Your science teacher may have told you that Copernicus discovered the Earth was round. However, the Greeks used the North Star to make the same discovery!
The Greeks had it figured out that the earth was round. How did they manage it? Learn more on this Moment of Science.
Even the ancient Greeks used performance enhancers in the form of leaden and stone hand weights called halteres, which weighed between four and twenty pounds. The proof is plain to see on many ancient Greek urns depicting Olympic athletes clutching these objects as they compete in the long jump.