The Man Who Accurately Estimated the Circumference of the Earth Over 2,000 Years Ago
Today I found out about a man who fairly accurately estimated the circumference of the Earth well over 2,000 years ago: Eratosthenes of Cyrene. Born around 276 B.C. in Cyrene, Libya, Eratosthenes soon became one of the most famous mathematicians of his time. He is best known for making the first recorded measurement of the Earth’s circumference, which was also remarkably accurate. (And, yes, people at that point had known for some time that the world wasn’t flat, contrary to popular belief.) Eratosthenes was able to accomplish this in part because of his education in Athens.