Drigganita

Drigganita (दृग्गणित; IAST: dṛggaṇita, from dṛk-gaṇita, "sight-calculation"), also called the Drik system,[1] is a system of astronomical computations followed by several traditional astronomers, astrologers and almanac makers in India. In this system the computations are performed using certain basic constants derived from observations of astronomical phenomena. The almanacs computed using the methods of Drigganita are referred to as Drigganita Panchangas.

The Drigganita system is in contrast to the method followed by some other almanac makers who use the values given in the ancient astronomical treatise known by the name Surya Siddhanta. The almanacs computed using this treatise are known as Sydhantic Panchangas. They are also known as Vakya Panchangas.[2]

In the history of astronomy in India, two different Drigganita systems have been introduced at two different points of time and at two different geographical locations. The first system was introduced by the Kerala astronomer-mathematicians Parameshvara (1380-1460) and Damodara in the fifteenth century. Incidentally, Drigganita is also the title of a book authored by Parameshvara through which the Drik system was promulgated.[1][3] In the nineteenth century, a second Drigganita system was introduced by Chinthamani Ragoonatha Chary (1822 – 5 February 1880) an Indian astronomer attached to the then Madras Observatory.[4][5]

  1. ^ a b K. V. Sarma (1972). A History of the Kerala School of Hindu Astronomy (PDF). Vishveshvarananda Institute of Sanskrit and indological Studies, Panjab University, Hoshiarpur. pp. 9–10. Retrieved 18 February 2016.
  2. ^ N. Narasimha Rao (February 2005). Basics of Panchangam (PDF). Shri Vijayadhwaja Jnanapeeta (Regd.) Shri Pejavara Mutt. Retrieved 18 February 2016.
  3. ^ Critically edited with an Introduction by K. V. Sarma (1963). Drigganita. Vishveshvarananda Institute of Sanskrit and indological Studies, Panjab University, Hoshiarpur. {{cite book}}: |last1= has generic name (help)
  4. ^ Venkateswaran T. V. "Chinthamani Ragoonathachary and Secularization of Time During the Late Nineteenth Century Madras Presidency" (PDF). Proceeding No 521 of March 26, 1878, Fr St George. Retrieved 30 May 2013.
  5. ^ B. S. Shylaja (10 May 2009). "Chintamani Ragoonathachari and Contemporary Indian Astronomy". Current Science. 96 (9): 1273. Retrieved 18 February 2016.