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!

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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