Pluto - make your minds up dudes...

If you are like me, you were upset, and annoyed, when a definition for a “planet” was created, as this meant that Pluto was no longer a planet. This was very very upsetting for many many people. Well, you may be able to stop crying. Let us hope so. Because, next week, the IAU are meeting, and are going to discuss the definition of a planet. Currently, the definition of a planet is

a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.

This definition means that Pluto (as it has a number of other objects in it’s orbit) is not a planet. It is a dwarf planet, which covers (a) and (b), but not (c). The idea, by some people, is to get rid of (c) and just use the first 2 bits of the definition. This would mean that Pluto would be a planet again (woo!) but would also mean that Ceres (the largest meteor in the meteor belt between Mars and Jupiter), a number of plutioniun objects, and the moon (huh?) would become planets.

Now, you may be saying “Why can’t Pluto just be a planet, never mind the rest of them.” Well, some people are saying that we should not have a definition of a planet, that planets should evolve in the public conciousness. Which means, lets be honest, that there would be 9 planets again. Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Venus and Pluto. (A rhyme anyone?)

I am not sure which I prefer. I just want Pluto to be a planet, but the moon? Thats a bit weird.

Anyways, make your own mind up about what you think, and when I hear something, I’ll tell ya. You can read more about it here, at