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!


Submitted by Matt (Missouri, USA), Kristin (Texas, USA), Karen (Hong Kong), Matthew (New York, USA), Ian and Christi (Oregon, USA)
(May 4, 1999)


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