The true position of the Earth’s shadow is said to be the sum of the true position of the Sun and a half-circle (180 degrees). Having determined the position of the Moon and the [Earth’s] shadow either at sunrise or at sunset, whichever is closer [to the conjunction], the time of their conjunction may be determined. If [the longitude of] the Moon is greater then the conjunction is over, and if it is less then it is yet to occur. Their difference [in longitude] multiplied by 60 and divided by their difference in daily motion [gives] the time for conjunction (the yogakāla) expressed in ghatīs etc. that has already elapsed or is yet to elapse respectively.


Solar Eclipse Actual Distance Daily Motion Vertical Circle Angular Diameter 


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© Hindustan Book Agency 2011

Authors and Affiliations

  1. 1.Department of Humanities and Social Sciences, IIT BombayCell for Indian Science and Technology in SanskritPowaiIndia
  2. 2.Department of Theoretical PhysicsUniversity of MadrasChennaiIndia

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