Indian Astronomy begins with the Vedic Age as Jyotisa, one of the six Vedangas. The tithis and nakshatras and the lunar months belong to this era. Astronomy evolved in the age of the Eighteen Siddhaanthas, with the adoption of the zodiac, and other interactions with Babylonian, Greek and Roman astronomy. Indian astronomy is deeply linked with astrology, religion, rituals, the development of various calendars and mathematics. The emphasis of the lecture will be on the last two aspects.
A parallel tract of Buddhist and Jain astronomy and astrology also existed. The great revolutionary of Indian Astronomy was Aryabhata, whose ideas led to a scientific and scholarly schism in the discourse on Astronomy that was settled only with advent of the telescope and European discoveries that followed it. Other notable astronomers were Varaha Mihira, BrahmaGupta, Bhaskara Acharya, Madhava, Paramesvara and Nilakanta Somayyaji. Some challenged orthodoxy, others defended it. All of them made significant contributions to mathematics, either original or corrective; and some innovated or improved instrumentation. Some of their accomplishments will be highlighted.
The movement of planets, stars, the sun, the moon, constellations, eclipses, several celestial cycles, led to the development of several calendric systems - solar, lunar, zodiacal, stellar, sidereal etc. - that are still in use today. Measurements of astronomical time like yuga, ahargana, ayana; distances like yojana; the use of an Indian Meridian along Mount Meru & Ujjain, long centuries before the Greenwich Meridian; and the divisions of time like muhurtha, nadi and vinadi will be discussed.
Also of interest is the continuity of guru-shishya paramapara, especially in the Kerala school of astronomy; and the continental spread of knowledge, scholarship and information exchange.