First a little introduction on our Planets. Here they are,in relation to their distance from the Sun. Closest is first.
1) Mercury
2) Venus
3) Earth
4) Mars
5) Jupiter
6) Saturn
7) Uranus
Neptune9) Pluto
All of these are the Planets. Huge sphere-like worlds that revolve around the Sun. But thats not all thats in the Solar system. We also have comets (bodies of dirt and ice that evaporate when they get near the sun, forming tails) and asteroids (pieces of rock, left over from the creation of the universe). Lately there has been a debate going on, on whether or not Pluto should be included as a Planet given its relatively small size and the little known facts about it. So last week the International Astronomical Union (IAU) sat down and laid a few rules, as to what makes a planet, a planet! Those were:
- a planet is a celestial body that revolves around a star (Sun) without itself being a star
- a planet is a celestial body with enough mass to allow gravitational forces to form it into a round, sphere-like object.
Hmm..that should have set it straight, yes? well not really. Given the new rules, several other solar system bodies qualified to be considered as planets! those were:
-What was formerly known as asteroid, "Ceres"
- Pluto's satellite, Charon
- recently discovered "2003UB313" also known as Xena!
So that put's us up to 12 planets in total! Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto and Charon as a double system, and 2003UB313-Xena. All seems good yes..? ...well not really yet!
Here are the 12 bodies, in relation to the Sun.
The boys at IAU couldnt agree on Pluto! Was it big enough to compete with the other planets, was it near enough to be consider a member of the solar system..questions questions!
So they issued another set of rules and finally decided on who's a planet and who is not..here goes:
-Planets: The eight worlds from Mercury to Neptune.
-Dwarf Planets: Pluto and any other round object that "has not cleared the neighborhood around its orbit from asteroids, and is not a satellite."
-Small Solar System Bodies: All other objects orbiting the Sun.
They have also had their eyes on a few other bodies, that need further study, in order to see if they will be named "Planets", "Dwarf planets" or something else. Here they are in relation to the Earth.
So that's just about what the status is now, in our solar system. Unfortunately though out of the 10,000 + astronomers in the world, only 424 voted for this new satus and its bound to be overturned again, as the astronomers that didnt get to vote are preparing a petition to go against this "obsurd", "rediculus" "farce" as they call it, IAU's decision.
Stay tuned!
