I don't understand the subject.
First of all, the force is mutual, and the gravity of the celestial body is not his own.
Secondly, gravity is a particle force, its function is to pull objects to the center, which also determines why celestial bodies are moving, such as the moon around the earth, the earth around the sun, and the sun around the center of the Milky Way ... So can we not rotate? The answer is no, if the moon no longer revolves around the earth, then the moon will be attracted by the earth, which is the role of gravity. Therefore, if the celestial bodies in the universe are not swallowed up by other big celestial bodies, they must rotate. Otherwise, it is a disaster, such as a comet hitting the earth.
What happens if two massive celestial bodies meet? By wrestling, they will rotate around a point on the connecting line, which is close to the massive celestial body. This is a binary star system, and of course Trinary star system and so on.
So celestial bodies are pulled by their own gravity? I don't know what you mean. I am Ge Ping, a middle school physics teacher, and I love popular science knowledge. Welcome everyone to communicate with me and make progress together. You can gain a lot of knowledge by answering Wukong's questions. Thank you.
Celestial bodies are in motion, and the motion of celestial bodies mainly depends on "gravity" (centripetal force) and mutually exclusive centrifugal force. As a result of these two contradictory forces, a celestial body with small mass (relatively speaking, it is actually a celestial body with large mass) always moves around a celestial body with particularly large mass. But the action of forces is mutual, and all forces always appear in pairs. Therefore, one celestial body attracts other celestial bodies at the same time. In this sense, celestial bodies are pulled by their own gravity.
It depends on what you mean by pulling, running and jumping. None of this will happen.
The main feature of gravity is particle force, that is, any gravity is trying to pull everything to its own particles, so celestial bodies are round, and it is this property that pulls everything around them to the central particle, so everyone can't take a step forward when they are crowded together, and the distance from the center of mass is the same, and the circle is the perfect result.
This is the result of celestial bodies being pulled by their own gravity.
But this phenomenon will only be realized if the mass is large enough, because gravity is the smallest of the four known basic forces, so small that it can be ignored on small objects.
Science has discovered that there are four basic forces in this world. These four basic forces are strong force, weak force, electromagnetic force and gravity, which dominate the operation of all matter and energy we know.
Intensity is the dominant subatomic force, which mainly acts on hadrons such as protons and neutrons. The weak force acts on more microscopic particles, only on fermions such as electrons, quark stratons and neutrinos, which restricts the radioactive phenomenon.
These two forces are microscopic forces, and the action distance is very small. Strong force only works in the range of 10- 15m, that is, one millionth of a meter; The weak force only works in the range of 10- 18m, that is, it works in the range of one billionth of a meter. The former is femto-meter class and the latter is Ami class.
Beyond this range, they lose their function.
On the contrary, gravity and electromagnetic force, which are long-distance forces, are theoretically infinite.
But power is the strongest power in the world. If the force is 1, the weak force is110-13, the electromagnetic force is1137, and the gravitational force is110.
It can be seen that gravity is the weakest force, so weak that it is only one trillionth of the powerful force. Electromagnetic force is the second kind of force slightly weaker than force, only two orders of magnitude smaller than force.
Although electromagnetic force and gravity also play a role at the micro level, they play a greater role in the macro field. Almost everything we experience in our life is under the action of electromagnetic force, such as talking, walking, riding, making phone calls, watching stars, even spaceships, exploring hundreds of millions of light years and so on;
And gravity is more manifested in the operation of celestial bodies.
Einstein's general theory of relativity reveals the essence of gravity, that is, the disturbance of mass to space-time leads to the distortion of space-time, and this distortion is characterized by the attraction between two objects, which is gravity.
In fact, all objects with mass have gravity.
Just because the gravity is too weak, the gravity of small objects is almost negligible. For example, the gravity between two people, between people and everything we come into contact with, and even the gravity of a mountain are almost difficult to observe.
But gravity exists, and this gravitational value is the gravitational constant g, that is, the gravitational value of the distance between two particles 1kg and 1m: g = 6.67x10-1n m? /kg？ .
Newton discovered the law of universal gravitation more than 300 years ago, but the gravitational constant G was obtained by the smart cavendish through the torsion balance experiment more than 200 years ago.
The expression of the law of universal gravitation is: F=GMm/r? This formula shows that gravity is directly proportional to the mass of an object and inversely proportional to the square of the distance between particles.
From the gravitational constant G and gravitational formula, we can see that gravity is a very small force, and the gravitational constant is only 6.67n/ 1000 billion; But gravity is proportional to mass and inversely proportional to the square of distance.
In other words, the greater the mass of the object, the greater the gravity; The closer the distance between celestial bodies is, the greater and smaller the gravity will be, and it will decay exponentially.
The earth is big enough, so its gravity can attract you and me to the surface, but in daily life, you often ignore the existence of this gravity. Only when you jump high or want to leave the earth can you feel its gravity.
