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Are you ready for the ultimate million dollar question, little kitty?

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Now, tell me, which is the smallest planet in our solar system?

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Pluto!

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Well, I'm sorry kitty, but Pluto is the wrong answer.

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Why?

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Well, that's undoubtedly a million dollar question.

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Hey friends, a lot of us grew up reading about the old nine planets.

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But later, Pluto was delisted from its status, generating mass confusion about its identity.

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So, in today's episode, let us explore the reason behind Pluto.

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So, in today's episode, let us explore the reason behind Pluto's planetary fate.

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And answer a fascinating question.

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Why is Pluto not a planet anymore?

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Zoom in!

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Until the year 2005, every school science book thought us that there are nine planets.

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Namely, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and of course, Pluto.

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Which was the smallest amongst all?

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This celestial body was discovered in 1930 by an American astronomer, Clyde Tombaugh.

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And since then, everything was a smooth sail for students across the world.

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But on a warm day in August 2006, few scientists gathered at the International Astronomical Union in Paris.

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And astounded the world by declaring Pluto as not a planet.

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After hearing this startling news, the educational unions took notes and changed the matter in the textbooks.

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But the vital question is, why did the scientist community take its title of a planet away?

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Well, according to IAU, for a celestial body to be a planet, it needs to fulfill three essential criteria.

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First, the object should revolve around the Sun.

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Second, the object should be spherical in shape.

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And thirdly, the area around its orbit should be clear and should not have any equivalent or a bigger celestial body.

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Meaning, with the help of its gravity, the planet should clear asteroids and dwarf planets out of its way.

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I know what you are thinking, isn't Pluto spherical and revolves around the Sun?

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Yes, Pluto does fulfill these two conditions.

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But in the late 90s, space scientists found out that it doesn't meet the third criteria as it hasn't cleared the neighborhood objects around its orbit.

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Because of which it can't be called a planet and was downgraded the status of Pluto to that of a dwarf planet.

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But Pluto isn't the only one to be called a dwarf planet.

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Yes, in the Kuiper belt near Pluto, scientists found two planets, namely Homia and Makemake, which were just like Pluto.

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Not only that, but in 2005, the explorers also discovered Eris, which looked bigger than Pluto itself.

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All these newly found space objects acted like Pluto, but were nowhere similar to other planets in the solar system.

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So that's when the IAU came up with a checklist to help them classify a planet.

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And according to it, Pluto and these other planets fit into the first two criteria.

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That is, it revolved around the Sun and was spherical.

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But they didn't meet the third, which stated that the area surrounding it should be clear.

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Hence Pluto was out of Team Planet and landed on Team Dwarf Planet.

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Did you know Venetia Burney, just 11 years old at the time, suggested the name Pluto in 1930?

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Also, Pluto is the only planet in the solar system with ice volcanoes and an ocean hidden under its icy surface.

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Hope you learned something new in today's episode.

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Until next time, it's me, Dr. Binox, Zooming out.

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Aw, never mind.