History & development
Onmyodo, Buddhist Sukuyodo and mansion systems should not be collapsed into one Japanese zodiac. Jeffrey Kotyk’s research distinguishes Buddhist ritual-day astrology from Sukuyodo horoscopy and traces Japanese Buddhist astral practices through Chinese and Indo-Iranian transmission.
Mythology & symbolic world
Astral deities and ritual images carried religious functions as well as technical meanings. Kotyk documents the reception of imagery with Iranian precedents. This history is more complex than assigning each modern personality type to a Japanese animal or mansion.
Provenance: where the rules come from
The registry is a research gateway to named texts and traditions. Its equal nakshatra calculation is not presented as a complete reproduction of Chinese xiu or every Japanese lunar-mansion procedure.
How it is calculated
Choices that change the result: Equal nakshatras are not a validated replacement for every mansion tradition.
Inspect your calculated data →Uses & use cases
- Explore how calendrical learning travelled through Buddhist networks.
- Distinguish ritual scheduling, mansion classification and horoscope interpretation.
Interpretation methods
Identify what the source actually measures
First establish whether a text uses a daily mansion sequence, an astronomical mansion position or a full horoscope; apply its calendar and star tables before reading symbolic associations.
Two sources can list a similar mansion name yet assign a given date differently because one follows a day-count table and another a positional rule.
Concepts in this tradition
Follow a term for its definition, word origin, evidence and connected ideas.
Disagreements & limits
- Twenty-seven and twenty-eight mansion schemes require separate definitions.
- Historic Onmyodo is broader than a natal chart calculator.
- No personal Japanese mansion result is currently validated by this engine.
Sources & evidence
Practitioner sources describe their own systems. Historical and astronomical sources support different kinds of claims. Reading exercises are editorial teaching examples.
- Japanese Buddhist Astrology and Astral Magic — Jeffrey Kotyk, 2018 ↗original peer-reviewed research
- Tibetan calendar mathematics — Svante Janson, Uppsala University ↗scholarly mathematical research