Betelgeuse

light-years
Proper names: Betelgeuse, Betelgeux, The Martial Star, Alpha Orionis, 58 Orionis
Catalog numbers:
     Henry Draper (HD) 39801, Bonner Durchmusterung (BD) +7°1055, Aitken Double Star (ADS) 4506, Hoffleit Bright Star (HR) 2061, Smithsonian Astrophysical Observatory (SAO) 113271, Fifth Fundamental Catalogue (FK5) 224, Hipparcos Input Catalog (HIC) 27989, Caltech 2-microns Survey (IRC) +10100
Age: post main sequence
Arity: possible spectroscopic binary
Points of interest:
     The diameter listed below is only the average diameter for this star.  Its actual diameter varies from 550 to 920 times Sol.  This may be indicative of instabilities within the star which could turn it into a supernova at any time.

Right Ascension and Declination: 5h55m10.37s, +7°24'25.35" (epoch 2000.0)
Distance from Sol: 427 light-years (131 parsecs)
Standard error in distance: 17.6915%
Source for distance: Hipparcos
Celestial (X,Y,Z) coordinates in ly: 8.9, 424, 55
Galactic (X,Y,Z) coordinates in ly: -397, -145, -62
Proper motion: 0.0275 arcsec/yr (70.9° from north)
Radial Velocity: 21 km/sec
Source for proper motion and radial velocity: Hipparcos Input Catalog
Galactic (U,V,W) velocity components in km/s: -21, -11, 14

What do all these fields mean?


Spectral class: M2
Luminosity Class: Ib
Apparent visual magnitude: +1.30 (increasing to +0.00)
Absolute visual magnitude: -4.29 (increasing to -5.59)
Visual luminosity: 4520 x Sol (increasing to 14968 x Sol)
Variable type: semi-regular (pulsating variable)
Period of variability: 2335 days
Mass: 20 x Sol
Source for mass: Burnham's Celestial Handbook
Diameter: 662 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 67 A.U.s
Orbital period in CZ: 123.263 years
Tidal index in CZ: 0.000066
Angular size of star in sky in CZ: 5.249660 degrees

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