IYA 2009 Featured Scientist of the Day - Eratosthenes of Cyrene

Today, we will talk about yet another remarkable individual in the history of Astronomy. It's none other than Eratosthenes of Cyrene. Since his outstanding measurements have been so lose to the precise data, Eratosthenes of Cyrene is credited with an acknowledgment of great accuracy.

Eratosthenes of Cyrene was a Greek astronomer, mathematician, poet, athlete, and geographer, thus remaking his name in different careers. Eratosthenes was the first one ever to precisely calculate the circumference of the Earth. It's highly remarkable that he was able to perform this kind of achievement with his great abilities in Mathematics during his era, where he lived from 276 BC to 194 BC. According to his calculations the circumference of the Earth was 24, 856 miles which would be 40,000 Km. As per the latest measurements with advanced technologies, the value of the miles is 24,860 which would be 40,007 Km when converted, leading to a great degree of precision.

This would give you a clear idea how an old age genius was able to perform outstanding calculations some 2250 years ago.


Eratosthenes also made several discoveries and inventions including a system of latitude and longitude, which was based for the development of modern day scale.

Among other achievements of Eratosthenes are the precise calculation of the tilt of the Earth's axis, and world map. It's believed that he might also have accurately calculated the distance from Sub to Earth leading to the concept of lead day.

It should also be mentioned that Eratosthenes was the founder of scientific chronology. He committed himself towards the course of fixing the dates of the chief literary and political events from the conquest of Troy.

Thus I dedicate the IYA 2009 Astronomy Sri Lanka blog today for the genius Eratosthenes of Cyrene in honor of his outstanding contribution towards astronomy.

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