Re: Naming days of the week and months of the year????

Henrik worte:
>Hi!
>
>Nik Taylor <fortytwo@...> writes:
> > Raymond Brown wrote:
> > > We now have nine planets - but a nine-day week is too long
> >
> > Some astronomers don't consider Pluto a planet (in fact, didn't the IAU
> > officially declare it not a planet?
>
>Hmm??  Who not?  It circles around the sun, ergo it's a planet.
Hm. Well, Pluto orbits the sun, yes. So does millions of asteroids, billions
of comets, thousands of Kuiper objects and any number of dust particles.
None of these are classified as planets.

A planet is a celestial body that's too small sustain hydrogen-to-helium
fusion (deuterium fusion and lithium fusion is okay). There is no fixed
lower limit - Mercury is classified as planet, while Ganymede despite being
bigger is classified as a moon (aka satellite). In practice, if an object
orbits a planet it gets classified as a moon, if it orbits a star it gets
classified as planet, asteroid, meteorid, Kuiper object or comet depending
on size and combosition.

The thing with Pluto is that it is much smaller than any (other), while much
larger than any (other) Kuiper object. It's also got a relatively hugish
moon, so some would classify it as a double planet, or a double Kuiper
object. Astronomers aren't good at strict classifiaction ...

ObConlang: My SF conlang Tairezazh doesn't have word of 'planet' at all. Gas
giants like Jupiter are considered belonging to entirely other class of
objects than rocky planets like Earth. They'd classify Pluto as a Kuiper
object.

                                                    Andreas

PS FYI, some astronomers would classify the Earth and the Moon as a double
planet.

                                                         Andreas
_________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.

Reply