Epsilon Cygni

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**Epsilon Cygni A/B**
Observation data Epoch J2000
Epsilon Cygni A (53 Cygni) / B (52 Cygni)
Constellation (pronunciation)	Cygnus
Right ascension	20^h 46^m 12.7^s
Declination	+33° 58′ 12.9″
Apparent magnitude (V)	2.50/13.40
Characteristics
Spectral type	K0 III/M3
U-B color index	0.87
B-V color index	1.03/1.66
Variable type	?
Astrometry
Radial velocity (R_v)	−11.5 km/s
Proper motion (μ)	RA: 356.16 mas/yr Dec.: 330.28 mas/yr
Parallax (π)	45.26 ± 0.53 mas
Distance	72.1 ± 0.8 ly (22.1 ± 0.3 pc)
Absolute magnitude (M_V)	1.08/11.99
Visual binary orbit
Companion	Epsilon Cygni B (52 Cygni)
Details
Mass	2–4 M_☉
Radius	12–16 R_☉
Luminosity	40–61 L_☉
Temperature	4,675 K
Metallicity	70% Sun
Age	1.5 &times 10⁹ years
Other designations
Gienah Cygni, Gl Gl 806.1 A/B, HR 7949, BD +33°4018, HD 197989, LHS 5358b/a, GCTP 4959.00, SAO 70474, FK5 780, HIP 102488.
Database references
SIMBAD	data

Epsilon Cygni (ε Cyg / ε Cygni) is a star in the constellation Cygnus. Its traditional name is Gienah, however Gamma Corvi has an identical traditional name.

Epsilon Cygni is a cool orange giant star that is, as many visible stars tend to be, well along in terms of its stellar evolution. While young in comparison to the Sun its larger mass gives it a much shorter lifespan, and the star is in the beginning stages of its death. It's 72 light-years from the earth.

The name "Gienah" derives from the Arabic word for wing, جناح janāħ.