Phi Cygni

Phi Cygni

Observation data Epoch J2000      Equinox J2000
Constellation	Cygnus
Right ascension	19^h 39^m 22.60591^s [1]
Declination	30° 09′ 11.9604″ [1]
Apparent magnitude (V)	4.69 [2]
Characteristics
Spectral type	G8III-IV [3]
B−V color index	+0.96 [2]
Astrometry
Radial velocity (Rv)	+4.50[4] km/s
Proper motion (μ)	RA: +2.48[2] mas/yr Dec.: +36.50[2] mas/yr
Parallax (π)	12.25 ± 0.24[1] mas
Distance	266 ± 5 ly (82 ± 2 pc)
Absolute magnitude (MV)	0.13 [5]
Details
Radius	7.80 [6] R☉
Other designations
12 Cygni, FK5 3570, GC 27203, HIP 96683, HR 7478, HD 185734, SAO 68637, WDS J19394+3009AB [2]
Database references
SIMBAD	data

Phi Cygni (φ Cyg) is a class G8III^[3] (yellow giant) star in the constellation Cygnus. Its apparent magnitude is 4.69^[2] and it is approximately 266 light years away based on parallax.^[1] It is a spectroscopic binary with two similar stars orbiting with a period of 434 days.^[7][8]

References

1. 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. Vizier catalog entry
2. "Phi Cygni". SIMBAD Astronomical Database. Retrieved 2016-04-10.
3. Jaschek, M. (July 1978), "Catalogue of selected spectral types in the MK system", Bulletin d'Information du Centre de Donnees Stellaires 15 (121), Bibcode:1978BICDS..15..121J Vizier catalog entry
4. Pourbaix, D.; Tokovinin, A. A.; Batten, A. H.; Fekel, F. C.; Hartkopf, W. I.; Levato, H.; Morrell, N. I.; Torres, G.; Udry, S. (September 2004), "SB9: The ninth catalogue of spectroscopic binary orbits", Astronomy and Astrophysics 424: 727–732, arXiv:astro-ph/0406573, Bibcode:2004A&A...424..727P, doi:10.1051/0004-6361:20041213
5. Absolute magnitude calculated as $M = m + 5 (1 + \log_{10}{p})\!\,$, where $M$ is the star's absolute magnitude, $m$ is the star's apparent magnitude, and $p$ is the star's measured parallax in arcseconds.
6. Pasinetti Fracassini, L. E.; Pastori, L.; Covino, S.; Pozzi, A. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition", Astronomy and Astrophysics 367: 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451 Vizier catalog entry
7. Malkov, O. Yu.; et al. (October 2012), "Dynamical masses of a selected sample of orbital binaries", Astronomy & Astrophysics 546 (A69), Bibcode:2012A&A...546A..69M, doi:10.1051/0004-6361/201219774 Vizier catalog entry
8. 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 Vizier catalog entry