Who calculated the circumference of the Earth to a high degree of accuracy? Who calculated the circumference of the Earth to a high degree of accuracy? @History

Question

anonymous · Answer

Aristarchus, around 290 BCE.

anonymous · Answer

Wasn't it Eratosthenes?

anonymous · Answer

http://www.3villagecsd.k12.ny.us/wmhs/Departments/Math/OBrien/eros.html

anonymous · Answer

Eratosthenes was more accurate, yes. But Aristarchus measured the relative distance of the sun and moon from the earth, for which he needed to know the size of the earth. Eratosthenes gets credit for being closer in number, but Aristarchus wasn't off by much and he was 20 or 30 years previous.