The question of why Pluto was deprecated as a planet is one of those questions on everyone’s mind, whether you’re interested in astronomy or not, because for a long time it was considered a planet but one day excluded, it will no doubt confuse anyone who knew it was a planet before.
Pluto is now known as a dwarf planet . Of course, there is a reason why this planet is separated from other planets. In this article, we’ll take a detailed look at what’s happened since Pluto’s discovery and help you understand what’s going on in the background.
What is Pluto?
Pluto is a dwarf planet. Like many other planets, Pluto orbits the Sun, but what sets it apart from other planets is its relatively small size.
Also known as Pluto, the planet was discovered in 1930 by Clyde Tombaugh. During this period, it was almost as if a planet hunt was started. The search for a new planet was embarked. Tombaugh, an astronomer from the United States, was studying stars in space at the time. The planet’s name was suggested by Venetia Burney, an 11-year-old girl.
The discovery made headlines around the world. Hundreds of suggestions came from all over the world to name the newly discovered object, but Burney suggested the name Pluto and his proposal was accepted. Pluto officially became Pluto on March 24, 1930. Its name was announced on May 1, 1930.
It takes 248 years for Pluto to revolve around the Sun. Its distance from the Sun is several tens of times greater than the Earth’s distance from the Sun. The planet has a total of 5 moons. These satellites can be listed as follows:
Pluto’s largest moon is Charon. It corresponds to about half of Pluto. The planet is very cold. It has less gravity than Earth. Therefore, a human or animal would weigh less on this planet than it does on Earth.
How Was Pluto Found?
NASA sent a spacecraft in 2006 to approach Pluto. The name of this vehicle was New Horizons. It took about 10 years for the spacecraft to get this far from Earth. As New Horizons passed by Pluto and its moons towards the end of 2015, it collected some data about the planet and its surroundings.
The data and images collected by the spacecraft have helped scientists learn more about the dwarf planet.
Why Was Pluto De-Planetized?
Pluto was removed from planetary status because it did not meet one of the three criteria set by the International Astronomical Union (IAU for short) . According to the dwarf planet definition made by the IAU, three criteria must be met for a planet to be considered a complete planet.
These criteria consist of:
- The planet must orbit the Sun.
- It must have sufficient mass for hydrostatic equilibrium.
- Its orbit must be clear of other objects.
Pluto meets only two of the three criteria above. By the third, it fails to become a full planet. Despite standing there for billions of years, it has not succeeded in clearing its surroundings from other objects.
An object that does not meet all of these criteria, no matter how large, is now classified as a dwarf planet. Pluto was also classified as a dwarf planet by the IAU in August 2006. Another planet that shared the same fate as Pluto was Ceres. It was discovered in 1801 by the Italian astronomer Giuseppe Piazzi.
Will Pluto Be Considered a Planet Again?
According to the IAU, which is responsible for determining the status of all celestial bodies, Pluto is not yet considered a planet in the Solar System. It seems unlikely that Pluto will be accepted as a planet after that.
There are many who do not agree with this decision, accepting Pluto as a real planet, and objections have increased tremendously, especially in the last few years. Despite all these objections, it was not considered appropriate to re-evaluate Pluto.
Observations of Pluto, which was considered the ninth planet in the Solar System shortly after its discovery in 1930, revealed that it was smaller than assumed.
By the early 21st century, many astronomers began to discover objects larger than Pluto. These discoveries led to the discussion of that obvious question: Should the IAU classify all these objects as planets?
The IAU held a meeting in August 2006. A decision was made at this meeting. According to this decision, three conditions were determined for an object to be considered a planet. The first condition was that the object was orbiting the Sun.
Of course, most objects meet this condition. It was the second and third conditions that mattered. The second condition was that the object had a spherical shape. When an object is large and massive enough, gravity will make it a sphere. Pluto naturally satisfies this condition.
When it comes to the third condition, Pluto bids farewell to the title of the ninth planet , because according to the third condition, the surrounding of the planet must be free from other objects. From this point on, only 8 planets remain in the Solar System.
These planets are listed as follows:
We have come to the end of the article where we answered questions such as why Pluto was removed from planetary status, will it be accepted as a planet again, and briefly talked about Pluto’s history.