How The Ancient Greek Knew The Earth Was Round Over 2,000 Years Ago

Carl Sagan explains how the ancient Greek knew the Earth was round and how they calculated its circumference over 2,000 years ago.



How The Ancient Greek Knew The Earth Was Round Over 2,000 Years Ago

Carl Sagan explains how the ancient Greek knew the Earth was round and how they calculated its circumference over 2,000 years ago.