Are brown dwarfs stars or planets? Boffins find evidence for proto-suns in a solar system

The discovery of two oddball brown dwarfs orbiting a giant orange star has reignited the question of whether brown dwarfs are feeble stars or bloated planets. V Ophiuchi (pronounced Nu Ophiuchi) is a large, cool K-type star surrounded by two brown dwarfs. One is 22.2 times the mass of Jupiter, and the other is even heavier at …

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Binary thinking

I know you lot all think in binary, but I'm surprised that the astronomical community does as well. Are they planets or stars? Why not have lots of categories? Spherical things range from very big down to quite small, and different size ranges have different properties.

Who says all brown dwarves form in the same way? There are at least three ways to make a black hole of a given size.

The universe may not be an either/or sort of place.

Take that, Occam!

[Michael H.F. Wilkinson]

Re: Binary thinking

Precisely. Some brown dwarfs may form like planets, others like stars. What dictates their properties is most likely just how much matter clumped together, not how it clumped together

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Bloody astronomers

Upvote for (astronomically) correct plural of dwarf.

[Mr Benny]

Re: Bloody astronomers

Its the correct plural full stop. Tolkien deliberately spelt it "dwarves" and his spelling caught on.

[jmch]

Re: Bloody astronomers

"Tolkien deliberately spelt it "dwarves" "

So did Snow White

[Mr Benny]

Re: Bloody astronomers

Unlikely given the original was in German and the Disney film didn't either.

[Anonymous Coward]

Re: Bloody astronomers

I see the knifes are out

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Bloody lexicographers

Well, every day is a learning day on the Interwebs. First place I ever saw the word "dwarves" was in The Hobbit in about 1965. I guess it stuck.

Also, bloody Anglo-Saxon professors with a Finnish fetish.

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Bloody UNIX

I suppose the plural of ELF is ELFs as well?

[Doctor Syntax]

Re: Bloody UNIX

....and the plural of knife is knifes?

[steelpillow]

Re: Bloody lexicographers

Tolkien's friend and fellow "Inkling" CS Lewis spelled it "Dwarfs" in his Narnia stories. That was the conventional spelling but Tolkien chose to differ, in part because his Dwarves were specifically not the dwarfs of traditional fairy tales, or short humans with primeval dwarfism or anything familiar.

I am sure that before long, the borderline between accretion and gravitational instability will be recognised as a semantic one - a core accretes from a cloud, a cloud collapses into a core.

Perhaps soon some astronomically nerdy soul will come to distinguish the accreted Brown Dwarfs from the gravitationally collapsed Brown Dwarves. Or maybe get into a flame war over it being the other way round.

[TVU]

Re: Binary thinking

"What dictates their properties is most likely just how much matter clumped together, not how it clumped together"

I am not too happy with the current ambiguous definitions of brown dwarfs and sub-brown dwarfs. I would much prefer something defined and clear cut based on their internal processes: Can the object undergo thermonuclear fusion of deuterium at the core (a brown dwarf) or not (just a large Jupiter)?

Other views are available but I think the category of sub-brown dwarf is completely pointless - it's either a brown dwarf that can experience deuterium fusion or it's just a large planet.

[MyffyW]

Re: Non-Binary thinking

Welcome to the spectrum Brown Dwarf, shine* you fabulous anomaly!

[*well glow a sort of lukewarm umber colour]

[LenG]

Surrounded

I find it difficult to comprehend how a large star can be surrounded by two brown dwarfs. Surely orbited is a more appropriate description.

[Rich 11]

Re: Surrounded

How about outflanked?

[Doctor Syntax]

Re: Surrounded

Ambushed?

Trapped?

[TeeCee]

Re: Surrounded

"Surrender, we have you surrounded!"

"Bugger. There must be two of them..."

[Claptrap314]

Since when is a 0.1% mismatch "stable"? They are most definitely NOT stable (yet). Anyone have an orbital simulator to work out how much longer to lock?

[Anonymous Coward]

V ≠ ν

v ≠ ν

Nu is a character from the Greek alphabet. It's not the same as a V from the Latin alphabet.

The quoted piece in the article got it correct, but the earlier prose failed miserably.

[phuzz]

If you can't be bothered to find whatever character map software your OS has, just go to a search engine and search for "greek letter nu", and copy paste from there. ν

(I do this every time I need to use the € symbol)

[Crisp]

Re: copy paste from there

I do this for every character I need to use.

[imanidiot]

Alt+0128 => €. I need that often enough to know it of the top of my head.

[Loyal Commenter]

Ctrl+Alt+4 => €

It's even marked on most keyboards, assuming you're not using another OS™

(that one's Alt+0153...)

[Spherical Cow]

I guess Windows 10 must count as "another OS" because Ctrl+Alt+4 does nothing for me.

[phuzz]

Works for me on Win 10, what language is your keyboard set to? (I'm on en-gb)

[Arthur the cat]

Nu is a character from the Greek alphabet.

And the Greek capital ν looks like Latin capital N, not V.

[Teiwaz]

brown dwarf

I always thought those were those little slightly carbonised little floaters you find in public lavies that won't go down after two flushes.

And you know if you leave the next person waiting to use the cubicle with think it your fault...

[Anonymous Coward]

In order to avoid confusion I suggest:

- undersized star => brown dwarf

- oversized planet => brown giant

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Categorisation

Excellent idea.

What are your views on what we should call planets expelled from solar systems, since they aren't orbiting a star any more?

Also, some clarification on what to call the Pluto system. If Pluto is a dwarf planet, are Charon and the rest dwarf moons? Or would the smaller ones be moonlets or maybe dwarf moonlets? Or dwarflet moons? Or dwarf planet moonlets?

[Crisp]

Re: what we should call planets expelled from solar systems

Intergalactic and planetary?

We should call them Beastie Boys.

[Anonymous Coward]

Re: Categorisation

- expelled planets => stroppy teenagers ?

- undersized planet => grey dwarf

- oversized moon => grey giant

- undersized moon[*] => moonlet

[*] i.e. too small/dim to be worth trying to find a rhyme for

[Toni the terrible]

Re: Categorisation

I have been told thast the word planet meant 'wanderer' originally

[Anonymous Coward]

Hmmm

I sh*t out two particularly stubborn brown dwarfs this morning.