, Bibcode: 2008AJ....135..209M
- ↑ Takeda, Yoichi et al. (February 2005), "Stellar Parameters and Photospheric Abundances of Late-G Giants: Properties of the Targets of the Okayama Planet Search Program", Publications of the Astronomical Society of Japan 57 (1): 109–125, doi:10.1093/pasj/57.1.109, Bibcode: 2005PASJ...57..109T.
- ↑ "15 Cyg". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=15+Cyg.
- ↑ 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, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode: 2008MNRAS.389..869E.
- ↑ Alves, David R. (August 2000), "K-Band Calibration of the Red Clump Luminosity", The Astrophysical Journal 539 (2): 732–741, doi:10.1086/309278, Bibcode: 2000ApJ...539..732A.
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