Constellation

greek: ἀστροθεσία (astrothesia) / καταστερισμός (katasterismos) · latin: constellatio

Definition

A recognised grouping of stars treated as a single figure or asterism on the celestial sphere — for example Orion, Ursa Major, or Canis Major. Constellations are distinct from the twelve zodiacal signs of tropical astrology, which are 30° arcs of the ecliptic measured from the vernal equinox; the corresponding zodiacal constellations are irregular sky-figures of varying widths along the same band. Sidereal astrology and fixed-star work read planets against the constellations themselves, while tropical astrology reads them against the equinox-anchored signs.

In Tradition

Across the Hellenistic, Egyptian, and Western traditions, constellations function as a layer of meaning underneath the sign system — they supply the iconographic and mythological furniture (the Bull, the Lion, the Twins) that the signs inherit, and they host the fixed stars whose conjunctions to natal planets are read as additional testimony. The relationship between constellation and sign is the precession question that distinguishes tropical from sidereal practice.

In Practice

When reading a chart, astrologers note constellations through the fixed stars within them: a natal planet conjunct Aldebaran (in Taurus the constellation), Regulus (in Leo), Antares (in Scorpius), or Fomalhaut (in Piscis Austrinus) brings the symbolism of that star and constellation into the chart. Constellational identifications also matter in Egyptian and Babylonian-derived material, where each constellation carries its own mythic-iconographic profile (Sah/Orion as the post-mortem destination, Meskhetyu as the Foreleg/Big Dipper). Sidereal-zodiac practice reads the entire chart against the constellations rather than the tropical signs.

Historical Origin

Constellational sky-maps predate horoscopic astrology by millennia. The Egyptian Pyramid Texts (Old Kingdom, ca. 2400-2300 BCE) name Sah (Orion) and Sopdet (Sirius) as the parents of the Morning Star. Babylonian star-catalogues (MUL.APIN, early first millennium BCE) systematise the constellations of the three celestial paths (Anu, Enlil, Ea). The Greek tradition inherits and re-codes these figures through Aratus' Phaenomena (3rd c. BCE), Hipparchus, and Ptolemy's star catalogue in the Almagest, which fixes the canonical 48-constellation set that survives into modern astronomical use.

Etymology

Origin: Latin. Meaning: Standing-with-stars; a pattern of stars.

Definition

In Tradition

In Practice

Historical Origin

Etymology

Further Reading