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Are brown dwarf planets even planets?


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Now before you ask, I know this isn't the right place to discuss this, but I just wanted to know, are brown dwarf planets planets? Because for a planet to be a planet it needs to orbit a star, if it orbits a planet, it's a moon. But brown dwarfs aren't planets, nor are they true stars. So would a planet around a brown dwarf be a planet, a dwarf planet , or a moon? (Let's say the hypothetical "planet" meets all other conditions for being a planet.)

Also I know what a Brown Dwarf is. Don't tell me that stuff because I already know it.

On some Brown Dwarfs it rains iron.

Edited by electricpants
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Oh great, we need ANOTHER planet subclass? The Pluto backlash was bad enough, now we need yet another confusing set of rules.

I suggest we call all celestial objects "Space rocks" along with a description of what it's like. Asteroid and the like would be "Small space rocks". Planets and dwarf planets would be "Big space rocks". Gas planets would be "Space balloons". Stars would be "Space lights". What we call a red dwarf would be a "Small red space light". Our sun would be a "Small yellow space light". Rigel would be a "Big blue space light". Neutron stars would be "Scary hard space lights" and black holes would be called "AAAAAAAAAA". Wouldn't that be way simpler? We're overthinking this whole nomenclature thing.

Edited by cubinator
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10 minutes ago, cubinator said:

Oh great, we need ANOTHER planet subclass? The Pluto backlash was bad enough, now we need yet another confusing set of rules.

I suggest we call all celestial objects "Space rocks" along with a description of what it's like. Asteroid and the like would be "Small space rocks". Planets and dwarf planets would be "Big space rocks". Gas planets would be "Space balloons". Stars would be "Space lights". What we call a red dwarf would be a "Small red space light". Our sun would be a "Small yellow space light". Rigel would be a "Big blue space light". Neutron stars would be "Scary hard space lights" and black holes would be called "AAAAAAAAAA". Wouldn't that be way simpler? We're overthinking this whole nomenclature thing.

You need to get this to the IAU :D

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1 hour ago, cubinator said:

Oh great, we need ANOTHER planet subclass? The Pluto backlash was bad enough, now we need yet another confusing set of rules.

I suggest we call all celestial objects "Space rocks" along with a description of what it's like. Asteroid and the like would be "Small space rocks". Planets and dwarf planets would be "Big space rocks". Gas planets would be "Space balloons". Stars would be "Space lights". What we call a red dwarf would be a "Small red space light". Our sun would be a "Small yellow space light". Rigel would be a "Big blue space light". Neutron stars would be "Scary hard space lights" and black holes would be called "AAAAAAAAAA". Wouldn't that be way simpler? We're overthinking this whole nomenclature thing.

Yes! Let's make the Randall Munroe way the primary way!!!

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9 hours ago, electricpants said:

Now before you ask, I know this isn't the right place to discuss this, but I just wanted to know, are brown dwarf planets planets? Because for a planet to be a planet it needs to orbit a star, if it orbits a planet, it's a moon. But brown dwarfs aren't planets, nor are they true stars. So would a planet around a brown dwarf be a planet, a dwarf planet , or a moon? (Let's say the hypothetical "planet" meets all other conditions for being a planet.)

According to the IAU, yes and no. Many orbit stars, and the so they are planets. They definitely dominate their region of space and are very spheroidal. But the the ones which don't orbit stars, no. 

But that's according to the IAU.

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57 minutes ago, Andem said:

Yes! Let's make the Randall Munroe way the primary way!!!

Can you tell I read a lot of xkcd? :P Seriously, though, I vote that the next black hole to be discovered be named "AAAAAAAAAAAA". It's a perfectly fitting name for such a freaking scary object.

Edit:

Sagittarius AAAAAAAAAAAAAAA*

Edited by cubinator
That pun will suck you up *badum tsh*
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8 hours ago, oglommi said:

A brown dwarf is  a failed star. A substellar object with not enough mass to start hydrogen fusion.

I know what they are (they are actually my favorite type of star-like object), I'm just wondering what planet-like bodies around them would be classified as. (I'll go to bed now. Don't reply until tomorrow.)

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2 hours ago, cubinator said:

Oh great, we need ANOTHER planet subclass? The Pluto backlash was bad enough, now we need yet another confusing set of rules.

I suggest we call all celestial objects "Space rocks" along with a description of what it's like. Asteroid and the like would be "Small space rocks". Planets and dwarf planets would be "Big space rocks". Gas planets would be "Space balloons". Stars would be "Space lights". What we call a red dwarf would be a "Small red space light". Our sun would be a "Small yellow space light". Rigel would be a "Big blue space light". Neutron stars would be "Scary hard space lights" and black holes would be called "AAAAAAAAAA". Wouldn't that be way simpler? We're overthinking this whole nomenclature thing.

