Sources
These are the references named in our code and data. Where a classical rule applies, it is cited. Where books or sites disagree, the method page says which way we go.
Updated 2026-11-10
Data and software
Place names, states, latitude and longitude. Licence: CC BY 4.0.
Positions of the Sun, Moon and planets.
The 14 by 14 yoni table.
Constants of the Lahiri ayanamsa, used to cross-check.
The vashya table, as published there.
Astronomy
Indian Calendar Reform Committee, Indian Astronomical Ephemeris
The definition of the Lahiri (Chitrapaksha) ayanamsa.
Lieske, 1977, IAU 1976 precession
The precession terms in the ayanamsa formula.
Jean Meeus, Astronomical Algorithms, 2nd edition, equation 47.7
The mean lunar node for Rahu and Ketu.
Classical texts
Muhurta Chintamani, Vivaha prakarana
Vashya groups (6.23), Tara (6.24), Bhakoot parihar (6.30 to 6.31), Nadi parihar (6.33), and the gana, yoni and nadi of each nakshatra.
Jyotirnibandha
The direction of the Gana table and the Nadi parihar rules.
Piyushadhara, commentary on Muhurta Chintamani
Nadi parihar by charan, and Gana parihar by friendly sign lords.
Brihat Parashara Hora Shastra, chapters 3 and 26
The natural friendships of the planets, and Jupiter's aspect.
Muhurta Martanda
Mars in its own sign as a Manglik parihar.
Avakahada chakra
The 108 syllables that tie a name to a nakshatra charan.
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