Why is Pluto no longer considered a planet? – Teach me science

Although several years have passed since Pluto was no longer considered a planet as such, a “trace” of sadness remains in our hearts. But why is Pluto no longer part of the planets in our solar system?

In 1930, Pluto was discovered by American astronomer Clyde William Tombaugh at the Lowell Observatory in Arizona.

According to NASA, Pluto is dwarf planet which is located in the Kuiper Belt >> this belt is full of icy objects like other Pluto class planets (dwarfs), however Pluto is the largest in the belt, so it is also called the ‘King of the Kuiper Belt’.

NASA itself on the Space Place portal makes a rather interesting comparison so that you can get an idea of ​​the size of Pluto. NASA compared the size of Pluto to the size of the country of the United States, the same image we’ll leave you with later.

But why are we talking about the size of Pluto? Well, this is one of the factors why Pluto has been questioned as a planet in itself, but this characteristic does not carry as much weight as others that need to be considered for a celestial body to be considered an Earth-like planet. .

The sad story of a planet that is NOT a planet

For many years, it was believed that Pluto was a planet like any other in our solar system, but it was the farthest from the Sun, and also the smallest of all its “brothers” (Mercury, Venus, Earth, Mars, Jupiter , Saturn, Uranus and Neptune).

Many years later, in 2006, around August to be exact, Pluto was questioned by the International Astronomical Union (IAU). Where it was unanimously decided to reclassify Pluto.

On August 24, Pluto fell out of the “planet” classification and became a “dwarf planet”, a situation that today is proving quite controversial for those who are not so deeply versed in the subject of astronomy.

But why did Pluto stop being considered a planet like the rest of the solar system and instead become a planet? dwarf planet? The answer is that it does not meet one of the three basic characteristics that a celestial body must meet to be considered a planet.

Pluto has the characteristic of being spherical, so it had no problem with this first characteristic. The planet also had an orbit around the Sun, so it could also be considered a planet in its own right.

So? What was the reason for excluding the planet farthest from the Sun from the family? Unfortunately, Pluto does not dominate its orbit over other massive objects, so its orbit was not “clean.”

As we mentioned at the beginning, Pluto is part of the Kuiper belt, where thousands of icy objects similar to Pluto have been discovered.