What is the process of human understanding of the shape of the earth? How do the sun and the earth rotate?

The shape of the earth is roughly ellipsoidal, with a slight bulge near the equator. The earth is the only celestial body known to breed and support life. The history of the earth is very long. How do the sun and the earth rotate? Is the earth an inner planet or an outer planet? If you want to learn more about this knowledge, please open the following content and hope it will help you.

Contents of this article

1. Humans’ understanding of the shape of the Earth

2. How do the sun and the earth rotate?

3. Is the Earth an inner planet or an outer planet?

Humans' understanding of the shape of the earth

Human beings' understanding of the shape of the earth has gone through a long process of imagination, speculation, verification, witnessing, and measurement. The ancients believed that the earth was "round at the sky and square at the earth" based on their imagination. There is a saying that "the sky is round like a canopy, and the square is like a chessboard." The success of Magellan's fleet's circumnavigation of the world in the early 16th century proved that the earth is a sphere.

The Earth is also called the Blue Star and the Third Planet. About 29.2% of the Earth's surface is land consisting of continents and islands, and the remaining 70.8% is covered by water.

The history of the Earth is very long. The proto-Earth was formed approximately 6.5±0.04 billion years ago. The surface of the new Earth was an "ocean" composed of magma.

The shape of the Earth is roughly ellipsoidal, with a slight bulge near the equator. The Earth is the only celestial body known to nurture and support life.

How the Sun and Earth rotate

The Earth and the Sun have always been rotating from west to east. The only difference is that the Earth revolves around the Sun, which takes about one year, while the Sun needs to lead the entire solar system to revolve around the center of the Milky Way, which takes about 250 million years to complete one revolution.

The Earth rotates from west to east all the time. From the North Pole, it rotates counterclockwise, and from the South Pole, it rotates clockwise. It takes 23 hours and 56 minutes for the Earth to rotate once. In addition to rotating, the Earth also revolves around the sun, also from west to east. It takes one year for the Earth to revolve around the sun.

The sun also rotates and revolves. The sun also rotates from west to east, but because the sun is a gaseous sphere, the rotation speed is different at different latitudes. Generally, the rotation speed is fastest in the equatorial region, and it takes 25 days to complete one revolution. The sun also leads the entire solar system to revolve around the center of the Milky Way, and one revolution takes about 250 million years.

In addition to the sun and the earth's rotation and revolution, the Milky Way also revolves around the center of the universe. All galaxies in the entire universe are constantly moving and changing. There are no completely static celestial bodies in the universe. Everything revolves and moves around each other.

Is the Earth an inner planet or an outer planet?

The Earth is an inner planet. The classification of inner planets and outer planets depends on whether the planet is inside or outside the asteroid belt. Among them, terrestrial planets such as Mercury, Venus, Earth, and Mars are all inner planets; planets such as Jupiter, Saturn, Uranus, and Neptune are all outer planets.

The eight planets in the solar system all orbit the sun, and the inner and outer planets are divided by the asteroid belt. The terrestrial planets that move within the asteroid belt, including Mercury, Venus, Earth, and Mars, are all inner planets; and the gas planets that move outside the asteroid belt include Jupiter, Saturn, Uranus, and Neptune.

The asteroid belt is a dense area in the solar system between the orbits of Mars and Jupiter. 98.5% of asteroids were discovered and named in the asteroid belt. In the space about 2.17 to 3.64 astronomical units from the sun, there is an area with the highest concentration of asteroids, called the main belt, which gathers more than 500,000 asteroids.

Regarding the origin of the asteroid belt, many mainstream scientists believe that in the early stages of the formation of the solar system, due to some reasons, many asteroids gathered between Jupiter and Mars, but they were not enough to develop into a star, so an asteroid belt was formed here.