when did we discover that the earth was round?

Question

what year how many years ago?

Answer 1

Different cultures around the world have known that the earh was round for thousands of years. In Ancient Greece, the philosopher and mathematician Eratosthenes was actually able to calculate the circumference of the earth, by measuring the lengths of the shadows cast by poles sticking out of the ground... one in Alexandria, Egypt, and the other in Syene, Egypt. he was correct to within a few percent of the true value.

Another reason the ancient Greeks knew the earth was round, was because they noticed that when ancient ships sailed out to sea, the last part of the ship that disappeared beneath the horizon was the tip of its mast.

Other cultures, such as the Inuits (or Eskimos, if you want to be politically incorrect), also knew the Earth was round by analogy with the moon and the sun, which they believed were places similar to the earth.

The persistent myth that Christopher Columbus "proved" that the earth was round is completely false, not only because humans already knew the earth was round thousands of years before 1492. Christopher Columbus landed in America, and did not circumnavigate the globe... so how would sailing across the Atlantic Ocean prove that the earth was round?

Answer 2

i do no longer keep in mind the call yet i've got confidence a guy from historical Egypt proved that the earth became around or maybe have been given a incredibly precise estimate of the earth's diameter. It in touch determining the size of particular construction's shadows at a particular time on a particular day while the sunlight became at as quickly as above a particular water properly. via geometry, the shadows desperate the angles, the area between the properly and the two homes (that have been many many miles faraway from one yet another). undecided precisely while this befell. The Mayans have been mind-blowing astronomers and stepped forward a calendar this is precise interior of ~ 2 seconds a pair thousand years later. of path the Isaiah did no longer have lots risk of understanding what the Mayans knew.

Answer 3

I heard there's a book about how things were really discovered, and knowlege of the earth being round was already common public knowledge before that one guy, descartes found out about it. Technically he turned an hypothesis into a theory I guess. When the first pictures of earth being round were taken that's when the theory turned into fact or something.

Answer 4

Pythagoras determined the earth was round in 570 BC

Answer 5

Christopher Columbus in 1492 confirmed it was round
but this article says people knew 2500 years ago & forgot
http://www.gma.org/space1/nav.map.html

Answer 6

Shortly after 1492... after that Christopher Columbus thing you know...

Answer 7

2 hrs ago

Answer 8

earth is not round, but it is elliptical in shape.