Eridanus (constellation)

Stars

At its southern end is the magnitude 0.5 star Achernar, designated Alpha Eridani. It is a blue-white hued main sequence star 144 light-years from Earth, whose traditional name means "the river's end".^[1] Achernar is a very peculiar star because it is one of the flattest stars known. Observations indicate that its radius is about 50% larger at the equator than at the poles. This distortion occurs because the star is spinning extremely rapidly.

There are several other noteworthy stars in Eridanus, including some double stars.

NGC 1535 is a small blue-gray planetary nebula visible in small amateur telescopes, with a disk visible in large amateur instruments. 2000 light-years away, it is of the 9th magnitude.^[1]

A portion of the

Eridanus contains the galaxies NGC 1232, NGC 1234, NGC 1291 and NGC 1300, a grand design barred spiral galaxy.

NGC 1300 is a face-on barred spiral galaxy located 61 (plus or minus 8) million light-years away. The center of the bar shows an unusual structure: within the overall spiral structure, a grand design spiral that is 3,300 light-years in diameter exists.^[6] Its spiral arms are tightly wound.^[7]

Meteor showers

The

According to one theory, the Greek constellation takes its name from the Babylonian constellation known as the Star of Eridu (MUL.NUN.KI). Eridu was an ancient city in the extreme south of Babylonia; situated in the marshy regions it was held sacred to the god Enki-Ea who ruled the cosmic domain of the Abyss - a mythical conception of the fresh-water reservoir below the Earth's surface.^[11]

Eridanus is connected to the myth of Phaethon, who took over the reins of his father Helios' sky chariot (i.e., the Sun),^[1] but didn't have the strength to control it and so veered wildly in different directions, scorching both Earth and heaven. Zeus intervened by striking Phaethon dead with a thunderbolt and casting him to Earth. The constellation was supposed to be the path Phaethon drove along; in later times, it was considered a path of souls. Since Eridanos was also a Greek name for the Po (Latin Padus), in which the burning body of Phaethon is said by Ovid to have extinguished, the mythic geography of the celestial and earthly Eridanus is complex.^[12]

Another association with Eridanus is a series of rivers all around the world. First conflated with the

• Eridanus (Chinese astronomy)
• List of brightest stars

Citations

References

• Ridpath, Ian; Tirion, Wil (2001), Stars and Planets Guide, Princeton University Press,
  ISBN 0-691-08913-2
• Ridpath, Ian; Wil Tirion (2007). Stars and Planets Guide. London: Collins.
  ISBN 978-0-00-725120-9
  .
• Ridpath, Ian; Wil Tirion (2007). Stars and Planets Guide. Princeton: Princeton University Press.
  ISBN 978-0-691-13556-4
  .
• Star Names, Their Lore and Meaning, Richard Hinckley Allen, New York City, Dover, various dates

External links

Wikimedia Commons has media related to:
Eridanus (category)

• The Deep Photographic Guide to the Constellations: Eridanus
• The clickable Eridanus
• Epsilon Eridani
• New 'Vulcan' Planet Tantalizes Astronomers Archived 2001-02-19 at the Wayback Machine
• Starry Night Photography - Eridanus Constellation
• Ian Ridpath's Star Tales – Eridanus
• Warburg Institute Iconographic Database (medieval and early modern images of Eridanus)