Chaldean Order of Planets

Definition

An alternate spelling of the Chaldean order — the traditional planetary sequence Saturn → Jupiter → Mars → Sun → Venus → Mercury → Moon, arranged from slowest to fastest in apparent geocentric motion. Read outward from Earth the same sequence gives the classical cosmological sphere arrangement (Moon nearest, Saturn at the eighth sphere bordering the fixed stars). The 'of planets' phrasing is the standard scholarly form used in classical-astrology surveys to distinguish the planetary-order doctrine from the ethnographic 'Chaldean' label denoting Babylonian astronomer-priests.

In Tradition

Across the Hellenistic, Arabic, and medieval Latin lineages the Chaldean order is the structural backbone of three derivative doctrines: face (decan) rulership cycling from 0° Aries, the planetary hours cycling through the daylight, and the planetary days of the week. Obert reads the order cosmologically as the Spirit–Matter polarity (Saturn at the outermost sphere, Moon nearest Earth); Lehman ties the same sequence to face-table, planetary-hour, and weekday rotation.

In Practice

Practitioners use the order in three overlapping computations. First, faces: starting at 0° Aries with Mars and stepping through Saturn → Jupiter → Mars → Sun → Venus → Mercury → Moon every ten degrees yields the 36 decanal face-rulers. Second, planetary days: each day of the week takes the planet that rules its first hour of daylight, producing Sun-Sunday, Moon-Monday, Mars-Tuesday, and so on. Third, planetary hours: from sunrise, each subsequent hour rotates through the Chaldean order, providing both a Lord of the Hour and the Lord of the Day. The Zoller edition of Liber Hermetis applies the same order to decan-rulership beginning from Mars rather than from Saturn.

Historical Origin

Named for the Chaldeans — the Hellenistic-era label for Babylonian astronomer-astrologers — the order was preserved through Ptolemy, Firmicus, the Arabic transmission, and the medieval Latin tradition. Bonatti's Liber Astronomiae Vol XI Part III Ch XI is the canonical Latin treatment of the planetary-day-and-hour doctrine; Zoller's translation of Liber Hermetis Chapter I applies the same order to decan rulership. Obert and Lehman are the standard modern English-language presentations.

Etymology

Origin: Greek / Latin. Meaning: 'Chaldean' from Greek Χαλδαϊκός (Chaldaikos), 'pertaining to the Chaldeans (the Babylonian astronomer-astrologers)'; 'order of planets' translates the Latin ordo planetarum, the medieval rendering of the Greek ταξίς (taxis)..

Further Reading

• Guido Bonatti, Liber Astronomiae
• Lee Lehman, Essential Dignities
• Charles Obert, The Classical Seven Planets