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Star Lore of the Constellations: Eridanus the River, by Deborah Houlding

Notable stars in Eridanus: Epoch 2000
Longitude Name Nature Mag. Position Lat. Dec.
15 Pis 19 Achernar Jupiter 0.46 Southern end of River 60S 58S

According to the early account of Aratus, Eridanus is a river of tears shed at the death of Phaethon and lifted to the sky to console Apollo for the death of his son.[1] Conflicting reports claim that its earthly equivalent is the Euphrates or the Nile, though it most likely reflects the economic and social importance of all rivers to our ancestors. Since the constellation is separated into a Northern and Southern 'stream', there have been attempts to recognise both the Nile and Euphrates in it. William Ramesey, for example, called the southern part the River Eridanus, and the northern part the River Nilus.[2]

Perhaps because its astrological meaning is obvious, Manilius (and Firmicus after him) made no comment on its influence. But the simple statement from Ptolemy, that constellations pertaining to rivers and streams were associated with their counterparts on earth, would seem to suggest a connection with floods, drowning, aquatic life, trade and travel. [3]

Although Eridanus is the longest constellation in the sky and has a multitude of stars, it possesses only one bright one, Achernar, whose name means 'Mouth of the River'. It marks the southern end of Eridanus and Ptolemy referred to it as "the last bright one", suggesting for this star alone an influence like that of Jupiter while all the other stars in the constellation were likened to Saturn. [4]

Achernar is 1st magnitude and one of the ten brightest stars in the sky. It is reported to have a very beneficial influence and Robson remarks that it "gives success in public office, beneficence, and religion".[5] But generally there has been little written about this star in traditional works - it tended to be ignored because its southerly declination (58S) prevents it appearing in the sky for latitudes above 36N.

Although Eridanus is a long, winding, constellation, its only bright star - Achernar - is so southerly that it is not visible above latitudes of 37 north. Southern hemisphere astrologers will find it if they imagine a line between Canopus (easily identifiable as the brightest star in the Southern hemisphere and second only to Sirius in the whole sky), and Fomalhaut, (the bright star of the constellation Pisces Australis). Achernar lies about 70 degrees to the west of Canopus.

The Sun crosses Achernar around 5th March each year.

Notes & References:
  1 ] Aratus, Phainomena II, (1st cent. BC), v.360. Translated by A.W. Mair and G.R. Mair in Callimachus, Aratus, Lycophron: Hymns, Epigrams. Phaenomena. Alexandra, (Harvard University Press, 1921).
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  2 ] Ramesey, Astrology Restored, p.94 ff.
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  3 ] Ptolemy, Tetrabiblos, II.7
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  4 ] Ibid., I.9
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  5 ] The Fixed Stars and Constellations in Astrology, 1923; p.216
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© Deborah Houlding. First published in The Traditional Astrologer Magazine, issue 16; March 1998. Published online January 2006.

Stars & Constellations