Aryabhata was a mathematician and astronomer, wrote a book in Sanskrit known as the Aryabhatiyam.

His contribution are:

• He stated that day and night were caused by the rotation of the earth on its axis, even though it seems as if the sun is rising and setting every day.
• He developed a scientific explanation for eclipses as well.
• He also found a way of calculating the circumference of a circle, which is nearly as accurate as the formula we use today