No, not that. I agree with you, i'm just asking if they're a planet, a dwarf planet, or a moon. Not asking for another planet classification.

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5 hours ago, electricpants said:

No, not that. I agree with you, i'm just asking if they're a planet, a dwarf planet, or a moon. Not asking for another planet classification.

They're planets. Rogue planets if they're not bound by a star's gravity.

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6 hours ago, cubinator said:

Can you tell I read a lot of xkcd? :P Seriously, though, I vote that the next black hole to be discovered be named "AAAAAAAAAAAA". It's a perfectly fitting name for such a freaking scary object.

Edit:

Sagittarius AAAAAAAAAAAAAAA*

What about VY Canis Majoris?

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A brown dwarf is neither a planet nor a star. It is a brown dwarf, or a sub-stellar object.

A usual definition of a brown dwarf is an object which is massive enough to, at some point, have triggered nuclear fusion inside its core, but is not massive enough to maintain it over significant amounts of time.

The IAU doesnt even bother with that:

  • < 13 MJ : Planet
  • > 13 MJ : Brown dwarf
Quote

1) Objects with true masses below the limiting mass for thermonuclear fusion of deuterium (currently calculated to be 13 Jupiter masses for objects of solar metallicity) that orbit stars or stellar remnants are "planets" (no matter how they formed). The minimum mass/size required for an extrasolar object to be considered a planet should be the same as that used in our Solar System.

2) Substellar objects with true masses above the limiting mass for thermonuclear fusion of deuterium are "brown dwarfs", no matter how they formed nor where they are located

 

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1 hour ago, Gaarst said:

A brown dwarf is neither a planet nor a star. It is a brown dwarf, or a sub-stellar object.

A usual definition of a brown dwarf is an object which is massive enough to, at some point, have triggered nuclear fusion inside its core, but is not massive enough to maintain it over significant amounts of time.

The IAU doesnt even bother with that:

  • < 13 MJ : Planet
  • > 13 MJ: Brown dwarf

 

*Sigh* This is the third person that thinks I don't know what a brown dwarf is. I know all of what you just told me. I'm asking what a planet-like body orbiting one would be considered as, because brown dwarfs aren't planets, nor are they stars. I know their mass range (13 MJ - 80 MJ) And I know how hot one can be (L Dwarfs can be in excess of 2,000 K And Y Dwarfs can be about 125 K. T Dwarfs are somewhere around 1,000 K).

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3 hours ago, Spaceception said:

What about VY Canis Majoris?

It would be a "Oh wow that's a big red space light"

Brown Dwarfs would be a "Wow that's a freakin' tiny magenta space light"

Brown Dwarfs are magenta.

Edited by electricpants
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1 hour ago, electricpants said:

*Sigh* This is the third person that thinks I don't know what a brown dwarf is. I know all of what you just told me. I'm asking what a planet-like body orbiting one would be considered as, because brown dwarfs aren't planets, nor are they stars. I know their mass range (13 MJ - 80 MJ) And I know how hot one can be (L Dwarfs can be in excess of 2,000 K And Y Dwarfs can be about 125 K. T Dwarfs are somewhere around 1,000 K).

Quote

1) Objects with true masses below the limiting mass for thermonuclear fusion of deuterium (currently calculated to be 13 Jupiter masses for objects of solar metallicity) that orbit stars or stellar remnants are "planets" (no matter how they formed). The minimum mass/size required for an extrasolar object to be considered a planet should be the same as that used in our Solar System.

2) Substellar objects with true masses above the limiting mass for thermonuclear fusion of deuterium are "brown dwarfs", no matter how they formed nor where they are located

The IAU like vaguely precise definitions (especially for brown dwarves related stuff), but for me it means that a planetary-sized body orbiting a brown dwarf would be considered a planet (as long as it fills the other criterions).

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On Saturday, May 14, 2016 at 3:29 PM, Fiddlestyx said:

A brown dwarf planet, <----- see that last word?

Same goes for Pluto, a dwarf planet, it's still a planet no matter what NDT says. :D

That isn't how language works.

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1 hour ago, NFUN said:

That isn't how language works.

Language is dynamic. It changes. According to Webster a planet is a large celestial body in a solar system. The issue here is: what "is" large? Pluto would seem large to us if we were on it. Jupiter would seem small from far away. So, depending on your interpretation of large, anything could be a planet.

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2 hours ago, Bill Phil said:

Language is dynamic. It changes. According to Webster a planet is a large celestial body in a solar system. The issue here is: what "is" large? Pluto would seem large to us if we were on it. Jupiter would seem small from far away. So, depending on your interpretation of large, anything could be a planet.

That definition is very loose. Astronomically, "large" means large enough to either capture or kick similarly sized or smaller bodies out of it's orbit. Pluto fails that definition, and thus is not a planet.

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