# sagan earthday math science otd onthisday saltpinch

Carl & No, the picture is *not* Sagan & Eratosthenes….but it could have been!

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2022-01-28

Eratosthenes was a Greek polymath & chief librarian of the Library of Alexandria. He was the first person who calculated the circumference of the Earth. In addition, he believed that on this day, 24th of April, in 1183 BC the city of Troy fell and the legendary war ended.

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2020-04-24

Happy More than 2000 years ago, the Greek mathematician Eratosthenes found a way to measure the radius of Earth just using shadows, angles, and simple geometry: https://t.co/WhhzNXC4Cr

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2020-04-22

DID YOU KNOW: Over 2000 years ago, Eratosthenes estimated the Earth's circumference without ever leaving Egypt, and he was accurate within 2%.

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2020-01-14

KISAH ERATOSTHENES: PENEMU KELILING BUMI PERTAMA

--- A THREAD

Eratosthenes mampu mengukur keliling bumi pada 2.200 tahun yg lalu secara cukup presisi dg menggunakan tongkat, kaki, & otak saja! Dia membuktikan bahwa bumi “harus” bulat agar seluruh fenomena dapat terjawab. How?

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2020-01-12

According to Eratosthenes, Chron. FGH 241 F 1d, the Greeks captured and burned Troy in 1184BC

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2017-06-11