Who discovered that the earth was round?

Question

A specific name of a specific person

Answer 1

Actually the ancient Greeks even manage to prove it.
It is said that the first person was Pythagoras mainly because in his theories he held that all celestial bodies are spherical.
But the firtst who provided observational evidence for the spherical Earth was Aristotle. He wrote that travelers going south see southern constellations rise higher above the horizon. This is only possible if their horizon is at an angle to northerners' horizon. Thus Earth's surface cannot be flat. Also, the border of the shadow of Earth on the Moon during the partial phase of a lunar eclipse is always circular, no matter how high the Moon is over the horizon. Only a sphere casts a circular shadow in every direction, whereas a circular disk casts an elliptical shadow in most directions.
(Aristotle, De caelo, 297b24-31
Aristotle, De caelo, 297b31-298a10 )
The Earth's circumference was measured around 240 BC by Eratosthenes the most important Greek astronomer.
Eratosthenes knew that in Syene (now Aswan), in Egypt, the Sun was directly overhead at the summer solstice, while he estimated that a shadow cast by the Sun at Alexandria was 1/50th of a circle. He estimated the distance from Syene to Alexandria as 5,000 stades, and estimated the Earth's circumference was 250,000 stades and a degree was 700 stades (implying a circumference of 252,000 stades). Eratosthenes used rough estimates and round numbers, but depending on the length of the stadion, his result is within a margin of between 2% and 20% of the actual circumference, 40,008 kilometres. Note that Eratosthenes could only measure the circumference of the Earth by assuming that the distance to the Sun is so great that the rays of sunlight are essentially parallel.
There you are! You have your answer!

Answer 2

Copernicus was imprisoned for proving that the earth was round, that the moon revolved around the Earth and that the earth revolved arond the Sun.

Although the Greek astronomer Aristarchus developed the same hypothesis more than 1500 years earlier, Copernicus was the first person to argue its merits in modern times. Pythagoras who first proposed that the Earth was round sometime around 500 B.C.

Around 350 BC, the great Aristotle declared that the Earth was a sphere (based on observations he made about which constellations you could see in the sky as you travelled further and further away from the equator) and during the next hundred years or so, Aristarchus and Eratosthenes actually measured the size of the Earth!

Answer 3

Aristotle theorised that the earth had to be round in order to cause lunar eclipses. Eratosthenes of Cyrene (276 BC - 194 BC) took measurements and estimated the circumference of the earth.
Columbus believed that the earth was round, but didn't prove it - he sailed out and back, not all the way round. Magellan did prove it by being able to sail right round the world.

Answer 4

Pythagorus is normally credited with the discovery, but there are Old Testament references to this which are older.

Isaiah 40:22 says that God looks down on "the circle of the earth." Viewed from space the earth does indeed appear as a circle since it is round.

Job 26:10 states, "He (God) drew a circular horizon on the face of the waters, At the boundary of light and darkness." This boundary between light and darkness is where morning and evening occur and is circular since the earth is round.

Job 26:7 also tells us that the earth floats in space stating that God "hangs the world on nothing." This pre-dates any other reference to this by centuries.

Answer 5

Pythagoras

Answer 6

Erastothenes, a Greek mathematician, in about 200 B.C.

Answer 7

It was Pythagoras (b. 570 BC) He found harmony in the universe and sought to explain it. He reasoned that Earth and the other planets must be spheres, since the most harmonious geometric form was a circle.

http://en.wikipedia.org/wiki/Round_earth

Answer 8

I'm not sure if any one person can be credited with this discovery, anymore than one person can be credited with the discovery of America, which was first populated shortly after the end of the last ice age. I suspect that the first people who realized that the earth was round were the early Portuguese traders, who sailed into the orient in pursuit of trade markets.

Answer 9

Some will say Galileo. But, the fact Earth was known to be round by the ancient Egyptians, Arabs, Chinese...thousands for years ago...

Answer 10

Some give it to Columbus and others say it was the Vikings.