Epsilon Cygni

light-years
Proper names: Epsilon Cygni, 53 Cygni, Gienah
Catalog numbers:
     Gliese (Gl) 806.1, Henry Draper (HD) 197989, Bonner Durchmusterung (BD) +33°4018, Luyten Half-Second (LHS) 5358, Hipparcos Input Catalog (HIC) 102488, Smithsonian Astrophysical Observatory (SAO) 70474, Aitken Double Star (ADS) 14274, Fifth Fundamental Catalogue (FK5) 780, Hoffleit Bright Star (HR) 7949, S.W. Burnham (BU) 676, Woolley (Wo) 9707
Heavy element abundance: 90% of Sol
Standard error in heavy element abundance: 9%
Source for heavy element abundance: Strobel [Fe/H] Determinations
Arity: binary
Right Ascension and Declination: 20h46m12.684s, +33°58'12.92" (epoch 2000.0)
Distance from Sol: 72.1 light-years (22.1 parsecs)
Standard error in distance: 1.1575%
Source for distance: Hipparcos
Celestial (X,Y,Z) coordinates in ly: 39.6, -44.7, 40.3
Galactic (X,Y,Z) coordinates in ly: 16.9, 69.7, -7.44
Proper motion: 0.484 arcsec/yr (47.2° from north)
Radial Velocity: -10.9 km/sec
Source for proper motion and radial velocity: Gliese
Galactic (U,V,W) velocity components in km/s: -51.5, 0.56, -6.17

What do all these fields mean?

Data for A and B's orbit around one other:
Combined absolute visual magnitude: +0.78
Combined visual luminosity: 42.5 x Sol
Observed Separation: 1723 A.U.s
As seen from A:
     B would appear as magnitude -3.71
As seen from B:
     A would appear as magnitude -14.61


Component A:
NOTE: This star is actually a close-orbiting binary pair. The data below are for both sub-components of the pair combined.
Spectral class: K0
Luminosity Class: III
Apparent visual magnitude: +2.50
Absolute visual magnitude: +0.78
Visual luminosity: 42.5 x Sol
Color indices: B-V= +1.03, U-B= +0.87
Diameter: 15.2 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 6.52 A.U.s
Angular size of star in sky in CZ: 1.242405 degrees


Component B:
Catalog numbers:
     Luyten Two-Tenth (LTT) 16072
Right Ascension and Declination: 20h44m5s, +33°46'48" (epoch 1950.0)
Celestial (X,Y,Z) coordinates in ly: 39.3, -45.2, 40.1
Galactic (X,Y,Z) coordinates in ly: 17.4, 69.6, -7.15
Proper motion: 0.48 arcsec/yr (47.5° from north)
Radial Velocity: -10.9 km/sec
Source for proper motion and radial velocity: Gliese
Galactic (U,V,W) velocity components in km/s: -51.0, 0.79, -6.70
Spectral class: M4
Luminosity Class: V
Apparent visual magnitude: +13.40
Absolute visual magnitude: +11.68
Visual luminosity: 0.0019 x Sol
Color indices: B-V= +1.66, R-I= +1.11
Diameter: 0.36 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 0.043 A.U.s
Angular size of star in sky in CZ: 4.455552 degrees

light-years
but not more than light-years away
Data for this star system were most recently updated on 4-April-2001.