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Eridanus Constellation
Constellation Eridanus

Eridanus, the River (Eri)

The constellation of Eridanus, the River, is best viewed in the Winter season during the month of December for mid-northern latitudes. It's brightest star is Achernar at magnitude 0.46. The boundary of the Eridanus constellation contains 26 stars that host known exoplanets.

The naked eye can generally see up to magnitude 6 (magnitude 8 with perfect eyes under ideal super dark-sky conditions).

      1. Meaning:
      2. River
      1. Genitive:
      2. Eridani
      1. Abbreviation:
      2. Eri
      1. Constellation Family:
      2. Heavenly Waters
      1. Best Viewing Month*:
      2. December
      1. Circumpolar** (N=northern, S=southern):
      2. S
      1. Right Ascension (avg):
      2. 3h 53m
      1. Declination (avg):
      2. -17° 59'
      1. Brightest Star:
      2. Achernar (0.46m)
      1. Exoplanet Host Stars:
      2. 26
      1. Triple Stars:
      2. 1

    * For southern latitudes, flip the season listed. For example, if a constellation is listed as best viewed in the summer in the month of July, in the southern hemisphere the constellation would be best viewed in the winter in January and would be upside-down.

    ** Circumpolar constellations are visible year-round in the hemisphere listed.



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