At 07:08 PM Monday 8/28/2006, Deborah Harrell wrote:
Somebody noted that Pluto is now a dwarf planet-
PAT MATHEWS [EMAIL PROTECTED] wrote:
Likewise, in my house I have two mutant dwarf
mountain lions. G
I, OTOH, have an American SportCat who *thinks* he is
a mutant cougar (why else would he stalk and chase
deer?!), and one shameless flirt of a Mountain Kitten
(TM) (as opposed to a Coyote Pup...or something). ;)
serious
Earth-Moon was mentioned as being a double planet; is
this the accepted term, or is it still debated? I
think it makes sense, since IIRC somone calculated
that Earth's orbit would be at a different place if
there was no Moon...
The mass of the Earth is 81.3 times the mass of the Moon. The
barycenter (center of mass, or where they would balance if you put
the Earth and Moon on opposite ends of a giant see-saw) of the
Earth-Moon system is about 3000 miles from the center of the Earth,
or about 1000 miles below the surface of the Earth. No other planet
(2006 official definition :) ) in the solar system has a satellite
which is so large compared to the planet itself (e.g., four of
Jupiter's satellites are about as large as or larger than our Moon,
but Jupiter itself is 318 times the mass of Earth, so they are much
smaller compared to the planet they orbit than the Moon is compared to Earth).
Also, in structure and composition, the Moon is similar to the four
terrestrial planets and so is frequently considered with them from a
planetary science point of view. That does not make it a planet
according to the official definition, however.
-- Ronn! :)
___
http://www.mccmedia.com/mailman/listinfo/brin-l
