Achernar

light-years
Proper names: Achernar, Alpha Eridani
Catalog numbers:
     Henry Draper (HD) 10144, Hipparcos Input Catalog (HIC) 7588, Cape Photographic Durchmusterung (CPD) -57°334, Smithsonian Astrophysical Observatory (SAO) 232481, Fifth Fundamental Catalogue (FK5) 54
Arity: singular
Points of interest:
     The figure listed for diameter is the star's diameter from pole-to-pole. Measurements at the VLT Interferometer at the Paranal Observatory have shown the star to be 50-60% bigger across at its equator. The star is shaped like a flattened ellipsoid due to very rapid rotation.

Right Ascension and Declination: 1h37m42.852s, -57°14'12.18" (epoch 2000.0)
Distance from Sol: 144 light-years (44.1 parsecs)
Standard error in distance: 2.4516%
Source for distance: Hipparcos
Celestial (X,Y,Z) coordinates in ly: 70.9, 32.2, -121
Galactic (X,Y,Z) coordinates in ly: 25.6, -69.6, -123
Proper motion: 0.101 arcsec/yr (110.2° from north)
Radial Velocity: 16 km/sec
Source for proper motion and radial velocity: Hipparcos Input Catalog
Galactic (U,V,W) velocity components in km/s: -7.85, -24.5, -6.49

What do all these fields mean?


Spectral class: B3p
Luminosity Class: V
Apparent visual magnitude: +0.45
Absolute visual magnitude: -2.77
Visual luminosity: 1116 x Sol
Color indices: B-V= -0.16
Mass: 6.4 x Sol
Diameter: 7.68 x Sol
Source for diameter: VLT Interferometer, ESO Paranal Observatory
Comfort Zone (visual): 33.4 A.U.s
Orbital period in CZ: 76.3231 years
Tidal index in CZ: 0.000172
Angular size of star in sky in CZ: 0.122508 degrees

light-years
but not more than light-years away
Data for this star system were most recently updated on 14-June-2003.