Re: Justice For Pluto

On 31 Aug 2006 10:51:06 -0700, "mensanator@xxxxxxxxxxx"
<mensanator@xxxxxxx> wrote:


Michael Stemper wrote:
In article <1156578133.091605.188390@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>, mensanator writes:
Proginoskes wrote:
In article <1156563817.606603.198780@xxxxxxxxxxxxxxxxxxxxxxxxxxx>, JusticeForPluto@xxxxxxx wrote:

Planetary status has been stripped from Pluto.

To make this thread vaguely relevant to math, I propose that the
definition of a planet is a fuzzy one. Objects can be planets to some
extent, but there's no sharp dividing line.

The idea of being spherical due to gravity is a pretty good
dividing line. The other criteria are somewhat arbitrary.

Pluto was not discovered as a planet because of its size or shape.

"Spherical" would, of course, exclude the Earth, which is an oblate
spheroid

If I recall correctly, it was Isaac Asimov who said the Earth/Moon
system should be called a double planet because the Earth is
"pair" shaped.

with a lot of bumps on it. If we want to include the Earth,
or any other planet-like thing that's ever been observed, then we
need to say "within x% of being spherical." Where to set "x" is, by
its nature, an arbitrary decision.

--
Michael F. Stemper
#include <Standard_Disclaimer>
No animals were harmed in the composition of this message.

~v~~
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