Sidereal against tropical

The gap between the sidereal rashis and the tropical signs is the ayanamsha, the accumulated difference between the two zodiacs due to the precession of the equinoxes, and it is the single largest technical difference between Indian and Western astrology. A person born under one tropical sign is often under the previous sidereal one.

The atlas gives each rashi its ruler, element, quality and significations, and notes its relation to the corresponding Western sign. The grahas that rule the rashis, and the divisional vargas built from them, are treated in their own categories.