1. Pluto was named a planet because they didn't know there were other objects out there like it.
2. Pluto was NOT named in a contest!
3. Since finding all of these other objects, astonomers haven't been able to decide on the definition of a planet, ie just because it is spherical might not necessarily make it a planet-- it has yet to be decided. Distance has nothing to do with it.
4. Take note that the asteroid Ceres was considered a planet until astronomers realized it was just part of the asteroid belt. The Kupier belt is just like a larger asteroid belt.
5. If you must have a mnemonic, you're forgetting Varuna, Quaoar, Ixion, 2004 DW and 2002 AW197, the other major Kupier Belt objects found before Sedna. Also, Pluto's moon Charon is half the size of Pluto, and about the size of the other objects I just mentioned.
Here's a list of the KBO's.
Edited by - MEGAߥTE on 4/8/2004 8:42:21 PM