More than 2,200 Years Ago, an Ancient Greek Scholar Calculated the Earth's Circumference with a Stick and the Sun

More than 2,200 years ago, an ancient Greek scholar calculated the Earth's circumference with a stick and the Sun

Science News: More than 2,200 years before satellites, GPS and space missions revealed the Earth's true size, an ancient Greek scholar calculated the planet's circu.

The ancient Greeks calculated the circumference of the Earth around 240 BCE, using nothing more than a stick, the sun, and the distance between two Egyptian cities

Some time around 240 BCE, a librarian in Alexandria worked out the size of the planet from the length of a single shadow. His only equipment was an upright stick, a clear day, and a figure for the distance between two Egyptian cities. Eratosthenes of Cyrene ran the Library of Alexandria and had a habit of appearing in several fields at once. His reckoning of the Earth’s circumference is the one everybody remembers. What he did was real and ingen…