Old debate re-opened - What is a planet?
- dave_lillis
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20 years 8 months ago #2387
by dave_lillis
Dave L. on facebook , See my images in flickr
Chairman. Shannonside Astronomy Club (Limerick)
Carrying around my 20" obsession is going to kill me,
but what a way to go.
+ 12"LX200, MK67, Meade2045, 4"refractor
Replied by dave_lillis on topic Re: Old debate re-opened - What is a planet?
Ok, this is the way I see it.
Planet = body with a diameter greater then 1000km/miles which orbits a star/s, implying that it orbits nothing else.
2 exceptions
1, double/multiple planet, where both/all bodies have a diameter greater then 1000km AND their center of gravity is located outside of either mass, (they obviously orbit each other and that pair/set orbit the star).
2, rogue planet, where a body greater then 1000km is wondering in intersteller/intergalactic space with no associate star, (presuming it is not a star itself).
Shape/brightness/observability/direction or composition do not come into it.
Planet = body with a diameter greater then 1000km/miles which orbits a star/s, implying that it orbits nothing else.
2 exceptions
1, double/multiple planet, where both/all bodies have a diameter greater then 1000km AND their center of gravity is located outside of either mass, (they obviously orbit each other and that pair/set orbit the star).
2, rogue planet, where a body greater then 1000km is wondering in intersteller/intergalactic space with no associate star, (presuming it is not a star itself).
Shape/brightness/observability/direction or composition do not come into it.
Dave L. on facebook , See my images in flickr
Chairman. Shannonside Astronomy Club (Limerick)
Carrying around my 20" obsession is going to kill me,
but what a way to go.
+ 12"LX200, MK67, Meade2045, 4"refractor
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- John OBrien
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20 years 8 months ago #2389
by John OBrien
"We are the music makers ... and we are the dreamers of dreams." - W.W.
Replied by John OBrien on topic Re: Old debate re-opened - What is a planet?
Some quotes from Dr. Alan Stern leader of the new horizons mission to Pluto...
On size:
"You wouldn't deny a chihauhau a place among dogs because it is too small"
On having too many planets:
"if your brain was so completely full of names of people that it just couldn't take any more, would anyone new who you met after that, therefore not be a person?"
On size:
"You wouldn't deny a chihauhau a place among dogs because it is too small"
On having too many planets:
"if your brain was so completely full of names of people that it just couldn't take any more, would anyone new who you met after that, therefore not be a person?"
"We are the music makers ... and we are the dreamers of dreams." - W.W.
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- stepryan
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20 years 8 months ago #2391
by stepryan
Replied by stepryan on topic Re: Old debate re-opened - What is a planet?
seeing that the word planet was derived from the old greek word meaning wanderer, i contend everything in the universe that moves through the heavens is a planet .
stephen.
stephen.
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- dave_lillis
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20 years 8 months ago #2397
by dave_lillis
Would you call a girl a woman or a boy a man ???? :lol:
Dave L. on facebook , See my images in flickr
Chairman. Shannonside Astronomy Club (Limerick)
Carrying around my 20" obsession is going to kill me,
but what a way to go.
+ 12"LX200, MK67, Meade2045, 4"refractor
Replied by dave_lillis on topic Re: Old debate re-opened - What is a planet?
Some quotes from Dr. Alan Stern leader of the new horizons mission to Pluto...
On size:
"You wouldn't deny a chihauhau a place among dogs because it is too small"
On having too many planets:
"if your brain was so completely full of names of people that it just couldn't take any more, would anyone new who you met after that, therefore not be a person?"
Would you call a girl a woman or a boy a man ???? :lol:
Dave L. on facebook , See my images in flickr
Chairman. Shannonside Astronomy Club (Limerick)
Carrying around my 20" obsession is going to kill me,
but what a way to go.
+ 12"LX200, MK67, Meade2045, 4"refractor
Please Log in or Create an account to join the conversation.
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