True longitudes of planets

  • K. Ramasubramanian
  • M.S. Sriram
Part of the Sources and Studies in the History of Mathematics and Physical Sciences book series (SHMP)


The procedure for obtaining the madhyama-graha i.e. the mean longitude of a planet from the Ahargana, was explained in the previous chapter. Two corrections, namely manda-samskāra and śīghra-samskāra, have to be applied to the madhyama-graha to obtain the sphuta-graha or the true longitude of the planet. In these two samskāras, to be described later in this chapter, two angles, namely the manda-kendra (manda anomaly or mean anomaly) and the śīghra-kendra (śīghra-anomaly or anomaly of conjunction or solar anomaly) play important roles. In the above verse, the kendras and their sines and cosines (known as bāhus and kotis) pertaining to both the samskāras are dealt with. For this, two quantities, namely the ucca and the kendra, are introduced.


True Position Cube Root Fourth Quadrant Daily Motion Spherical Triangle 
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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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