To get rid of its gravity, we need the second cosmic speed, which is11.2km per second.
What kind of mass can make a planet round? In the definition of a planet defined by the International Astronomical Union, a spherical celestial body is expressed as: "It has enough mass to overcome the rigid force by its own gravity, so it can take the shape of hydrostatic balance (close to a sphere)".
In the definition of dwarf planet, there is also this one.
After detection, Vesta has an average diameter of 525 kilometers and a mass of 2.7× 10 20kg, but its shape is still irregular potato-shaped, so it has not been included in the ranks of dwarf planets. Ceres has a diameter of 950 kilometers and a mass of 9.43× 10 20kg, which is 9.43 billion tons. It is already spherical, so it is listed as a dwarf planet.
Does this mean that a planet with a mass of about 654.38 billion tons will be pulled into a sphere by gravity?
Maybe, but whether a planet is round or not is not only influenced by gravity, but also by the formation process, such as the collision between some planets and asteroids.
Now we can sum up, what are the celestial bodies affected by their own gravity? First of all, if there were no gravity, there would be no celestial bodies. All celestial bodies are bound together by gravity, which will make them absorb all the substances in their gravitational circle, so that the celestial bodies will become bigger and bigger, and when they reach a certain mass, they will become spherical.
Secondly, from the gravity formula, we can see that the gravity between celestial bodies is determined by the mass and distance of both sides, which is directly proportional to the product of the mass of both sides and inversely proportional to the square of the distance.
This is the gravitational interaction between the sun and the earth, and so is the relationship between the earth and the moon.
At present, the operational relationship of all celestial bodies in the universe can be considered to be formed by the gravity of the celestial bodies themselves.
Thank you for reading and welcome to discuss.
If I understand correctly, I think the activity of our sun may answer your question. Our sun is the largest celestial body in the solar system, with a radius of 690,000 kilometers and a mass of1.989 *10.30 kg, which is 330,000 times that of the earth. The density of such a huge celestial body is only one-fifth of that of the earth. In addition to the different elemental composition, there is also a point that the core of the sun is undergoing intense hydrogen nuclear fusion reactions all the time, and these fusions generate huge energy and transmit it to the surface of the sun. Of course, this stable state can only last for another five billion years. As hydrogen gathers into helium, hydrogen is reduced, and the core of the sun will become helium, which means that the sun will turn off, and the helium core will begin to shrink under the action of gravity, and at the same time it will heat up, while the fusion temperature of helium needs to be higher, which will accelerate the fusion of the hydrogen cladding next to the core. As the temperature rises, the heat generated from it will increase and be transferred to the outer layer, making it expand outwards, and the sun will enter the red giant stage. The core continues to shrink. When the temperature reaches 1 100 million k, helium fusion will start to burn to produce carbon. Because the helium nucleus at this time is equivalent to a small "white dwarf" (electron degeneracy), runaway helium fusion will lead to helium flash, and the huge energy released will greatly expand the solar nucleus and release electrons degeneracy. Helium flash releases a lot of energy, which is likely to blow away all the hydrogen in the outer layer of the star, leaving only the helium core. The density of helium core region decreases due to expansion, and helium may burn normally in it in the future. The product of helium combustion is carbon. After the helium is extinguished, the star will have a helium shell in the core region of carbon. Because the residual mass is too small to reach the ignition temperature of carbon, the evolution of burning with helium has ended and it is heading for thermal death. This series of expansion and contraction processes is actually a competitive process between the nuclear fusion energy and gravity of the sun itself. Shrinkage indicates that gravity prevails. I don't know if this is what you want to ask, but the celestial body is pulled by its own gravity.
First of all, I want to express my understanding of the author's question. Does the author want to ask whether a celestial body can move by its own gravity?
If so, I may deny the author's question. First of all, the concept of gravity tells us that it must be produced between two interacting objects. If it is just an empty object and does not meet the conditions of gravity, naturally it cannot pull itself by gravity.
However, we can discuss this issue with open imagination. There is only one celestial body in the vast universe, so how will this celestial body move in the universe? As we know, the celestial bodies in the universe are attracted to each other, so there is revolution and rotation. So back to this question, if there is only one celestial body, how will it move?
Liu's novel Three-body actually shows us a picture of celestial movement. But it's a pity that the novel didn't mention our previous assumptions. Anyway, I think it is unrealistic to want a single celestial body to move by itself.
However, science has no end. Maybe our current way of thinking can't understand some theories, and it may become a reality in the future. I hope that in the future, we can see a more realistic theory of celestial motion.
Thank you. That's the end of my answer.
Listen to what those scientists have to say.
Cosmic world, infinite extension; There is a day outside, endless; Four-dimensional space, infinitely cited as; Macro and micro, material immortality; The mystery of its origin is beyond my knowledge. The specific answer, or ask astronomers.
I can't pull it alone, but all mankind may be able to pull it, especially scientific inventors, such as those who produce atomic bombs. Haha ~
cannot