From: Thomas Hockey et al. (eds.). The Biographical Encyclopedia of Astronomers, Springer Reference. New York: Springer, 2007, p. 816


Courtesy of

http://dx.doi.org/10.1007/978-0-387-30400-7_993


Muñjāla

Narahari Achar


Alternate name

Mañjula


FlourishedDeccan, (India), possibly 900

Muñjāla was the author of a remarkable work, the Laghumānasa, which is an abridged version of a larger work called Bhanmānasa. Very little is known about the life of Muñjāla, except that he was a brāhmaa belonging to the Bhāradvājagotra, and that he lived in Deccan.

The Laghumānasa was very popular among the astronomers from Kerala, and it is mentioned by Bīrūnī. Parameśvara wrote a commentary on it, and quotations from it are found in the works of Bhāskaracārya and Munīśvara.

The Laghumānasa appears to be the first siddhāntic text to treat the precession of the equinoxes. Muñjāla gives the number of “ayana” revolutions to be 199,669 in a kalpa, and the “ayanāāśa” to be 6° 54' in 932 and the year of zero “ayanāāśa” as 522. Muñjāla was the first Indian astronomer to introduce corrections to the Moon's equation that account for what today is called evection. Muñjāla anticipates Bhāskaracārya in understanding that the sine and cosine are related in a way that we would express today by saying the derivative of a sine function is a cosine function.


Selected References

Bose, D. M., S. N. Sen, and B. V. Subbarayappa (1971). A Concise History of Science in India. New Delhi: Indian National Science Academy.

Dikshit, S. B. (1896). Bhāratīya Jyotisha. Poona, English translation by R. V. Vaidya. 2 pts. New Delhi: Government of India Press, Controller of Publications, 1969, 1981.

Muñjāla. Laghumānasa, edited with the commentary of Parameśvara by B. D. Āpaǭe. Ānandāśrama Sanskrit Series, 123. Poona; 1944; 2d ed. Poona, 1952. (There is also an English translation with notes by N. K. Majumdar, Calcutta, 1951.)

Pingree, David. Census of the Exact Sciences in Sanskrit. Series A. Vol. 4 (1981): pp. 435a–436a; Vol. 5 (1994): 312b. Philadelphia: American Philosophical Society.

Shukla, K. S. (1990). A Critical Study of the Laghumānasa of Mañjula. New Delhi: Indian National Science Academy.