Resources / Celestial timing
Lunar Mansion Calculator
Locate the Moon within the 28 lunar mansions using an approximate ecliptic division and see the Moon’s zodiacal position.
Preparing the instrument for your time and place
The tradition
Where the decans divide the zodiac by the Sun's year, the mansions divide it by the Moon's month. Twenty-eight stations, each roughly 12°51', mark where the Moon rests on successive nights of its circuit.
The system is best documented in the Arabic tradition as the manāzil al-qamar, though comparable lunar station schemes appear independently in Indian and Chinese astronomy — a reminder that the Moon's monthly circuit invites the same solution wherever the sky is watched carefully.
Reading the instrument
- The instrument reports the mansion the Moon occupies for the selected moment, with its zodiacal range.
- Twenty-eight stations do not divide 360° evenly; each spans 12°51'26" and boundaries fall mid-sign rather than at neat degrees.
- Traditional mansion material is strongly electional — it was used to choose moments for undertakings, which is why sources attach activities rather than character readings to each station.
Where it descends from
- Picatrix (Ghāyat al-Ḥakīm)
- The fullest transmission of the mansions into Latin magical literature, with their electional attributions.
- Agrippa, Three Books of Occult Philosophy
- Book II carries the mansion list that most later European sources reproduce.
What this does not claim
The lunar position is an approximation. The Moon moves roughly its own diameter every hour, so mansion boundaries are the place where a compact model is least reliable — verify against a precise ephemeris before acting on a boundary case.