What is the difference between Indian and western astrology?
Well, There is difference in calculation of position of planets in signs. Indian system of astrology considers fixed zodiac and the same for western astrology is movable. Actually earth takes 365 days 6 hours 9 minutes and 9 seconds to complete one cycle of revolving around the earth. This period is also called sidereal year. Sidereal year is approx 20 minutes longer then tropical year. Western astrology uses tropical year. This difference of 20 minutes is equivalent to 50.24 seconds of celestial longitude. This difference increases every year by same value. Therefore first point of Aries actually recedes by a value of approx 50.24 celestial longitudes every year. It takes about 26000 years for the two points to match again. Therefore if you see sun in Scorpio in western birth chart, it may appear in Libra in Indian system of astrology.
