How did Ferdinand Magellan figure out that the world was round?

Answer 1

Among the ancient Greeks, Homer thought the world to be flat. In contrast, Pythagoras postulated that the earth was round. A century later, Aristotle sided with the theory of the roundness of the earth.

Leave it to the clever Greek investigator Eratosthenes to bring it all together with a calculation (and a remarkably accurate one!) about the diameter of the earth, and also the inclination of its axis of rotation to its orbital plane about the sun.

Centuries later, independent work was done by Muslims as Europe descended into the Dark Ages. By the 9th century, many Muslim scholars took it for granted that the Earth was a sphere. The proof, said astronomer Ibn Hazm, "is that the Sun is always vertical to a particular spot on Earth". It was 500 years before that realisation dawned on Galileo. The calculations of Muslim astronomers were so accurate that in the 9th century they reckoned the Earth's circumference to be 40,253.4km --less than 200 km out. Later Europeans mistakenly attribute the work for Nicolaus Copernicus.

Edited just correction : with all respect to the one who answered the question, the Europeans did not thought that Copernicus discovred the Earth's Circumference mistakenly , in fact it he stole it and add it to his books is if it was his own work.

Answer 2

he sailed completely around it, by not finding an edge to fall off, he proved definitively it was round

Answer 3

Several people before Magellan discovered the Earth is round including Christopher Columbus. Also, Magellan and most of his original crew died before circumnavigating the globe.

Answer 4

He went all the way around the world until he came to where he left off.

Answer 5

He sailed around the world and proved to everyone that the earth is a spherical shape not flat