Pleiades

Definition

The Pleiades are a striking open star cluster in Taurus — you may know them as the Seven Sisters, or as M45 in the Messier catalog. The cluster lies roughly 444 light-years away, and on a given night six or seven of its stars show to the naked eye. Today it sits at about 0 degrees Gemini along the zodiac (adjusted for precession; classical observers placed it in late Taurus). Babylonian astronomy called it MUL.MUL — "the Stars" above all others.

In Tradition

In Babylonian and Hellenistic astronomy, the Pleiades are the reference cluster of the fixed-star sky: MUL.MUL heads both the Path-of-the-Moon list and the MUL.APIN catalog. In the Western tradition (Robson 1923, public domain; Brady), the cluster is read as granting keen sight and a perceptive mind, but with a shadow — the old phrase is "something to weep about," vision shadowed by grief or loss. Its mythology turns up worldwide — Greek, Aboriginal Australian, Japanese, Native American — reflecting its visibility rather than one shared doctrine.

In Practice

Astrologers working with fixed stars count the Pleiades as active in a chart when a natal planet or angle falls within roughly one to two degrees of the cluster's position along the zodiac, or when it is paran-related — sharing a sky-angle by latitude, in Brady's method. The traditional reading folds vision and ambition together with attendant grief; modern Western practice tends to soften that older "something to weep about" framing toward broader themes of sharp perception and shared, collective vision. The cluster also appears in talismanic-magic lineages: the Hermes 15 Stars manuscript places the Pleiades at "0 Gem 14," with rock crystal as its stone and fennel-seed as its herb for talismanic timing.

Historical Origin

Babylonian attestation: MUL.MUL heads the MUL.APIN Path-of-the-Moon list (c. 1000 BCE). Greek attestation: Hesiod's *Works and Days*; Homer's *Iliad* XVIII.486-488; Aratus' *Phaenomena* 254-267. The Hellenistic astrological reception is in Ptolemy's *Tetrabiblos* III.13 (the Pleiades in the eye of the Bull). Robson (1923, public domain) is the pre-modern Western survey; Brady's *Brady's Book of Fixed Stars* is the modern reference. The Hermes 15 Stars Renaissance manuscript places the Pleiades among the fifteen Behenian fixed stars.

Etymology

Origin: Greek. Meaning: From Greek Pleiades, possibly from plein ("to sail") — the cluster's heliacal rising signaled the start of the sailing season — or from pleios ("many, full").

Further Reading

• Vivian E. Robson, The Fixed Stars and Constellations in Astrology
• Bernadette Brady, Brady's Book of Fixed Stars
• John Michael Greer (trans.), Hermes on the Fifteen Fixed Stars