The movement of the earth around the sun is called revolution. Seen from above the North Pole, it rotates counterclockwise around the sun. The route of the earth's revolution is called orbit. It is an elliptical orbit close to a perfect circle. The sun is located in one of the two focal points of the ellipse. Every year, 6543810.3, the earth moves to the nearest position to the sun, which is called perihelion.

On July 4, the earth moved to the farthest position from the sun, which is called apohelion. The direction of the revolution of the earth is also from west to east. The length of the orbit is 940 million kilometers, and the time required for one revolution is one year, about 365.25 days. The average angular velocity of the earth's revolution is about 1 degree per day, and the average linear velocity is about 30 kilometers per second.

The perihelion has a faster revolution speed, while the apohelion has a slower revolution speed. The plane on which the earth rotates is called the equatorial plane, and the plane on which the earth revolves is called the ecliptic plane. The angle of intersection between the two planes is called the ecliptic angle, and the earth axis is perpendicular to the equatorial plane, and the angle of intersection with the ecliptic plane is 66 34', or the angle of intersection between the equatorial plane and the ecliptic plane is 23 26', indicating that the earth revolves around the sun obliquely.

Introduction to the earth:

The earth belongs to the solar system in the Milky Way, between Venus and Mars. It is the third closest planet to the sun in the solar system and has a natural satellite. The earth was the first planet to discover life.

The earth environment in which the earth is located refers to the cosmic environment centered on the earth, which can be understood from both macro and micro levels. Macroscopically, it refers to the position of the earth in the celestial system, that is, the earth-moon system-solar system-galaxy-total galaxy; Microscopically, it refers to the position of the earth in the solar system. In the infinite space, the earth is just a drop in the ocean, in an endless movement.

Many geophysicists believe that the existing weight of the earth is one million times that of 6 trillion tons. If the earth's interior is not empty, its weight should be much more than that. The existing weight of the earth is one million times that of 6 trillion tons, which is controversial. Measuring the weight of the earth can not be calculated only by several mathematical formulas, nor can we abandon the gravitational effect of the sun on the earth.