Pluto is very scary because of what will be kicked out of the nine planets?

This one wasn't kicked out because it was scary, but because it was so small, and if it was a planet, then there were many small stars in the solar system.

Because Pluto is very small, and Pluto's orbit is too unique to meet the rules of the planet, it was kicked out.

The Sun is the center of the solar system. Its mass accounts for the total mass of the solar system. Today, we describe the solar system as having eight planets orbiting around it.

In the long-standing perception of mankind, there are nine planets in the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. But in 2006, Pluto was kicked out of the ranks of planets, and the solar system became eight planets.

Pluto's past.

Pluto was controversial from the very beginning when it was chosen as a planet, with some arguing that it did not meet the criteria of a planet and was almost detached from the gravitational pull of the Sun. Others, however, disagree, believe that the planet will be surrounded by many asteroids, and that Pluto has exactly four moons around it, so it can be considered a planet.

Pluto's now.

This was completely overturned in 2006, and scientists no longer included Pluto in the list of nine planets for three reasons:

1.The planets first revolve around the sun; Able to become nearly spherical under the action of its own gravity; It is capable of clearing other celestial bodies in its orbit except for satellites. Pluto does not meet the third condition and therefore cannot be counted as a planet.

2.Small size. Pluto is only 2,360 kilometers in diameter, two-thirds the size of the Moon; Pluto was once Neptune's"Satellites"：

In 1965, researchers discovered an orbital resonance – an optimal gravitational point in the orbits between Pluto and Neptune – that prevented the two planets from getting too close to each other; Pluto's surface is covered with frozen nitrogen and methane, but it is twice as dense as icy water, so Pluto is actually a rocky planet with an ice crust.

3.Pluto's orbital parameters are different from those of the other eight planets, with an inclination of 17 to the ecliptic.

In summary, Pluto is not strictly considered a star, it is just a large rocky star. However, there are still many mysteries of Pluto waiting to be solved, and the ecological environment within it is also an unknown that we have been exploring.

Summary. The first reason: Pluto is simply too small.

The diameter of Pluto is 2,300 kilometers, which is not as good as the diameter of the Earth's satellite Moon, which has a diameter of 3,400 kilometers, which is more than 1,000 kilometers larger than Pluto. The second reason: Pluto's orbit is not in the ecliptic plane.

The eight planets are all located in the ecliptic plane, that is, the orbits of the eight planets are parallel to the ecliptic at an angle of zero, but Pluto is different, its orbit is not in the ecliptic plane, and forms a 17° inclination angle with the ecliptic plane, because its orbit is different from the orbit of the other eight planets, so it is kicked out of the ranks of the planets. The third reason: there are other celestial bodies near Pluto.

Although Pluto revolves around the Sun and forms a sphere, it is located in the Kuiper Asteroid Belt and contains a large number of celestial bodies nearby, so it cannot be counted as a planet, but can only be classified as a dwarf galaxy. The fourth reason: emotional reasons.

Pluto was kicked out of the ranks of the planets, somewhat mixed with some emotions of scientists, if Pluto is regarded as a planet, then it is unfair to the eight planets, because its orbit is different from the orbit of the eight planets; It's also not fair to Eris.

Hello, I am the teacher Yaya, the main Q&A. As far as I know, there are 4 reasons why Pluto was kicked out of the nine planets.

The first reason: Pluto is simply too small. Pluto's diameter is 2,300 kilometers, which is not as good as the diameter of the Earth's moon satellite, the diameter of the moon is 3,400 kilometers, which is more than 1,000 miles larger than Pluto.

The second reason: Pluto's orbit is not in the ecliptic plane. The eight planets are all located in the ecliptic plane, that is, the orbits of the eight planets are parallel to the ecliptic at an angle of zero, but Pluto is not on the side, its orbit is not in the ecliptic plane, and it forms a 17° inclination angle with the ecliptic plane, because its orbit is different from the orbit of the other eight planets, so it was kicked out of the planetary ranks.

The third reason: there are other celestial bodies near Pluto. Although Pluto revolves around the Sun and forms a sphere, it is located in the Kuiper Asteroid Belt and contains a large number of celestial bodies nearby, so it cannot be counted as a planet, but can only be classified as a dwarf galaxy.

The fourth reason: emotional reasons. Pluto was kicked out of the ranks of the planets, somewhat mixed with some emotions of scientists, if Pluto is regarded as a planet, then it is unfair to the eight planets, because its orbit is different from the orbit of the eight planets; It's also not fair to Eris.

Since the day it was discovered, Pluto has been associated with the word "controversy." In 1930, the American astronomer Tombo discovered Pluto, and at that time misestimated the mass of Pluto, thinking that Pluto was larger than the earth, so he named it a large planet. However, after nearly 30 years of further observation, it was found that its diameter was only 2,284 kilometers, which was smaller than that of the moon.

And the direct cause of Pluto's downgrade is the discovery of another planet larger than it outside Pluto - Xena. In this way, astronomers believe that there may be countless such "large planets" in the Kuiper Belt where Pluto and Xena are located. That's when the debate about Pluto heats up.

Astronomers are faced with the choice of either expelling Pluto from the ranks of the great planets; Either accept Xena as the "tenth planet". And the trouble with accepting Xena is that there may be hundreds or thousands of "big planets" behind her!

As a result, the International Astronomical Union Assembly adopted a new definition in August 2006 that states that a planet is a celestial body orbiting the Sun, whose gravitational pull is sufficient to overcome its rigid physical strength to make the celestial body spherical and capable of clearing other objects in the vicinity of its orbit.

According to the new definition, a celestial body that also has sufficient mass and is spherical in shape, but cannot clear other objects in the vicinity of its orbit is called a "dwarf planet". Dwarf planet members include Pluto and Ceres, among others.

Pluto is a dwarf planet. Other objects orbiting the Sun that do not meet the above conditions are collectively referred to as "small bodies of the solar system".

Pluto's identity crisis is one of its "weaknesses" due to its small size——— with a diameter of 2,274 kilometers, 1,202 kilometers shorter than the Moon, but this does not "blame" Pluto, but the overestimation of its diameter and mass.