Why do the planets in the universe rotate at different speeds?

The universe we live in is composed of observable stars, planets, satellites, comets, asteroids, nebulae matter, and non-observable dark matter and dark energy. So, in terms of motion, why do macroscopic stars and planets have different rotation laws? <>

Because the gravitational force and the conservation of angular momentum of the constituent matter are important factors to promote rotation, through the balance of gravity and centrifugal force, the celestial body can have a high ability to resist external interference, so as to ensure the stability of the operation law of the star. In addition, the density of matter in the universe is extremely thin, and there is almost no external resistance to the rotation of the stars, so it can maintain a stable rotation state on a long scale. However, in the process of formation, development and evolution, stars, especially planets, are affected by gravitational interference, celestial impacts, and inner core movements, which cause corresponding changes in rotation patterns, thus showing great differences in speed, direction, and shape.

However, the rotation of the planets inherits the angular momentum of the accretion disk, and there are also factors such as the collision of the formation process and the change of the planet's inner core, so the rotation speed and rotation axis of each planet are not exactly the same as the angle between the ecliptic. Uranus is lying in circles almost on its axis facing the Sun; It takes 243 days for Venus to rotate one week (Earth day, the same hereafter), and it takes days to rotate one week, which means that it takes less time for Venus to orbit once than to rotate once, so Venus is longer than a year. <

In general, the reason for the different rotation speeds of planets in the universe is controlled by gravity and the conservation of angular momentum of the constituent matter.

The rotation of the planets in the universe depends on the gravitational pull between the planets, and because the mass and density of each planet are different, the rotation speed will also be different.

The different speeds of autobiographies on planets in the universe have many effects: 1 because of the different speeds in the movement of galaxies, 2 because of the different masses of stars.

Because each planet is located in a different position, it is also different in size, and the mass of the celestial bodies around it is also different.

Due to the influence of the sun's gravity, the surrounding material will be attracted by the sun, so there needs to be a force opposite to the centripetal force, when the object moves in a circular motion (including elliptical motion) can produce centrifugal force, the greater the speed of the object, the greater the centrifugal force. The centrifugal force must be just right, too great, and the object will not be affected by the sun's gravitational pull and move away from the sun; Too small, and the gravitational gravitational object will hit the sun. That's why the water line is the planet with the fastest orbital period in the solar system, because it is closest to the Sun and has the most gravitational pull, the more momentum it needs!

As for why it moves from west to east, it was determined when the solar system was first formed. There are many reasons for slow rotation, such as the gravitational pull of satellites, tidal phenomena, or the gravitational pull of other large planets, or the impact of cosmic objects.

When the universe was born, there was a force that made the planets rotate, and the universe has no air in a vacuum, so there is no resistance, so it keeps spinning. This is a layman's method of explanation and is relatively easy to understand.

Almost all celestial bodies in the solar system, including asteroids, rotate according to the law of the right-hand rule, and the rotation of all or most celestial bodies is also the right-hand rule. Why? The predecessor of the solar system was a dense cloud, driven by a certain force that attracted each other, and this accretion process made the density gradually larger, which accelerated the accretion process.

On the one hand, the centripetal accretion accumulation becomes the sun, and on the other hand, the gas gradually develops into a flattened shape, and in the process of development, the potential energy becomes kinetic energy, and finally the whole thing turns. At the beginning of the rotation, there are those who turn this way, and those who turn that way, after a certain direction prevails, they all become one direction, and this direction is the right-hand rule that is now discovered, and there may be other solar systems that are left-handed rules, but in our solar system it is the right-hand rule. The energy of the earth's rotation** is caused by the eventual transformation of material potential energy into kinetic energy, which ultimately means that the earth rotates on the one hand and rotates on the other.

No.

First, the cosmic velocity is also called orbital velocity. For the Earth, the first cosmic velocity is the velocity that the spacecraft must have to move around the Earth and not fall back to the Earth, and its value is kilometers and seconds. That is, when applying the first cosmic velocity, the object must have left the surface of the Earth.

The motion of objects on the surface of the Earth cannot use the concept of "cosmic velocity".

The linear velocity of rotation at the Earth's equator is 466 meters and seconds, which is much less than the Earth's first cosmic velocity.

Each planet has its own orbital velocity (first cosmic velocity). For example, the moon has a small mass, and its orbital speed is only a kilometer second; Mars orbits at a speed of kilometers and seconds; Saturn is both larger and heavier than Earth, and its orbit reaches kilometers of seconds.

Sitting on the ground and traveling 80,000 miles a day, the average is less than 1 mile per second, that is, less than half a kilometer, far less than the first cosmic speed of 7.9 kilometers per second. Even if the geostationary satellite orbit is used as the reference frame for the Earth's rotation speed, the Earth's rotation speed is still less than the first cosmic speed.

Now theoretical studies have proven that every celestial body rotates. However, the initial motivation and cause of rotation are still doctrinal assumptions, the main ones being theories such as the great universe. And the reason why many celestial bodies are shaped is near-circular or elliptical.

It is due to the centrifugal force and centripetal force caused by rotation, and this problem is based on the study of rigid mechanics. You can also use the mechanics formulas of junior high school to derive them simply. And if you want to dig deeper into this question, you can consult this ** Theory of the Shape and Rotation of Celestial Bodies——— Yizhaohua Newtonian Theory shows that Kepler's description of planetary motion is only approximate.

If a planet were attracted to only one star, its orbit would be a perfect ellipse, but in fact each planet is disturbed by the gravitational pull of the other planets, and the resulting orbital deviation is small but can be calculated and observed.