They knew it was a sphere. An ancient Greek mathematician put up posts beside holes he dug so that he could measure the depth of the shadows at different times of the sun’s position. He used the data to estimate the circumference of the earth, and he was pretty close.
They knew it was a sphere. An ancient Greek mathematician put up posts beside holes he dug so that he could measure the depth of the shadows at different times of the sun’s position. He used the data to estimate the circumference of the earth, and he was pretty close.
Brilliant. I love physics!
Christopher Columbus didn't get the memo, I guess.