New subject: planets - or not

2 Aug 2005

      Of course, if they do ever demote Pluto (and don't allow "Xena") we
could crank it back up to 9 with our "Moon".  If I remember correctly -
if you observed our Moon's orbit from above or below the plane of the
solar system - it would be a highly perturbed orbit - around the Sun.
I.e. you wouldn't see "loops" in its orbit. But, instead you would see
it "weaving in and out". 

So, I say to the IAU - give us our tenth planet or we'll take the Moon
hostage. <g>

Clear skies,
Dale.

-----Original Message-----
From:
utah-astronomy-bounces+dale.hooper=sdl.usu.edu@mailman.xmission.com
[mailto:utah-astronomy-bounces+dale.hooper=sdl.usu.edu@mailman.xmission.
com] On Behalf Of Joe Bauman
Sent: Tuesday, August 02, 2005 1:52 PM
To: Utah Astronomy
Subject: Re: [Utah-astronomy] planets - or not

Very good point, Kim. When I was talking with my son, Sky, the other 
day he suggested the same definition for a planet, large enough that 
its gravity forms it into a sphere and in orbit around a star. The 
last part rules out moons that are big enough but are not planets. I 
think it's a fine definition. The question is, what is the lower 
limit for enough mass to create a sphere? And how perfect does the 
sphere have to be? (In a sense, Jupiter isn't a very good sphere -- 
it's oblate because it is so large and spins so fast and is so 
gaseous that it bulges at the belt).) -- Joe

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RE: [Utah-astronomy] planets - or not

Dale Hooper

Kim Hyatt

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