RT @IoniaScience: Let’s dispel any flat-Earth myths. In this video Carl Sagan explains how Eratosthenes of …

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This content was posted on 9 Mar 23 by Lene Rachel Andersen on Twitter

RT @IoniaScience: Let’s dispel any flat-Earth myths.
In this video Carl Sagan explains how Eratosthenes of ancient Greece calculated the circumference of the Earth 2000 years ago.
I included an animation with the math/geometry in the next tweet for those interested. (1/2) https://t.co/FomTwK3UM1

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