education

Baloney Detection

August 09, 2018

More than 2,500 years ago, the first evidence for a spherical Earth was discovered by the Ancient Greeks. Around 500 BC, Pythagoras noted that the moon was a sphere and reasoned the Earth was as well. A few hundred years later, Greek mathematician Eratosthenes used simple geometry to estimate the circumference of Earth. He had surveyors measure the heights of shadows cast by sticks in the ground.