SkyEye: Eridanus

The River

Abbreviation:	Eri
Genitive:	Eridani
Origin:	[antiquity]
Fully Visible:	89°S – 32°N

One Greek myth associates this river with the path followed by Phaëton when he attempted to drive his father Helios' sky chariot. Phaëton couldn't control the chariot and it veered wildly in all directions, scorching heaven and earth. Zeus, king of the gods, struck Phaëton dead with a thunderbolt. Phaëton fell to earth and his body landed in the Po River, which is called Eridanos in ancient Greek.

This is one of the largest of the modern constellations and is the 'tallest', spanning nearly 60° in declination. A number of obsolete constellations have borrowed stars from it in the past, including Psalterium Georgii and Sceptrum Brandenburgicum (see below).

The constellation of Eridanus

Notable Features

Visible Named Stars
α Eri	Achernar	The brightest star in the constellation is actually first magnitude.
β Eri	Cursa	The name of this star means 'footstool' and reflects its position near the foot of Orion.
γ Eri	Zaurak	This third-magnitude star is the standard for the spectral class M0Ⅲ-Ⅲb.
δ Eri	Rana	The origin of the name of this high-proper-motion star is uncertain.
ε Eri	Ran	This is one of the closest stars to the Sun and one of the few nearby stars that is visible to the naked eye. It is known to have at least one exoplanet.
ζ Eri	Zibal	The name applies to the brighter component of this binary star.
η Eri	Azha	This K-type giant star exhibits high proper motion.
θ¹ Eri	Acamar	Acamar appears as a binary star through a telescope. It sometimes appears as Dalim (from the Arabic al‑ẓalīmān meaning 'the two male ostriches') in older star atlases and catalogues.
ο¹ Eri	Beid	For Arabic astronomers, this part of the sky was inhabited by ostriches. 'Beid' means 'the eggs'.
ο² Eri	Keid	A telescope reveals that Keid is a multiple star system.
τ² Eri	Angetenar	This star is aptly named as it marks 'the bend in the river'.
υ² Eri	Theemin	The name of this star also means 'the bend in the river'.
υ³ Eri	Beemim	As does this one!
53 Eri	Sceptrum	The name of this star is taken from the name of the obsolete constellation Sceptrum Brandenburgicum of which it was the brightest member.
Other Interesting Stars
CD−23 1056	Koeia	This tenth-magnitude star is known to have at least one exoplanet. It is located just south of Angetenar (τ² Eri).
CD−30 1812	Montuno	Located halfway between τ⁷ Eri and g Eri, this tenth-magnitude star is known to have at least one exoplanet.
HD 18742	Ayeyarwady	This eighth-magnitude star is known to have at least one exoplanet and is found north of the star τ³ Eri.
HD 30856	Mouhoun	This eighth-magnitude star is known to have at least one exoplanet. It is located near the border with Lepus.
WASP‑22	Tojil	This twelfth-magnitude star is known to have at least one exoplanet and is lurking just south of τ⁵ Eri.
WASP‑50	Chaophraya	Found near Azha (η Eri), this twelfth-magnitude star is known to have at least one exoplanet.
Meteor Shower Radiants
191 ERI	η Eridanids	There are no major meteor showers associated with this constellation. This minor shower is active from late July to mid-August, peaking around 8 August. It may be associated with the comet C/1852 K1 Chacornac.