Mu Cygni
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Cygnus |
Right ascension | 21h 44m 08.57793s[1] |
Declination | 28° 44′ 33.4731″[1] |
Apparent magnitude (V) | 4.50[2] |
Characteristics | |
Spectral type | F6V + G2V[3] |
B−V color index | +0.47[2] |
Astrometry | |
Radial velocity (Rv) | +16.95[4] km/s |
Proper motion (μ) | RA: +260.72[2] mas/yr Dec.: -243.21[2] mas/yr |
Parallax (π) | 44.97 ± 0.43[1] mas |
Distance | 72.5 ± 0.7 ly (22.2 ± 0.2 pc) |
μ1 Cyg | |
Absolute bolometric magnitude (Mbol) | ±0.06 2.91[5] |
μ2 Cyg | |
Absolute bolometric magnitude (Mbol) | ±0.06 4.32[5] |
Orbit[6] | |
Period (P) | 789 yr |
Semi-major axis (a) | 5.32″ |
Eccentricity (e) | 0.66 |
Inclination (i) | 75.5° |
Longitude of the node (Ω) | 110.1° |
Periastron epoch (T) | 1958.0 |
Argument of periastron (ω) (secondary) | 145.7° |
Details[5] | |
μ1 Cyg | |
Mass | 1.35 M☉ |
Radius | ±0.07 1.88 R☉ |
Surface gravity (log g) | ±0.10 4.05 cgs |
Temperature | ±80 6,350 K |
Metallicity [Fe/H] | ±0.07 −0.18 dex |
Rotational velocity (v sin i) | ±0.8 9.6 km/s |
μ2 Cyg | |
Mass | 1.02 M☉ |
Radius | ±0.05 1.08 R☉ |
Surface gravity (log g) | ±0.10 4.30 cgs |
Temperature | ±100 6,055 K |
Rotational velocity (v sin i) | ±1.0 2.5 km/s |
Other designations | |
μ1 Cyg: HD 206826, HR 8309, SAO 89940[7] | |
μ2 Cyg: HD 206827, HR 8310, SAO 89939[8] | |
Database references | |
SIMBAD | μ Cyg |
μ1 Cyg | |
μ2 Cyg |
μ Cygni (Latinised as Mu Cygni) is a binary star[9] in the constellation Cygnus. Located around 22.24 parsecs (72.5 ly) distant, the system has a combined apparent magnitude of 4.50.[2] The primary, with an apparent magnitude of 4.69, has a spectral type of F6V,[7] and the secondary, with an apparent magnitude of 6.12, has a spectral type of G2V.[8] Their orbit has a period of around 800 years, with a semimajor axis of 5" and an eccentricity around 0.6.[10]
Two reported additional components, C (apparent magnitude 12.93) and D (apparent magnitude 6.94), are believed to be optical doubles rather than part of the Mu Cygni system.[3] Component D is the more distant spectroscopic binary HD 206874 (HIP 107326), consisting of two early F-type subgiants.[11]
References
- 1 2 3 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
- 1 2 3 4 5 6 "CCDM J21442+2845AB". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-04-08.
- 1 2 Mason, Brian D.; et al. (December 2001), "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog", The Astronomical Journal, 122 (6): 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920 Vizier catalog entry
- ↑ Maldonado, J.; Martínez-Arnáiz, R. M.; Eiroa, C.; Montes, D.; Montesinos, B. (October 2010), "A spectroscopy study of nearby late-type stars, possible members of stellar kinematic groups", Astronomy and Astrophysics, 521: A12, arXiv:1007.1132, Bibcode:2010A&A...521A..12M, doi:10.1051/0004-6361/201014948
- 1 2 3 Fuhrmann, Klaus (2011). "Nearby stars of the Galactic disc and halo - V". Monthly Notices of the Royal Astronomical Society. 414 (4): 2893. Bibcode:2011MNRAS.414.2893F. doi:10.1111/j.1365-2966.2011.18476.x.
- ↑ Pourbaix, D.; et al. (2004), "SB9: The Ninth Catalogue of Spectroscopic Binary Orbits", Astronomy & Astrophysics, 424 (2): 727–732, arXiv:astro-ph/0406573, Bibcode:2009yCat....102020P, doi:10.1051/0004-6361:20041213.
- 1 2 "HR 8309". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 13 January 2014.
- 1 2 "HR 8310". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 13 January 2014.
- ↑ Eggleton, P. P.; Tokovinin, A. A. (2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. Vizier catalog entry
- ↑ Malkov, O. Yu.; et al. (October 2012), "Dynamical masses of a selected sample of orbital binaries", Astronomy & Astrophysics, 546 (A69): A69, Bibcode:2012A&A...546A..69M, doi:10.1051/0004-6361/201219774 Vizier catalog entry
- ↑ Abt, Helmut A (2009). "MK Classifications of Spectroscopic Binaries". The Astrophysical Journal Supplement. 180: 117. Bibcode:2009ApJS..180..117A. doi:10.1088/0067-0049/180/1/117.