Deneb

light-years
Proper names: Deneb, Alpha Cygni, 50 Cygni, Arided, Al Dhanab al Dajajah
Catalog numbers:
     Henry Draper (HD) 197345, Bonner Durchmusterung (BD) +443541, Aitken Double Star (ADS) 14172, Hoffleit Bright Star (HR) 7924, Smithsonian Astrophysical Observatory (SAO) 49941, Fifth Fundamental Catalogue (FK5) 777, Hipparcos Input Catalog (HIC) 102098, Caltech 2-microns Survey (IRC) +50337
Age: probably just recently post-main-sequence
Arity: singular
Points of interest:
     Deneb may be in the process of expanding from a class A main-sequence star to a red giant.  Theoretically, this process should take only about 20 000 years, at a rate of about 0.3C per year, for a massive star like Deneb.  Hence, Deneb is under close scrutiny for any long-term changes in its spectrum or color temperature.

Right Ascension and Declination: 20h41m25.917s, +45°16'49.31" (epoch 2000.0)
Distance from Sol: 1600 light-years (491 parsecs)
Standard error in distance: 20%
Source for distance: Burnham's Celestial Handbook
Celestial (X,Y,Z) coordinates in ly: 729, -858, 1137
Galactic (X,Y,Z) coordinates in ly: 150, 1592, 52
Proper motion: 0.0036 arcsec/yr (56.3° from north)
Radial Velocity: -4.5 km/sec
Source for proper motion and radial velocity: Hipparcos Input Catalog
Galactic (U,V,W) velocity components in km/s: -8.3, -3.6, -2.7

What do all these fields mean?


Spectral class: A2
Luminosity Class: Ia
Apparent visual magnitude: +1.25 (increasing to +1.20)
Absolute visual magnitude: -7.21 (increasing to -7.26)
Visual luminosity: 66559 x Sol (increasing to 69696 x Sol)
Variable type: Alpha Cygni (pulsating variable)
Color indices: B-V= +0.09
Mass: 25 x Sol
Source for mass: Burnham's Celestial Handbook
Diameter: 116 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 258 A.U.s
Orbital period in CZ: 828.772 years
Tidal index in CZ: 0.000001
Angular size of star in sky in CZ: 0.239678 degrees

light-years
but not more than light-years away
Data for this star system were most recently updated on 3-October-1999.