Aryabhata

=Introduction=

Aryabhata is easily considered the father of Pi, having worked on the number we concider today. He was the first in a long line of mathematicians and astronomers. He was also called Aryabhata I or Aryabhata the Elder. He was born during the golden ages of India. It is unknown exactly where he was born, but he was most likely born near Ashmaka or Kusumpura in 476 AD. "Arya" is a term of respect while "Bhata" is a last name commonly used by traders.

=Contributions=

Aryabhata made a large impact in both Mathematics and Astronomy. Some of his mathematical accomplishments include using zero in a place value system as a holder for the power of ten. Although he didn't use the symbol we know today, it was still present in his work. He worked in Sanskrit, an Indo-Aryan language common during his time. He also made the approximate for Pi that is close to what we use today. In the Aryabhatiyam he states that:

//"Add four to 100, multiply by eight and then add 62,000. By this rule the circumference of a circle of diameter 20,000 can be approached."//

When it's calculated out, the ratio is 3.1416. Aryabhata also worked on the Sine tables.

In Astronomy, he made the suggestion that the Earth rotates on an axis. He also was one of the first to state that the light from the moon and planets was just a reflection of the sun. It was believed that when an eclipse happened it was from Rahu, a mythological snake which was believe to swallow the moon, or Ketu, a Naga-like celestial being, eating the moon or sun. Another Hindu belief was that Rahu and Ketu weren’t mythological and celestial beings, but invisible planets. However, Aryabhata explanted that this was not the case and that it was, instead, that a shadow was being cast across the moon or sun. Aryabhata also calculated out the circumference of the Earth. His calculation, which was 24,853 miles, is only 0.2% smaller then the actually circumference, which is 24.902 miles.

Another of his achievements in the field of Astronomy was his calculation of sidereal time. Sidereal time is the calculation of Earth’s rotation based of fixed stars. He said that it was 23 hours 56 minutes and 4.1 seconds. The accepted modern number is 23 hours 56 minutes and 4.091 seconds. Using his calculation, Aryabhata said that the length of a year was 365 days 6 hours 12 minutes and 30 seconds; this is just 3 minutes off the actually length. His computation is considered the most accurate for the time.

=Legeacy=

Aryabhata’s works influenced many and were translated into Arabic during the Islamic golden age and then later into Latin by Gerard of Cremona. However, when it translated it, he misinterpreted jiba to be the Arabic word jaib which translates to ‘a fold in a garment’, which in Latin would be L. sinus. This is how we got the modern name Sine. Aryabhata’s tables became the basis for Trigonometry. His computations evolving time have become the basis for many calendars in the Middle East and India. In India is it still used for the fixing of Panchanga, also known as the Hindu calendar. A modified version of his calendar is still the national calendars of Iran and Afghanistan. His computations formed the base for the Jalali calendar. They required the dates be determined by the solar transit. Although it is much harder to figure out the dates, it has lower seasonal errors then the Gregorian calendar that we are accustomed to. Aryabhata’s discoveries helped build the foundation for our modern Trigonometry and helped change the face of Astronomy. To honor him, India named their first satellite was named in his honor. A crater on the moon’s surface also bears his name.