Resources / Celestial timing
Lunar Mansion Calculator
Locate the Moon within the twenty-eight lunar mansions, using the equal 28-mansion division of the tropical zodiac, and see its true place, the mansion's Arabic name and meaning, the stars that mark it, and what Agrippa wrote of it.
Preparing the mansions for your moment
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 West received the system as the Arabic manāzil al-qamar, which on Kunitzsch's account took the Indian scheme of lunar stations, the nakṣatras, and named its stations from the Arabs' own star lore. China counts twenty-eight lunar lodges of its own; whether the Indian and Chinese schemes share an origin is still argued.
Reading the instrument
- The ring sets the twenty-eight mansions on the tropical zodiac, with the Moon at its true place for the moment shown and its phase drawn as seen. The mansion it stands in is lit; any other can be opened from the ring or the list.
- Twenty-eight stations do not divide 360° evenly; each spans 12°51'26" (Agrippa's "twelve degrees, and one and fifty minutes, and almost twenty six seconds") 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
- Agrippa, Three Books of Occult Philosophy, II.33
- "Of the twenty eight Mansions of the Moon, and their virtues": the names, glosses and effects the instrument paraphrases, the list most later European sources reproduce (Barrett's Magus of 1801 copies it nearly word for word).
- Picatrix (Ghāyat al-Ḥakīm) I.4
- The source of most of Agrippa's electional material on the mansions, with differences of detail.
- Kunitzsch, "al-Manāzil", Encyclopaedia of Islam
- The Arabic names, their meanings and the stars that mark each station in the Arabic tradition.
What this does not claim
The Moon is computed to within about 15″ of a reference ephemeris, half a minute of its motion, so a change of mansion is timed to within about 30 seconds. The frame is a choice: mansions here are the equal tropical division from the vernal equinox. Agrippa places them in the eighth sphere, a star-fixed zodiac; read that way they would fall about two mansions earlier in 2026. The effects shown are modern paraphrases of the 1651 English, not quotations, and make no claim of effect.