Eratosthenes of Cyrene (Greek Ἐρατοσθένης; 276 BCE - 194 BCE) was a Greek mathematician, poet, athlete, geographer and astronomer. His contemporaries nicknamed him "beta" (Greek for "number two") because he supposedly proved himself to be the second in the ancient Mediterranean region in many fields. He is noted for devising a system of latitude and longitude, and for being the first known person to have calculated the… (More on Eratosthenes)