Obvious (Score 1)

The definition of a planet should include how it orbits it's star. The Main 8 Planets all orbit in the same direction in the same plane to the sun, therefore they were created in the accretion disk of our sun at the birth of our solar system. Other bodies that orbit the sun but are not in the same plane should not be called planets because they were not massive enough to with stand the start of fusion shockwave that blew away alot of the small debris in the early solar system. Because a stellar body is sphereical does not mean it is a planet, the most common shape for objects in the universe is sphereical.