Alpha Eridani


Distance (Light Years) 144 ± 4
Apparent Magnitude 0.45
Color (B-V)-0.16

Names For This Star

The name "Achernar" from the Arabic name for this star: Al Ahir al Nahr, which means "the End of the River". The river to which the name refers is of course, the River Eridanus, which is the constellation to which this star belongs.

Description of the Star

Achernar is a very hot B3Vpe main sequence star blue in color, about 9 times the diameter of the sun and much more luminous. According to Burnham, the surface temperature is around 14,000 K. The temperature and diameter of the star imply a luminosity about 1300 times larger than that of the sun.

Spectral emission lines suggest an expanding shell of gas surrounding the star.

Other Designations For This Star

Hipparcos Identifier (HIP Number)


Harvard Revised (HR Number)


Henry Draper Catalog (HD Number)


Bonner Durchmusterung (BD Number)

CP-57 334
Smithsonian Astrophysical
Observatory compendium (SAO Number)

Fundamental Katalog (FK5 Number)



Copyright © 1998 - 2010 by Arnold V. Lesikar,
Professor Emeritus
Dept. of Physics, Astronomy, and Engineering Science,
St. Cloud State University,St. Cloud, MN 56301-4498

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