When did humans realize that the Earth is a sphere? How did you meet?

It was in 1522 that humans began to recognize the Earth as a sphere. Magellan's circumnavigation of the globe not only opened up new routes, but also proved that the Earth was round through his expeditionary fleet.

It was recognized more than a thousand years ago that the Earth was a sphere, mainly through Magellan's fleet, which first circumnavigated.

Around the thirteenth and fourteenth centuries developed the Earth was a sphere. The Portuguese navigator Magellan believed that the Earth was a sphere, so he circumnavigated the globe and finally returned to the original point to prove that the Earth was a sphere.

People have come to realize that the earth is a sphere since the age of sailing, and when Magellan sailed, the ship was slowly revealed in people's field of vision in the sea, proving that the earth is a sphere.

With the development of human social productivity, science and technology, and navigational transportation, the scope of people's activities has gradually expanded, the field of vision has become broader, and the spherical concept of the earth has gradually formed. In particular, Magellan completed the first circumnavigation of the world by man, proving to people with irrefutable facts that the earth is round and the world's oceans are a whole.

The process of human understanding of the earth is that the earth is not a normal sphere, but an irregular sphere with slightly flattened poles and slightly bulging equators. However, it has been a long process to get this correct understanding.

In China, as early as the Zhou Dynasty more than 2,000 years ago, there was a kind of Gaitian theory that "the sky is round like a cover, and the place is like a chess game". With the development of production technology, the expansion of the scope of human activities, and the accumulation of various knowledge, people have finally discovered that there are some objective phenomena that cannot be explained by the intuitive and simple concepts of the early days. Practice forced people to revise their original misconceptions, and some people put forward the idea of arching the earth.

This gave rise to the "armillary theory". Zhang Heng, a famous scientist of the Han Dynasty, wrote in his "Notes on the Armillary Sphere": "The armillary sky is like a chicken, the celestial body is round like a projectile, the earth is like a chicken in the yellow, living alone, the sky is big and the earth is small."

There is water in the sky, and the sky envelops the earth, and the shell is yellow. Heaven and earth stand by air, carrying water and floating. ”

The cognitive process of human beings is a gradual process, limited by the conditions at that time, the understanding of the shape of the earth is not comprehensive, but it was also advanced at that time, so it is impossible to do things smoothly, and it is necessary to hold on.

It's actually a process of careful observation, good at asking questions, and diligent in thinking.

Magellan's circumnavigation of the globe made it known that the Earth was a sphere. Magellan's circumnavigation of the world is a major achievement in the history of world navigation, it was the Portuguese seafaring explorer Magellan led the expedition fleet of the world to set off on September 20, 1519, and successfully returned on September 6, 1522, which lasted 1,082 days. Magellan's successful circumnavigation of the globe not only opened new routes, but also proved that the earth is round and that the earth is a round sphere through the expeditions of his expeditionary fleet.

Earth is one of the eight planets in the solar system, the third planet in order from near to far, and it is also the terrestrial planet with the largest diameter, mass and density in the solar system, 100 million kilometers away from the sun. The Earth rotates from west to east while revolving around the Sun. Now 4.046 billion years old, it has a natural satellite, the Moon, which forms a celestial system, the Earth-Moon system.

It originated from the primordial solar nebula 4.6 billion years ago.

1. In the Zhou Dynasty more than 2,000 years ago, there was a kind of Gai Tianxin Liang Yu theory that the sky was round like a cover and the place was like a chess game.

2. Zhang Heng, a scientist in the Han Dynasty, put forward the theory of armillary heaven.

In 1522, a fleet led by the Portuguese Magellan sailed around the world, further confirming that the Earth was indeed a sphere.

4. The famous British physicist Isaac Newton proposed the law of gravitation in the 80s of the 17th century, and he started from this theory and proposed that the earth cannot be a positive sphere due to its rotation around its axis, but can only be an oblate sphere with compressed poles, envied by the equatorial bulge, and like an orange.

5. When the French astronomical Richer made astronomical observations in South America, he found that the pendulum clock oscillated only by the action of gravity on the ground, and the period of oscillation in Paris, France was different from that in South America. He believed that this was caused by the difference in gravity on the ground, and went on to explain the change in gravity on the ground.

In the 30s of the century, the Academy of Sciences in Paris was divided into two factions, so King Louis XIV of France sent two expeditions to measure the arc of the meridian again.

In the 50s of the century, the size and shape of the earth were accurately measured through technology, where the average equatorial radius of the earth is a kilometer.