What rules do you believe make for a definition that isn’t contrived? How do you exclude asteroids from your definition or reject other dwarf planets like Ceres without making up contrived exceptions of your own?
Planets are round, naturally formed bodies orbiting a star. (I know no planet is perfectly round and you can call any defined tolerance “contrived”, but at that point there are no useful and universally fitting definitions for anything in nature. Definitions are always categorizations by human standards)
Many asteroids are round. The list of planets, under your definition, would be so large it isn’t useful anymore. Even when Ceres, Pluto, and Eris were called planets the list was getting too long, and there are several larger than Ceres. Including every nominally round object would be insane.
What rules do you believe make for a definition that isn’t contrived? How do you exclude asteroids from your definition or reject other dwarf planets like Ceres without making up contrived exceptions of your own?
Planets are round, naturally formed bodies orbiting a star. (I know no planet is perfectly round and you can call any defined tolerance “contrived”, but at that point there are no useful and universally fitting definitions for anything in nature. Definitions are always categorizations by human standards)
I propose a better definition:
Planets are very large objects orbitting a star that dwarf everything nearby
I’m pretty sure this is the intent of the IAU’s definition. It’s just more specific.
Ah, yes. “very large”, “dwarf everything”, and “nearby” are very specific terms…
Yes, that is why I mentioned the IAU’s definition was more specific.
Very large? Enough mass to have a round shape.
Dwarf everything nearby? Clear out its orbit by colliding with/capturing/ejecting shit.
Many asteroids are round. The list of planets, under your definition, would be so large it isn’t useful anymore. Even when Ceres, Pluto, and Eris were called planets the list was getting too long, and there are several larger than Ceres. Including every nominally round object would be insane.