Bhāskara I

Bhāskara I (Not the author of Līlāvatī) was a famous astronomer during 7th Century CE. Bhāskara I belong to Aśmaka (country lying between the rivers Godāvarī and Narmadā) country. The earliest commentary on Āryabhatīya is found in Āryabhaṭīya-bhāṣya of Bhāskara I. Bhāṣya in Samskrit means ‘a commentary’. The other contributions of Bhāskara I was on Mahābhāskarīya and Laghubhāskarīya on the astronomy.

Mahābhāskarīya deals with the following topics.


 * Mean positions of the planets
 * True positions and true velocities of the planets and their applications
 * Directions, time and place
 * Computation and graphical representation of the eclipses
 * Heliacal and diurnal risings of the Moon and the elevation of the lunar horns
 * Heliacal rising and the conjunction of the planets
 * Conjunction of a planet with a star

The language of Mahābhāskarīya is simple and is meant to be easily understandable.

Mahābhāskarīya is the only available work on Hindu Astronomy which explains the motion of the planets with the help of the epicyclic theory and eccentric theory.

Laghubhāskarīya is a revised and abridged edition of Mahābhāskarīya. It was written for younger and immature students of astronomy. Laghubhāskarīya deals with the following topics.


 * Chapter 1 - Calculation of the mean longitudes
 * Chapter 2 - Calculation of the true longitudes, the Pañcāṅg
 * Chapter 3 - Directions, place and time
 * Chapter 4 - Eclipse of the moon
 * Chapter 5 Eclipse of the sun
 * Chapter 6 - Heliacal visibility and phases of the moon, elevation of the Moon's horns, and moonrise
 * Chapter 7 - Heliacal visibility and conjunction, in longitude, of the star - planets (Mars etc.)
 * Chapter 8 - Conjunction of planets with the stars

Bhāskara I's commentary on Āryabhaṭīya is in two parts which are given different names. The commentary on the Daśagītikā-sūtra (which forms the first chapter of Āryabhaṭīya) is called Daśagītikā-sūtra-vyākhyā and commentary on the remaining three chapters is called Āryabhaṭa-tantra-bhāsya.

In the Daśagītikā-sūtra-vyākhyā, the commentary on each sūtra consists of


 * An introductory sentence indicating in brief the subject matter mentioned in the sūtra
 * Statement of the sūtra
 * Pada-ccheda ː seperation of words present in the sūtra
 * Interpretation of the text and explanation of the contents.