About the Flat Earth

I grew up with the idea that until Galileo Europeans believed the Earth was flat. I was quite surprised that this is a big misconception, I didn't even realize that the Earth had been circumnavigated almost 100 years earlier.

Many ancient cultures believed in a flat Earth, but the ancient Greeks (Pythagorean philosophers, around the 6th century BC) already imagined a spherical Earth. Later, Eratosthenes was the first known person to have calculated the circumference of the Earth, with a remarkable accuracy for that time (I will describe in an other post how he did this without even leaving Egypt).

The spherical Earth theory was maintained by Aristotle, Ptolemy, and finally Johanes de Sacrobosco. He was a scholar, a monk and astronomer in Paris and wrote a short astronomy textbook in the year 1224, Tractatus de Sphaera, which was widely publicized. That book gave ample evidence of the spherical shape of the Earth. It was the reference book for astronomy until the 16th century AD.

A page from Tractatus de Shpaera, about the spherical shape of the Earth

But nowadays, many people assume that until the 15th or 17th century people in Europe believed the Earth was flat. In 1996 there was an advertisement on German TV, about a perfume called "Galileo":

A voice is saying "Die Erde ist eine Scheibe, Galileo!" (The earth is a disc, Galileo!), and he answers "Nein!" (No!). This is so absolutely wrong, as no one at that time thought the Earth should be flat! The problem Galileo had was that he placed the sun in the center of the universe instead of the Earth. Because until then it was largely assumed (since Aristotle) that the Earth was located in the center of the universe, endorsed by the church, fixed and immovable (Psalm 93(92)) and that everything in the heaven was turning around it.

Galileo publicized his first observations in 1610, that was even way after Christopher Columbus's first voyage in 1492 (and stumbled on America while he wanted to go to Japan). If people really believed the Earth was flat, he would never have done that trip. And what about Magellan? His crew circumnavigated the Earth (departed in the year 1519 and came back in 1522), he has unfortunately been killed in the Philippines. So, in Europe it was common knowledge that the Earth wasn't flat during the time of Galileo.

Besides, the oldest still existing terrestrial globe is from 1492. As America wasn't discovered yet (Christoph Columbus did return in 1493 and believed he were in India - that's why he called the people "Indios"), there is no such continent on it.

Martin Behaim's Erdapfel, 1492

Well, I forgot to mention the Flat Earth Society, descending directly of the Universal Zetetic Society. They still exist today, but should I even mention them?