Reason:
Various theories about the rotation of the earth are still hypotheses. Considering the cause of the earth's rotation should be combined with the earth's revolution.
There is no absolutely stationary object in the universe. Massive celestial bodies that are subjected to various external forces must rely on rotation to maintain balance in order to maintain the balance of their own motion. Particles with low mass must also rely on rotation to maintain the balance of their own motion because they move extremely fast. This point can be referred to the motion principle of a gyroscope. A rotating object has a higher tolerance to external forces during motion. The traditional view is that the sun and planets were formed from a huge primitive rotating nebula material. When these original rotating nebula materials shrink by themselves under the action of their own gravity, due to the conservation of angular momentum, the more the nebula materials shrink and become denser, the faster they rotate. When the planet is formed, the rotational angular momentum of the nebula materials becomes to seek the rotational angular momentum. First of all, the solar system originated from a mass of nebula material, which is a hypothesis in itself. Therefore, the above-mentioned traditional explanation of the origin of the earth's rotation is also uncertain. We should not regard this explanation as a golden rule. Secondly, there are many things that cannot be justified in this traditional explanation. According to this point of view, the original nebula should have rotated in the same direction and at basically the same angular speed. The planet formed in this way should have a greater mass and a faster rotation speed. All celestial bodies in the solar system should revolve and rotate in the same direction. . However, the current situation of the solar system is not like this. First, the mass of the sun is about 750 times the total mass of the planets, accounting for more than 99% of the mass of the entire solar system, but its angular momentum is only 2 of the entire system. Although the mass of the planet is small, its angular momentum is very large; secondly, the solar system is absolutely Most celestial bodies rotate counterclockwise (including revolution and rotation), but Venus and a few satellites rotate clockwise. Precisely because there are many loopholes in the traditional explanation of the earth's rotation, some scholars have proposed some new explanations. An astronomer in the United States believes that the original planet did not rotate. The sun's attraction to the primitive planet caused it to bulge, bulge, toward one side of the sun. As the original planet orbited the sun, the bulge deviated from the direction toward the sun, but the sun's attraction to the bulge pulled it back toward the sun, thus forcing the planet to spin. Of course, there are many problems with this astronomer's explanation. For example, why do most planets spin and revolve counterclockwise while lying down, while Venus spins clockwise and Uranus lies down? Modern scientific research shows that the planet's rotation is not static. The most prominent thing is that our earth's rotation has obvious fluctuations: in a year, the earth's rotation is the fastest in August, and the slowest in March and April. The rotation of the earth is not uniform in different centuries and years. For example, the earth's rotation was relatively fast in the 17th century, accelerated in the 1930s and 1940s, slowed down in the 1960s and 1970s, and accelerated again in the 1980s and 1990s. The Earth's rotation is constantly changing, which shows that there is a driving force accelerating and decelerating the Earth's rotation. So, what is this driving force? Some people say that changes in the earth's rotation are related to Antarctica. The huge glaciers in Antarctica are now slowly melting. In other words, the Antarctic continent's ice mass is decreasing and its weight is decreasing. In this way, the earth loses its balance and affects its rotation speed. However, this change is one-way, and it cannot both accelerate and decelerate the Earth's rotation. Another explanation is that the monsoon affects the earth's rotation. Some scientists have calculated that the air transferred by the monsoon from the continent to the ocean and from the ocean to the continent weighs 300 trillion tons every year. The transfer of such a large amount of material from one place on the earth to another can affect the earth's center of gravity, change the earth's angular momentum distribution, and cause the earth's rotation to accelerate or decelerate.