Eternal India Encyclopedia

Eternal India encyclopedia

PERCEPTIONS

JYOTIRVIGNYAANA (ASTRONOMY)

Astronomy in India, like in other civili- sations, has very ancient origins. The earli- est records of astronomical thinking in India can be found among the Vedas dating back to earlier than the 1st millennium B.C. Sub- stantial progress was made in the 1st mil- lennium A.D. with the primary interest in the study of the motions of the sun and moon in order to develop a working calendar to determine the times for performing the various religious ceremonies and agricul- tural operations. For the ancient Indian, the sun was the most important heavenly object and its heavenly path was considered sacred. The moon's path was observed in relation to the 27 "nakshathras" (lunar mansions) or asterisms. It was found that the moon spends a day in each "nakshathra" and momentarily comes into a state of con- junction with the most conspicuous star in that group. Then the names of the lunar months, numbering 12, were given on the basis of the nakshathra on which the full moon occurred. These 12 lunar months total to about 354 days and sixty-two lunar months are approximately equal to sixty solar months. Thus every thirty months an extra month had to be added making that particular one a thirteen-month year. A very important feature of Indian as- tronomy is the cyclic concept of time. This was developed from the concept of 'yuga' or cycle. The 'Mahaayuga ' or the great cycle, is conceived as a period at the beginning of which all the planetary bodies are in con- junction. This period is given as 4,320,000

name a few — who improved upon the knowledge of astronomy in India. Gradu- ally, the interaction between the Indian as- tronomers and those from as far as Greece and Baghdad made very significant impact on the advancement of knowledge of that period. The 2nd millennium A.D. saw the intro- duction of some simple instruments like the water clock for the measurement of time, among others. A versatile instrument, the astrolabe, which was known to the Greeks, travelled to India along with Arab astron- omy. In the 18th century A.D., a major achievement in the usage of astronomical instruments of medieval origins was made by Maharaja Sawmi Jai Singh II of Jaipur, who erected huge observatories with large masonry structures for observing the celes- tial objects. Two of his observatories can be seen even today in Delhi and Jaipur under the exotic name of "Jantar Mantar" or the mysterious instruments. However, there are records to show that in 1689, a tele- scope was used for the first time on Indian soil to make stellar observations from Pon- dicherry, a coastal town in southern India. And the subject of astronomy in its new and modern form made inroads into India with the arrival of the Europeans about three centuries ago. Yet, even today many sections of Indian society continue to prac- tise the astronomically timed age - old re- ligious rituals of ancient origin sometimes meaningful and sometimes otherwise.

solar years which is then divided into four mundane ages or 'yugas' in the descending order of 4:3:2:1. The last one is named as "Kali Yuga" or the Iron Age through which the world is currently passing and is be- lieved to have started in 3102 B.C. Aryabhata, the great Indian astronomer and mathematician of the 5th century A.D., differed from the other astronomers of the time in saying that the earth was not stationary but rotated about its own axis. The ancient Indians were aware of the seven moving celestial objects — Sun, Moon, Mercury, Venus, Mars, Jupiter and Saturn which were generally termed as. planets since the belief was that the earth was the centre of the universe around which the planets move. To these seven Objects, two more were added — the demonic figures Rahu and Ketu, which are in fact the ascending and descending nodes of the moon, to facilitate the theories of the eclipses. The priestly astronomers of the era saw eclipses as caused by Rahu (the demon's head) devouring the sun or the moon. However, Aryabhata with his mathematical knowledge, could provide an explanation in terms of the sun being obscured by the moon and the shadow of the earth obscuring the moon. Great importance was placed in the accurate forecasting of the eclipses as religious rituals were observed during the eclipses. Even now, these rituals are practised in many parts of India. There were many other great scholars - Varahamihira, Bhaskara, Brahmagupta to

(G.S.D.B)