Ayanamsa: tropical and sidereal
Western astrology measures the zodiac from the spring equinox (tropical); the Indian tradition measures it from the fixed stars (sidereal). The gap between the two is the ayanamsa.
Today's figure Live
Ayanamsa now (Lahiri (calibrated)): 24°14'13". Sun: tropical 194°22'56" (Tula (Libra)), sidereal 170°08'42" (Kanya (Virgo)).
How it works
The equinox slowly moves backwards against the stars (precession of the equinoxes), by about 50 seconds of arc a year, so the gap grows by roughly one degree every 72 years.
Sidereal longitude = tropical longitude − ayanamsa. This site uses the Lahiri (Chitrapaksha) ayanamsa by default, the one adopted by the Government of India's Calendar Reform Committee: about 23°51′ on 1 January 2000, carried forward with the IAU 2006 precession and nutation. Other ayanamsas (Raman, Krishnamurti, True Chitra) can be chosen in the calculation profile.
Rashis, nakshatras, yogas and Sankrantis use sidereal positions and depend on the ayanamsa; tithis and karanas depend only on the Moon–Sun angle and do not.
In this site's engine
The ayanamsa is the profile's value at the reference epoch, carried forward with the IAU 2006 general precession, plus nutation in longitude so that it matches the apparent positions.
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Related terms
Live values for the selected place, calculated when this page was loaded.
Traditions may vary by region and Panchang convention. Times are shown for the selected place, time zone and calculation profile.