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Old April 21st 04, 10:55 PM
Matthew Funke
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Default If gravity is required, what are the planets in the Solar System?

"Rodney Kelp" wrote in message
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I thought it had to do with orbit. If it orbits a sun, it's a

planet. If it
orbits a planet it's a moon. Large elliptical orbits by tiny

objects don't
count as planets. Comets and asteroids can't have moons because of
insufficient mass, therefore can't be planets.


What about 243 Ida's moon, Dactyl?
http://www.solarviews.com/eng/ida.htm

Is 243 Ida therefore a planet?

Another line of reasoning might be that what we call it is what it

is.

Sure. The bodies in question don't care.

You could have a planet floating around in deep space that has

escaped it's
sun or the sun burnt out. A lost planet? A rogue moon?


Or an asteroid or a comet?

-- Best regards,
Matt Funke