Our solar system has just lost one planet...

General discussion about the two books by Michel Desmarquet. Please ONLY post questions that do not fit in any of the available specialized forums.

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dloheb
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Post: # 7372Post dloheb »

bomohwkl wrote:
Robanan wrote:From what I can think of the only thing that makes a difference between a planet and a round rock in space is the point that a planet has a core (might be cold or active) this would in turn affect the gravitational field of the object (polarize it?).
I was an avid learner of astronomy. As a matter of fact, it depends by what you mean by cores. Pluto has a core. Our moon has a core and the four largest satellites of Jupiter have cores too.
Does the idea of 9 planets revolving around their sun hold true as far as you know?
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Robanan
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Post: # 7379Post Robanan »

bomohwkl wrote:
Robanan wrote:From what I can think of the only thing that makes a difference between a planet and a round rock in space is the point that a planet has a core (might be cold or active) this would in turn affect the gravitational field of the object (polarize it?).
I was an avid learner of astronomy. As a matter of fact, it depends by what you mean by cores. Pluto has a core. Our moon has a core and the four largest satellites of Jupiter have cores too.
According to TP those are all plantes too, true that they don't form a solar system they are moons as you noted (except pluto). My definition of the core is the same as the definition of the core of our planet.
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Post: # 7512Post survivor »

Lena wrote:I wonder where the next planet will come from


Eris is making a big splash to replace Pluto.

http://www.cosmosmagazine.com/node/657

Astronomers were initially divided over how to classify Eris, which has also been known by its numerical designation, 2003 UB313. Some argued that it should be welcomed as the 10th planet in our Solar System, while others said both it and Pluto were not worthy of planethood.

“I think it’s bringing things back to way they should have been all along,” said Bryan Gaensler, an astronomer at the University of Sydney, and member of the Editorial Advisory Board of Cosmos. “It’s really a historical accident that Pluto was ever a planet in the first place.”
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Shen
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Re: Our solar system has just lost one planet...

Post: # 13133Post Shen »

It just got me more and more confused...
When Thaora said that it cannot be wrong...but now solar system has 8...what about other systems...
From the news I can tell there are 4,7....
All nine?
Oh no.
Everything you will experience is a lesson to be taught.
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Rezo
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Re: Our solar system has just lost one planet...

Post: # 13135Post Rezo »

http://en.wikipedia.org/wiki/Dwarf_planet

there are many of them. there even are bodies in space termed 'rogue planets' [outside solar systems]. a whole other story there!

im no expert on either, but it seems those saying pluto is not a planet is because it goes into neptunes orbital path and is not in the same plane of revolution around the sun [avg 17 degree difference]

but id also not consider eris a planet for the same reason. its orbit is pretty eccentric!
" There is a single general space, a single vast immensity which we may freely call void: in it are unnumerable globes like this on which we live and grow, this space we declare to be infinite, since neither reason, convenience, sense-perception nor nature assign to it a limit."

-Giordano Bruno
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Rezo
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Re: Our solar system has just lost one planet...

Post: # 13136Post Rezo »

actually, I was looking at Quaoar, a sort-of recently discovered termed 'dwarf planet' in the kuiper belt [as is pluto], but of the other said dwarf planets, though Quaoar's diameter is roughly half of Pluto, and has a mass similar to Pluto's moon, Charon. It has a moon, called Weiwot.

The orbit of Quaoar seems to have a very close similarity with the orbit pattern of the other planets [save pluto's]. conceivably it 'could' be considered a planet, except for the difficulty in estimating its curvature

http://www.space.com/25817-quaoar.html
http://www.en.wikipedia.org/wiki/50000_Quaoar

edit: more recent info suggests its shape is ellipsoid, disqualifying it as 'planet'

http://www.newscientist.com/article/dn2 ... 5CM3C8WdZE

Ceres, was thought to be an asteroid, but this past january, was shown to emit water vapor; and a probe is scheduled to arrive there next year sometime [unmanned Dawn spacecraft]. and it also has an IAU-conforming orbit..? I think

http://en.wikipedia.org/wiki/Ceres_%28dwarf_planet%29
" There is a single general space, a single vast immensity which we may freely call void: in it are unnumerable globes like this on which we live and grow, this space we declare to be infinite, since neither reason, convenience, sense-perception nor nature assign to it a limit."

-Giordano Bruno
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Rezo
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Re: Our solar system has just lost one planet...

Post: # 13137Post Rezo »

" There is a single general space, a single vast immensity which we may freely call void: in it are unnumerable globes like this on which we live and grow, this space we declare to be infinite, since neither reason, convenience, sense-perception nor nature assign to it a limit."

-Giordano Bruno
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