The planet we live in, the earth, is our home, so this planet is awesome and admirable from the day when there are human beings. No matter what people called it at that time, human feelings for the earth never changed. But the earth is the most common planet in the universe, even in the solar system. In the solar system where the earth exists, there are nine planets, ranking fifth by volume and third by distance from the sun. The average distance from the sun is 65.438+0.5 billion km, and Mercury and Venus are inside the earth. The density of the earth is 55 15 kg per cubic meter. Like other planets in the solar system, the earth rotates around the sun at the same time. Because the earth where we live is the planet we are most familiar with, we call the other eight planets terrestrial planets. From this point of view, our home earth is an ordinary planet, but why is it that only humans live on the earth in the solar system?

In fact, there are also extraordinary places in this ordinary characteristic, and it is the particularity of the earth itself that has created a colorful world on the earth. From the position, the distance between the earth and the sun is moderate, and the temperature is suitable. From the birth of the solar system to the earth, there are traces of primitive life, and the sun has not changed significantly. Under this stable lighting condition, it is possible to breed life on the earth. On the other hand, the position between the earth and other planets is reasonable, the direction of revolution around the sun is the same, and the orbital plane is the same, which determines that the evolution of the earth is not interfered by other planets; The earth itself is a special physical and chemical system, which is different from other planets in the solar system. The volume and mass of the earth determine the evolution of geophysical and chemical forms. At the same time, the liquid hydrosphere, the atmosphere formed by nitrogen and oxygen, and the plate movement of the solid geosphere have gradually made the earth less common.

Based on these unique characteristics of the earth, water began to form a primitive ocean under the influence of the earth's geological forces and primitive atmosphere, and the origin of life began in this blue world.