Oz Blog News Commentary

of the importance of measurements...

September 5, 2021 - 11:22 -- Admin





















Aswan, at approximately 24 degrees north latitude, lies very near the Tropic of Cancer (23°27′ N), and at this latitude, near the time of the summer solstice, the Sun is (roughly) 90 degrees above the horizon at noon...



Around 245 BC, when Eratosthenes was in his 30s, he was working as a librarian in the famous Library of Alexandria in Egypt.

He read about a water well in the city of Syene (modern-day Aswan in southern Egypt).

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