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Achernar

File:Eridanus_constellation_map.svg · Wikimedia Commons · See Wikimedia Commons

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Achernar is the brightest star in the constellation of Eridanus and the ninth-brightest in the night sky. It has the Bayer designation Alpha Eridani, which is Latinized from α Eridani and abbreviated Alpha Eri or α Eri. The name Achernar applies to the primary component of a binary system. The two components are designated Alpha Eridani A (the primary) and B (the secondary), with the latter known informally as Achernar B. As determined by the Hipparcos astrometry satellite, this system is located at a distance of approximately from the Sun.

AI overview

Achernar is the ninth-brightest star visible in Earth's night sky and the brightest star in the constellation Eridanus, formally designated as Alpha Eridani. It is actually a binary system with two components, with the primary star being the one commonly referred to as Achernar.

AI-generated from the Wikipedia summary — may contain errors.

Astronomical data · SIMBAD

Object type
Be*
Spectral type
B6Vpe
Distance
139 light-years
Redshift
z = 0.000028253277987166925
Coordinates
RA 24.4285° · Dec -57.2368°
View on SIMBAD →

via SIMBAD · CDS Strasbourg

~7 min read

Encyclopedic overview

8 sections
Contents
  • Nomenclature
  • Namesake
  • Properties
  • Co-moving companion
  • Historical visibility
  • Notes
  • References
  • Further reading

Achernar is the brightest star in the constellation of Eridanus and the ninth-brightest in the night sky. It has the Bayer designation Alpha Eridani, which is Latinized from α Eridani and abbreviated Alpha Eri or α Eri. The name Achernar applies to the primary component of a binary system. The two components are designated Alpha Eridani A (the primary) and B (the secondary), with the latter known informally as Achernar B. As determined by the Hipparcos astrometry satellite, this system is located at a distance of approximately from the Sun.

Of the ten brightest stars in the night-time sky by apparent magnitude, Alpha Eridani is the hottest and bluest in color because it is spectral type B. Achernar has an unusually rapid rotational velocity, causing it to become oblate in shape. The secondary is smaller, is spectral type A, and orbits Achernar at a distance of .

Excerpted from Wikipedia’s “Achernar” article, available under the CC BY-SA 4.0 licence.

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