Why are there only eight planets in the solar system?

There were originally nine, and one was kicked out.

The laws of nature, which cannot be explained.

Here's why:

Nine planets used to be a popular term, but since the International Astronomical Union in 2006, when it voted to downgrade Pluto as a dwarf planet, there have only been eight planets in the solar system.

In Resolution 5, adopted at the 26th session of the International Astronomical Union held in Prague on 24 August 2006, Pluto was classified as a dwarf planet and removed from the list of nine planets in the solar system. Dozens of other planets larger and heavier than Pluto did not crowd the ranks of the stars, and the solar system became eight planets, while Pluto was relegated to a dwarf planet.

Characteristics of the Eight Planets:

Jupiter-like planets, including Jupiter and Saturn, are mainly composed of liquefied gas, are much larger in volume and mass than terrestrial planets, are farther from the Sun, less dense, are located outside the asteroid belt, and have halos.

Perihelio-solar planets, including Uranus and Neptune, are between the first two in volume and mass, the furthest from the Sun, are composed mainly of solidified gases, are also densely so, have lower surface temperatures, and have halos.

Jupiter is the largest of the eight planets, enough to fit the other seven. Neptune is the farthest of the eight planets from the Sun and has a pale blue light. Venus is the second closest planet to the Sun.

Because it never rains on Venus, the entire planet is covered in dust and very arid throughout the year.

In descending order of distance from the Sun, they are: Mercury ( ), Venus ( ), Earth ( ), Mars ( ), Jupiter ( ), Saturn ( ), Uranus ( ), Neptune ( or ).

Most of the eight planets also rotate in the same direction as their orbit. There are only two exceptions: Venus and Uranus. Venus rotates in the opposite direction to its orbit, while Uranus rotates "lying" at an angle of 97° to its orbit.

Definition of planets: first, celestial bodies that must orbit stars; Second, the mass is large enough to rely on its own gravity to make the celestial body spherical; The third is that there should be no other objects in the vicinity of this orbit (clean up other objects in its orbit). According to this division, there are only eight planets in the solar system: water, metal, earth, fire, wood, and earth, plus the king of heaven and the king of the sea.

The universe is very large, consisting of planets, moons, and so on, including the Milky Way, the Solar System, and ......There are eight planets in the solar system, what do you know about these, today I will introduce them to you, if you don't know, you can take advantage of this to understand, let's take a look.

With the Sun as the center, from the inside to the outside are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. There was also a Pluto before, but now it is expelled. <>

Earth is by far the only planet that can support life, and it has the right temperature, humidity, drinking water for humans, and gravity, while other planets do not have these conditions. Mercury is the closest planet to the Sun, Neptune is the farthest planet from the Sun, Jupiter is the most massive planet, most of the Earth is ocean, from above**, it is a blue and blue, so it is also called the "Blue Planet", Mars, just listen to the name, like fire, it looks red, it is called the "Red Planet", and each Earth has its own characteristics. <>

Each planet has its own orbit, and they all follow the direction of the Sun's revolution in their orbit and never stop. Maintaining the basic operation of the solar system, human beings have realized their dream of landing on the moon, and now they have made great breakthroughs in the study of Mars, so people may immigrate to other planets in the future! <>

To sum up, this is the introduction I provide for you about the eight planets of the solar system, you can take a look if you are interested, of course, this is my personal point of view, not authoritative, everyone has a good opinion, a wise man sees wisdom, 1000 readers have 1000 Hamlets, so we have to look at these issues with our own thinking, those astronomy enthusiasts can also take a look, what other thoughts and opinions, remember to leave a message in the comment area.

The eight planets include Venus, Jupiter, Mercury, Mars, Saturn, Pluto, Uranus, and Neptune. The mass and volume of these eight planets are different, and their characteristics are also different.

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. These are the 8 planets in the solar system.

I don't know much because I'm not very interested in this aspect of knowledge.

1. Mercury, orbital period: days.

Mercury is closest to the Sun and is the smallest planet in the solar system in terms of volume and mass. Often at the same time as the sun, it was called "Chenxing" in ancient China. Mercury is smaller in diameter than Ganymede and Titan.

2. Venus, orbital cycle: days.

The sixth largest planet in the solar system, known in ancient China as Taibai or Taibaixing. It is sometimes the morning star, and dawn appears in the eastern sky and is called "enlightenment"; Sometimes it is called a twilight star, and after dusk, the western sky appears, which is called "Chang Gung".

3. Earth, orbital period (days):

Earth is the third planet from the Sun and the fifth largest planet in the solar system.

4. Mars, orbital period: days.

Mars is the fourth closest planet to the Sun and the seventh largest planet in the Solar System. In ancient China, it was called "glowing star", and the phenomenon of Mars "staying" in the heart is called glowing confusion and guarding the heart. Mars (Greek: Ares) is known as the god of war.

5. Jupiter, orbital cycle: years.

Jupiter is the fifth planet from the Sun and the most massive of the planets in the Solar System, with a mass of all seven planets combined, 318 times the size of the Earth, and 1,316 times the volume of the Earth. Known as the "King of the Planets".

6. Saturn, orbital period: days.

Saturn, the sixth-farthest planet from the Sun and the second largest of the eight planets, is known as "Zhenxing" in ancient China, and is the least dense planet in the solar system and can float on water. In Roman mythology, Saturn was the name of the god Saturn.

7. Uranus, orbital cycle: years.

Uranus is the seventh farthest planet from the Sun in the Solar System and the third largest planet in the Solar System in terms of diameter. Uranus is larger than Neptune's body, but its mass is smaller.

8. Neptune, orbital period: days.

Neptune is the eighth planet orbiting the Sun and the fourth largest body in the Solar System (in diameter). Neptune is smaller than Uranus in diameter but has a greater mass.