International Astronomy Day is an event, observed on different dates, every year. This year, it is being observed on April 21st. An opportunity for the common man to interact with those specialized in Astronomy.
The word ‘Astronomy’ is derived from the Greek word ‘Astronomous’ meaning ‘star arranging’.
Astronomy is a field India has excelled in. Deergatama is the first Astronomer in the Indian tradition. Dheerga means long and Tama is darkness. An Astronomer is the one who studies for long the darkness – the space.
The field of Astronomy is denoted by the term Jyotisha in India. The word Jyotisha comes from the word Jyoti, meaning to illumine. This body of knowledge called Jyotisha is about the astral bodies that emit light, Jyoti.
Ganita Jyotisha and Phalita Jyotisha
The word Jyotisha while being used for Astronomy is also used to denote Astrology.
Astrology is known as Phalita Jyotisha and Astronomy is called Ganita Jyotisha, a mathematical observational science. Astronomy is also known as Siddhantha Jyotisha, an exact science.
Astrology is a predictive field which deals only with the zodiac belt, Rashi belt of stars and the transit of the sun, moon and the five planets namely Mercury, Venus, Mars, Jupiter and Saturn within this belt and its probable impact on earth and earthlings. In contrast, astronomy deals with the whole sky and not just the zodiac belt. There is nothing predictive in astronomy. It is clearly an observational, mathematical science.
Scientific Aspects in Ganitha Jyotisha
The scientific aspects discussed in Indian Astronomy, Ganita Jyotisha include,
- Heliocentric view in Indian Astronomy
- Scientific naming of planets and stars
- Distances in space
- Measurement of astral bodies
Heliocentric Model-An Indicator of the advanced Indian Astronomy
The west had adopted the heliocentric model after Galileo proposed it, 400 years ago, and before that it was the geocentric model that was in vogue.
The Geocentric model
In contrast, the India texts pertaining to Ganitha Jyotisha, the Veda and other texts have all along been mentioning heliocentric model for many millennia.
The Heliocentric Model
Heliocentric comes from the Greek word Helios, meaning Sun. In this view, the sun is at the centre of everything in the sky. Ganitha Jyotisha, Astronomy with its inclination to accurate recordings has always held the helio-centric view point. This is clearly indicated in a shloka in Rig Veda, compiled over 5000 years ago.
The Shloka in Rig Veda
According to the above shloka, the moon which is the satellite of the earth revolves around its mother planet and follows it in its revolution around the sun.
This shloka clearly indicates that the people of this country had recorded the helio-centric model, 5000 years ago.
If we see the arrangements of idols in a Navagraha temple, it is always seen that the idol of sun is in the centre, surrounded by the idols of other planets.
Navagraha shrine with the idol of sun in centre
This again testifies that Indians always knew and followed the heliocentric model. They knew that all the planets revolved around the sun. Hence, the Solar System is called Surya Mallika, Surya meaning Sun.
‘Wonders of Indian Astronomy’
More on the Heliocentric Model and the other scientific aspects of Ganitha Jyotisha, Astronomy in our film, ‘Wonders of Indian Astronomy.’
Indian archaeologists and astrophysicists have discovered the world’s oldest record of a supernova at Burzahama in Kashmir, India.
This event identified as Supernova HB9 was visible in 3600 BCE.
Science Par Excellence
All these collectively show that Indian Jyotisha, Astronomy is a science par excellence that the ancient Indians had developed. Indian astronomers have written a series of astronomical treaties through millennia which form a rich contribution of Indians to the world of astronomical sciences.