pl060.html

However, every definition that I know suffers from similar problems.

And every size in between - the KB's SFD is smooth at these sizes.

	....	....	.......	.......	....	...	....	...	....	...	.... + many others
.. Eris	........	.... Pluto	............	Makemake	..........	Haumea	.......	Sedna	......	Orcus	....

Where ever we draw the line between planet and non-planet, there will be 2 almost identical objects such that one is a planet and the other is not.
(if we ever learn enough to determine if they are planets)

[BTW: I prefer a definition where if an object is part of a smooth size-distribution it is not a planet.

Does not suffer from the problem that planethood depends on distance from Sun.
Does not require that we know the mass - it is easiest to determine if it is true.
This gives 8 planets.]

(R=1200km)