Ancient Indian Astronomy Geometry and Mathematics

Astronomy, Geometry and Mathematics

Ancient indian astronomy was a discipline associated with study of vedas dating 2000 BCE or earlier. Astronomical principles were borrowed to explain matters pertaining to astrology. However science of Astronomy continued to develop independently, key to advancements in Astronomy was development of geometry and mathematics.

Vedanga Jyotisha is one of the earliest known Indian text on Astronomy (1200 BCE), it includes details about the sun, moon, stars and the lunisolar calendar system. The Shubla Sutras written around 1000 BCE was dedicated to giving instructions on fire altar construction. The Subla Sutra discusses advanced mathematics like pythagorean theorem,  it gives many examples of pythagorean triplets to explain the concept. The Subla Sutra also uses other advanced geometry and mathematical concepts to explain construction. A Formulae for determining the square root of number two is described in detail, the value derived is accurate up to 5 decimal points from the true value.

In 500 AD, Aryabhata presented a astronomical and mathematical theories in which the Earth was taken to be spinning on its axis. Aryabhata also wrote that 1,582,237,500 rotations of the Earth equal 57,753,336 lunar orbits. This is an extremely accurate ratio, perhaps the oldest astronomical constant calculated to such accuracy. Brahmagupta (598-668 CE) was the head of the astronomical observatory at Ujjain and during his tenure there wrote a text on astronomy, the Brahmasphuta Siddhanta. Bhaskara (1114-1185 CE) was the head of the astronomical observatory at Ujjain, continuing the mathematical tradition of Brahmagupta. He wrote the Siddhanta Siromani which consists of two parts: Gola Dhyaya (Sphere) and Graha Ganita (Mathematics of the planets).

Ancient Indians used words to express numbers, for instance the word “Bhuj” meaning arms was used to denote the number two (since humans have two arms). But words did not allow mathematical calculations, so around 10 BCE words were replaced by symbols to represent numbers.  Before the Indians the Babylonians had a two single symbols to represent numbers, but the applications of this was limited.  The Indian system of 9 single digits to represent numbers was more convenient and accurate. But the most significant contribution of Ancient India was the last symbol of this ingenious numerical system and that is Zero.  The symbol stood for the sanskrit word Shunya meaning nothing. Introduction of this symbol as a concept to the numerical system was a landslide moment in history of mathematical computations. The invention of Zero has been heralded as one of the greatest in human history, it is what allowed modern mathematicians and physicists make advancements, without it there would be no binary system and no computers.  This 10 digit system given to us by Ancient Indians is what we use today.