Why Is Pluto No Longer A Planet?

Pluto is no longer a planet because it has been demoted to a dwarf planet.

Pluto was once considered the ninth planet in our solar system, but now it’s officially just one of many objects orbiting the sun.

Why Is Pluto No Longer A Planet

The International Astronomical Union (IAU) decided that the small icy world should be removed from its planetary status and placed into a new category called “dwarf planets.”

The IAU says this change will help scientists better understand how other bodies in the universe are formed.

We look at this in closer detail in this article and tell you the facts surrounding Pluto’s demotion to a dwarf planet and why it is not considered a planet in our Solar System anymore.

Let’s jump in.

An Overview Of Pluto

The solar system is made up of eight planets, two dwarf planets, hundreds of thousands of asteroids, comets, and meteorites.

Our Sun is located at the center of the solar system, which means all of these celestial objects revolve around it.

Each planet orbits the Sun at a different distance, but they are still close enough so that their gravity pulls on each other.

Pluto is a dwarf planet found in the Kuiper Belt, which is a donut-shaped class of icy bodies that orbit Neptune.

It is about 4 billion miles away from Earth.

In 1930, Clyde Tombaugh discovered Pluto while he was looking through photographs taken by an astronomer named Percival Lowell.

He noticed a faint object moving across the sky, and after further investigation, he realized it was actually a new planet.

Pluto is smaller than the moon and is a heart-shaped glacier which is the size of Texas and Oklahoma.

The world is known for having spinning moons, blue skies, and mountains as big and tall as the Rockies.

However, an interesting fact about Pluto is that when it snows, the snow is red!

Fun Facts About Pluto

Fun Facts About Pluto
  • Pluto has five moons: Charon, Nix, Styx, Kerberos, and Hydra.
  • Pluto is the largest member of the Kuiper belt.
  • Pluto is about 2/3rds water/ice and 1/3rd rock.
  • Pluto takes 248 days to complete one full rotation around the Sun.
  • Pluto is 3 billion miles away from the Sun.
  • The surface temperature on Pluto is -229 degrees Fahrenheit (-110 degrees Celsius).
  • Pluto has been visited by spacecraft, including New Horizons.
  • Pluto is not part of any constellation.

Why Is Pluto No Longer A Planet?

Pluto was demoted from planet status in 2006 after astronomers determined that it no longer met the criteria required to be classified as such.

This decision has caused some controversy because it means that Pluto is no longer considered part of our solar system.

Pluto’s orbit around the Sun is very elliptical, and its eccentricity (the ratio between how far out or close it travels) is greater than 0.1.

The other planets have an eccentricity of less than 0.01.

While this does not make Pluto a rogue planet, it does mean that it is more distant from the Sun than Neptune.

The reason for this is that when we talk about planets, we are talking about objects that orbit the sun.

But Pluto orbits the sun too, so it should be counted as one of those things.

However, if you were to draw a line through all the planets orbiting the sun, Pluto would be on the outside edge of the solar system.

This is one of the reasons why Pluto was demoted from being a planet. It is now considered a dwarf planet.

Dwarf planets are much smaller than planets, but they still orbit the sun.

They do not meet the requirements for being called a “planet” because they don’t orbit the sun at the same distance as any other planet.

The IAU committee, when demoting Pluto, also voted and passed a resolution on the criteria for what a planet is defined as.

The criteria stated that a planet is a celestial body that meets three different conditions.

A planet needs to orbit the sun, contain enough gravity so that it overwhelms the forces of other bodies to assume an almost round appearance, and have cleared the neighborhood of other orbits.

The last condition meant that the celestial body has to remove other larger celestial bodies in space.

For a celestial body to do so, then it should have more gravitational force than the neighboring celestial bodies.

However, Pluto, which is found in the Kuiper Belt, shares space with other celestial objects such as Eris, an object larger than Pluto.

As a result, Pluto was demoted by the committee. Being a dwarf planet is what makes Pluto special.

Although it is quite small compared to the other planets, it is the only object in the Solar System which meets the definition of this kind.

That is why people still like to refer to it as the unofficial ninth planet.

The International Astronomical Union, since the planet’s demotion, has said that there would be no more official naming conventions for celestial bodies.

Instead, they will use the names given by their discoverers.

Pluto’s demotion means that there are only eight planets left within our solar system.

These are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

What Does This Mean For Pluto?

Pluto is no longer considered a planet, which means that all the rules that apply to planets don’t apply to it anymore.

But Pluto isn’t alone. There are lots of other objects in our solar system that aren’t classified as planets either.

These include Ceres, Eris, Haumea, and Makemake. So why did the IAU decide to remove Pluto from being a planet?

Well, scientists say that it’s easier to study these smaller objects than larger ones.

They also think that it’ll help us learn more about how the rest of the solar system was created.

How Did Pluto Get Its Name?

How Did Pluto Get Its Name

Pluto got its name after the Roman god of the underworld.

It was named after him back in 1930 when Clyde Tombaugh discovered the first known object in the Kuiper Belt.

Tombaugh found what he thought was an unknown star and named it “Proteus.” He then realized it was a distant planet.

Following the naming tradition of the rest of the planets, Pluto was named for a God of ancient civilization; however, it wasn’t given this title by Tombaugh.

It was actually 11-year-old school girl, Ventia Burney, who suggested Pluto.

Her grandfather liked the idea and decided to pass it forward to the Lowell Observatory, and, well… the rest is planetary history!

How Small Is Pluto?

Pluto is really small. It’s about 1/1000th the size of Earth. That makes it roughly the same size as the moon (but not quite).

It’s also much smaller than any of the other planets.

It’s so tiny that this is the reason some people think it shouldn’t be considered a planet. But Pluto is still very important.

It’s the last major body left in our solar system that hasn’t been fully explored.

Scientists hope that someday we’ll find out more about Pluto and other objects like it.

And who knows, maybe someday we’ll discover life on another planet!

Final Thoughts

We hope after reading this article you have learned all you need to know about the fascinating dwarf planet that is Pluto and understand why it is no longer considered a planet in our solar system.

Though Pluto is small, it still makes for incredibly interesting space research, and astronomists believe scientists can better understand how other bodies in the universe are formed now that Pluto is no longer a planet.

Gordon Watts