Pythagoras Theorem which states that “ in a right angled triangle the sum of the squares of the two sides are equal to the square of the hypotenuse”. Pythagoras of Samos was a Greek mathematician who lived from 560 B.C to480 B.C. You will be happy to learn that the great Indian astronomer Aryabhata has propounded this theory independently. Aryabhata is the first great landmark in the history of Mathematics in India. He wrote “Aryabhatiya “ when he was 23 years and it consists of thirty-three couplets of bare rules so condensed as to be nearly impossible to interpret. Little is known about his life except that he was born in Pataliputra and that his ideas were bitterly opposed by the orthodox. He was the first to espouse the theory that the Earth was spherical and revolved round the Sun. People then believed that the Earth was flat and the Sun was revolving round it. Aryabhata calculated the length of the day to be 23 hours—56 minutes—4.1 seconds. The modern scientists with the help of computers declared the day to have 23 hours—56 minutes and 4.091 seconds. Aryabhata also gave a value of 3.1416 to “Pi” which today is defined to be 3.14159.He does not explain how he found this accurate value. In the “Aryabhatiya “ he wrote— "Add four to one hundred, multiply by eight and then add sixty-two thousand. The result is approximately the circumference of a circle of diameter twenty thousand. By this rule the relation of the circumference to diameter is given." In other words , Pi =62832 / 20000 =3.1416, correct to four rounded-off decimal places. For the first time in the history of mathematics Aryabhata defined squares, triangles, rectangles, circles and cubes in mathematical terms. Aryabhata discussed subjects such as quadratic equations, sines and announced the sphericity of the Earth, its diurnal revolution on its axis. He declared as early as sixth century A.D.590-- in anticipation of renaissance science, “The sphere of the stars is stationary and the Earth by its revolution, produces the daily rising and setting of planets and stars.”. A crater on the moon is named after Aryabhata. The Indian Government named its first satellite Aryabhata in his honour. It was launched in 1975. If you want to see an impressive statue of Aryabhata go to IUCCA –in Pune. This Institute is dealing with Astrophysics and its Godfather is Jayant Narlikar Jayasala42