Ancient Indian Astronomers and their contributions

Like all other culture and traditions, Indian astronomy was primarily related to religious practices. Greek ideas on astronomy influenced the Indian thinker as they got to know about it around the time of Alexander’s invasion. Texts like Yavanajatka and Romaka Siddhanta has clear and visible influence of the Indo-Greek culture. The Surya Siddhanta that we read today was found in the times of the Gupta Age is believed to have conceived its idea in this age. Since they mostly bred the oral tradition their content had survived and was received down by the great Aryabhata. The earliest trace of Indian astronomy can be found in the times of the Indus Valley Civilization. Indian Astronomy has reflected their influence in the Islamic Astronomy, European Astronomy and Chinese Astronomy. This article briefly points out the most important ancient Indian Astronomers along with the mention of their contributions briefly.

• The earliest evidence of the Indian Astronomy (and also astrology) is the Vedanta Jyotisa written by Lagadha which deals with the six kinds of auxiliary disciplines based on Hinduism. It generally deals with the schedules of social timings and other astronomical valuations for various religious events. This can be attributed as the first written detail of the seasonal cycle and time with inclusions of the solar and lunar months along with the mention of the leap month. Other fine details of eclipses, twenty seven constellations, seven planets and twelve zodiac signs were also mentioned.

• The second and perhaps the most important name in the Indian astronomy is of Aryabhata who had a major effect on the other astronomers. The Islamic astronomy was greatly influenced by his works like Aryabhatiya and Aryabhatasiddhanta. He was majorly a mathematician as well as an astronomer who explicitly discussed the rotation of the earth on its axis, the spherical shape of the earth, its circumference being of 24,835 miles and also that the moon shines because of the reflection of the sunlight on it. Many of his works of great significance are believed to be lost.

• Keeping to the track of the timeline, Brahmagupta, another Indian astronomer and mathematician falls on number three. Brahmasphuta-siddhanta and Khandakhadyaka are two of his works. Brahmasphuta-siddhanta revolves around both astronomy and mathematics. This was also translated in Bagdad into Arabic and influenced on the Islamic philosophies. He also gave the theory that all bodies consisting of mass are attracted towards the earth.

• Varahamihira was an educated scholar with profound knowledge in astronomy and mathematics who was well versed not only in Indian astronomy but also in the Egyptian, Greek and Roman philosophies. Pancasiddhantika is his work that records concise yet detail knowledge that he had gained from these philosophies.

• Bhaskara is the author of Mahabhaskariya, Aryabhatiyabhasya (commentary on Aryabhata’s work Aryabhatiya) and Laghubhaskariya. His works focuses on the longitudes of planets, conjunctions caused amongst planets and stars, solar eclipses and lunar eclipses and the various phases that the moon goes through.

• Lalla, Bhaskara the second, Sripati, Mahendra Suri, Nilakanthan Somayaji and Acyuta Pisarati are other notable astronomers and mathematician.