Why is a dwarf planet NOT a planet?

Pluto and objects like it will be known as "dwarf planets," which
raised some thorny questions about semantics: If a raincoat is still a
coat, and a cell phone is still a phone, why isn't a dwarf planet still
a planet?

Dan wrote:
Pluto and objects like it will be known as "dwarf planets," which
raised some thorny questions about semantics: If a raincoat is still a
coat, and a cell phone is still a phone, why isn't a dwarf planet still
a planet?

According to the International Astronomical Union (IAU), is a dwarf
star classified as a star?

wrote:

Dan wrote:
Pluto and objects like it will be known as "dwarf planets," which
raised some thorny questions about semantics: If a raincoat is still a
coat, and a cell phone is still a phone, why isn't a dwarf planet still
a planet?

According to the International Astronomical Union (IAU), is a dwarf
star classified as a star?

Pluto knows he is a planet and that's all that really counts. :-)
James E. Klein


Engineering Calculations
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the KDP-2 Optical Design Program
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Dan wrote:
Pluto and objects like it will be known as "dwarf planets," which
raised some thorny questions about semantics: If a raincoat is still a
coat, and a cell phone is still a phone, why isn't a dwarf planet still
a planet?

Well, a guinea pig isn't a pig.

In math there are things called "rings", that have addition,
subtraction, and multiplication. There are also "non-associative
rings" that are like rings but don't satisfy the associative property;
and they are not considered to be rings.

There are also "multivalued functions", in which one input can yield
multiple outputs. They are not functions.

To be sure, this kind of terminology does strike many mathematicians as
odd, at least upon first exposure. But they are quite well established.

On 24 Aug 2006 17:22:59 -0700, wrote:


Dan wrote:
Pluto and objects like it will be known as "dwarf planets," which
raised some thorny questions about semantics: If a raincoat is still a
coat, and a cell phone is still a phone, why isn't a dwarf planet still
a planet?

I assume that Dwarfs Planets are not *currently classified* as planets
so that some day, IF it is necessary, "Dwarf Planets" can be called
"Planetoids" (or whatever word you want) and be declared as separate
from the class of the Classic 8 Planets. Just a thought.

-- Kevin Heider

West Coast Swing Photos at:
http://www.pbase.com/kheider

Dan wrote:
Pluto and objects like it will be known as "dwarf planets," which
raised some thorny questions about semantics: If a raincoat is still a
coat, and a cell phone is still a phone, why isn't a dwarf planet still
a planet?

Same reason an extra-solar planet isn't a planet: the IAU is confused
about language.