Division and zodiac sign (Rasis )of Astrology______
1__siddhantas based astrology:___in this calculation of planets from the beginning (kalpa )is considered.
2__Tantra based astrology:____in this calculation of planets from Kaliyuga comes under tantra granths.
3:____karana based astrology__in this type calculation of planets from the beginning of Saka considered.
mostly Indian Astrologer follows siddhanta astrology based on sun
( Surya siddhanta) consisting Aryabhatta mathematical calculations. The earth is in approx round shape (360 degree ), if we divide it by12 (Rasis )each rasi comes on 30 degree means any planet posited in any rasi can’t be more than 30 degree. every day each zodiac sign (Rasi) also rises in the East in the morning in line with the sun sigh eg_if sun enters the sign Aries on Apr 14, the zodiac sign Aries will also rise at the same time in the horizon that day and will continue for two hours, then second rasi Taurus will rise in horizon for two hours like so on the sun completes rotation on 12 zodiac sign in a day. The sun stays one month on one rasi and completes 12 zodiac signs in12 months .
This is responsible for asendent or the rising sun or lagna.it will be the first house of birth chart.
There are twelve zodiac signs or Rasis in astrology having its own Lord,some lord may repeat two Rasis also. Rasis are_
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