Will the Earth stop rotating?

No, the Earth, like the other eight planets in the solar system, orbits the sun at the same time. It rotates around an imaginary axis of rotation, which is the rotation of the Earth. Hundreds of years ago, many methods were proposed to prove the rotation of the earth, and the famous "Foucault pendulum" made us really see the rotation of the earth, but why does the earth rotate around its axis?

Why does it revolve around the sun? This is a question that has been of great interest to scientists for many years, and roughly speaking, rotation is a basic form of motion of the celestial bodies in the universe, but in order to really ask this question, it is necessary to first understand how the sphere and the solar system are formed. The creation of the Earth's rotation and revolution is closely related to the formation of the solar system.

Modern astronomical theories suggest that the solar system was formed by the so-called primordial nebula, a very thin cloud of gas that contracted to the center under the influence of some kind of perturbation 5 billion years ago. After a long period of evolution, the density of the matter in the central part became higher and higher, and finally it reached the point where it could trigger a thermonuclear reaction, and it evolved into the sun. The residual gas around the sun gradually forms a rotating disk-like gas layer, which gradually gathers into solid particles, microplanets, and primordial planets in the gas layer through the processes of contraction, collision, capture, and accumulation, and finally forms independent solar system objects such as large planets and asteroids.

We know that to measure the speed of a straight-moving object, it can be expressed in terms of velocity, so what is the measurement of the rotation of the object? One way to do this is to use "angular momentum". For an object revolving around a fixed point, its angular momentum is equal to the mass multiplied by the velocity, multiplied by the distance of the object from the fixed point.

There is a very important law of conservation of angular momentum in physics, which is to say, a rotating body. If it is not acted upon by an external moment, its angular momentum does not change due to the change in the shape of the object. For example, a ballet dancer, when he suddenly folds his arms in the middle of rotation (the distance between the center of mass and the fixed point becomes smaller), his rotation speed increases, because only in this way can the angular momentum be maintained.

This law plays an important role in the generation of the Earth's rotation speed. The primordial nebulae that formed the solar system originally had angular momentum, and after the formation of the solar and planetary systems, its angular momentum would not be lost, but it would inevitably be redistributed, and each star would get a certain amount of angular momentum from the primordial nebula in the long process of accumulating matter. Since angular momentum is conserved, the planets will also rotate faster and faster during contraction.

The earth is no exception, the angular momentum it obtains is mainly distributed in the rotation of the earth around the sun, the mutual rotation of the earth-moon system and the rotation of the earth, which is the origin of the earth's rotation, but to really analyze the orbital motion and rotation motion of the earth and other major planets still requires scientists to do a lot of research work.