Is Pluto really a planet?

Pluto has been the ninth planet in our solar system ever since it was found. But, Pluto is a small rocky planet with a very strange orbit. Sim it doesn't really fit in with the rest of the gaseous outer planets. Pluto is more like an asteroid. So, some astronomers don't think Pluto should be called a planet.

The International Astronomical Union (IAU)is a group that gets to decide questions for astronomers around the world. They have been talking about Pluto, and what it should be called. Since Pluto is very important to a lot of people, the IAU isn't going to say Pluto can't be a planet. They are talking about calling Pluto both a planet and an asteroid, but Pluto still is a planet!

Is Pluto really a planet?

Pluto has been the ninth planet in our solar system ever since it was discovered. However, as a small rocky planet with a very strange orbit, it doesn't really fit in with the rest of the gaseous outer planets. Pluto is much more similar to a group of objects called Trans-Neptunian Objects (TNOs), or asteroids. So, some astronomers don't think Pluto should be called a planet.

The International Astronomical Union (IAU) gets to decide questions for astronomers around the world. They have been talking about Pluto's status, and what it should be called. Since Pluto is very important to a lot of people, the IAU isn't going to take away Pluto's status as a planet. They are talking about calling Pluto both a planet and a TNO, but Pluto still is and will be a planet!

A recent programme on my local TV station suggests that Pluto is actually a large comet in orbit around the Sun, polished to a rather roundish shape. I wonder, is that possible at all?

Pluto has been the ninth planet in our solar system ever since it was discovered. However, as a small rocky planet with a very eccentric orbit, it clearly doesn't fit in with the rest of the gaseous outer planets. Pluto is much more similar to a group of objects called Trans-Neptunian Objects (TNOs), or asteroids. Thus, some astronomers don't consider Pluto to be a planet.

The International Astronomical Union (IAU) is the group that decides official questions for professional astronomers across the world. They have been discussing Pluto's status, and what it should be classified as. Since the importance of Pluto extends beyond just the astronomical world, and so many people have an interest in the topic, they have no intention of reducing Pluto's status as a planet. There has been discussion of dual listing Pluto as a planet and a TNO, but Pluto still is and will be a planet!

Last modified prior to September, 2000 by the Windows Team

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