Alpha Hydri

light-years
Proper names: Alpha Hydri
Catalog numbers:
     Gliese (Gl) 83, Henry Draper (HD) 12311, Cape Photographic Durchmusterung (CPD) -62°162 , Hipparcos Input Catalog (HIC) 9236, Smithsonian Astrophysical Observatory (SAO) 248474, Fifth Fundamental Catalogue (FK5) 72, Hoffleit Bright Star (HR) 591
Arity: singular
Right Ascension and Declination: 1h58m46.201s, -61°34'11.43" (epoch 2000.0)
Distance from Sol: 71.3 light-years (21.9 parsecs)
Standard error in distance: 1.1882%
Source for distance: Hipparcos
Celestial (X,Y,Z) coordinates in ly: 29.5, 16.8, -62.7
Galactic (X,Y,Z) coordinates in ly: 13.7, -39.7, -57.6
Proper motion: 0.27 arcsec/yr (83.0° from north)
Radial Velocity: 15.2 km/sec
Source for proper motion and radial velocity: Gliese
Galactic (U,V,W) velocity components in km/s: -19.5, -24.3, -6.68

What do all these fields mean?


Spectral class: F0
Luminosity Class: V
Apparent visual magnitude: +2.86
Absolute visual magnitude: +1.16
Visual luminosity: 30.0 x Sol
Color indices: B-V= +0.28
Mass: 3 x Sol
Diameter: 3.05 x Sol
Source for diameter: Apparent Diameters and Absolute Radii of Stars (Fracassini+ 1988)
Comfort Zone (visual): 5.47 A.U.s
Orbital period in CZ: 7.3952 years
Tidal index in CZ: 0.018285
Angular size of star in sky in CZ: 0.297461 degrees

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