I did n’t eat Mercury when I was so close to the sun. Why should the celestial bodies go around?This is a balance

The solar system has 8 planets, a large number of dwarf stars, 173 planet satellites, and countless asteroids. They all run in an orderly manner around the sun.

Among all the celestial bodies of the solar system, Mercury is undoubtedly closest to the sun. It is only 58 million kilometers from the average distance from the sun. Not only that, Mercury is also the smallest of the eight major planets of the solar system. 3476 kilometers are not much bigger. It is such a small planet that is very close to the sun, but it has not fallen into the sun due to the strong gravity of the sun. Why do all the celestial bodies in the solar system play around the sun around the circle?

This is a very interesting question. Before answering this question, we must first clarify whether a celestial body will be eaten by the sun, and it has nothing to do with its size and distance.

In fact, what has been closest to the sun is not Mercury, but the "Parker Sun Detector" launched by humans on August 12, 2018. In April 2021, the Parker Sun Detector successfully crossed the Alvin interface and entered into the interface and entered into In the solar atmosphere. The nearest distance between the Parker Sun detector and the sun is only 6.9 million kilometers, which is much closer than Mercury, and its volume and quality can be ignored. Isn't it that the sun is eaten by the sun? The sun is too large, it occupies 99.86%of the total amount of material material in the solar system, so whether it is the Parker sun detector, Mercury, or even the earth, it is just a piece of dust that can be ignored for the sun. There is no difference.

So is it related to the sun? speed.

任何拥有质量的物体都具有引力，且质量越大，引力就越强，太阳作为一颗巨大的恒星，引力自然也是十分强大的，所以要想不被太阳吃掉，就要有一股力量来与Gravity confrontation of the sun. The sun is a sphere. When an object moves horizontally on the surface of the sun, a centrifugal force will be generated. The direction of this centrifugal force is exactly the opposite direction of the gravity in the center of the sun. You can fly further on the surface of the sun. When the speed of the object reaches a certain degree, the size of the centrifugal force will be equal to the gravity of the sun. At this time, the object can run around the sun without falling.

If this high -speed movement object is outside the solar atmosphere, because there is no air resistance, the speed will not decrease, so it can theoretically run around the sun eternally.

Mercury is such a high -speed moving object. The average speed of the sun is 47.4 kilometers per second. The fastest speed at the time of the recent point can even reach 192 kilometers per second. The centrifugal force produced obviously exceeds the gravity of the sun. Here we need to mention that this explanation method is only to prevent the problem from becoming more complicated and easy to understand. In fact, there is no concept of centrifugal power in physics. The so -called centrifugal force should be expressed as "lack of heart power." A new problem now is an escape problem. When the movement speed of the object is fast enough, it can get rid of the restraint of a gravitational field, and the escape speed of the solar system is 16.7 kilometers per second. Mercury has already exceeded it. Why didn't you escape?

The rate of escape from the solar system, which is what we usually call the "third universe speed", is 16.7 kilometers per second. This number has prerequisites.

The so -called third universe speed refers to the initial speed that the spacecraft should have from the earth, which means that if we want to occur from a spacecraft from the earth, it has the initial speed of 16.7 kilometers per second. You can get rid of the gravity bondage of the solar system and rush out of the solar system in one fell swoop, but the size of the gravity and the square is inversely proportional, so the closer to the sun, the greater the required escape speed. Therefore Not 16.7 kilometers per second.

When the centrifugal force and gravity of an object movement are balanced, it can never fall, and when his speed exceeds the rate of escape, it will completely get rid of the restraint of the gravitational field. What will happen to the speed of gravity confrontation, but failure to reach the speed of escape?

When the movement speed of an object is exactly balanced with the gravity, then its orbit should theoretically be a standard circle. As the speed increases, its orbit will tend to ellipse, and the faster the movement of this object, the faster the speed of this object. The more oval orbit is oval. Taking the celestial body as an example, the greater the gap between them and the long distance. Mercury is such a celestial body. Its recent point is 0.3075 astronomical units, while the long -distance point is 0.4667 astronomical units.

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