is saturn a failed sun

[sparkyjon]

not sure if this has been covered before , but i was watching something on youtube the other day (i have a broken ankle and anything is worth watching to keep me from going insane)

there was talk of Jupiter being a failed star " a brown star " ?????? never heard of one myself.

anyone think this is a possibility? i forget the video and who stated it , but it was one the well know theoretical physicist....

sorry for the life of me i dont know why i titled it saturn probably because i was just watching a documentary on it on netflix..

could a mod or admin change my title to jupiter ??

[DaveS]

No, and neither is Jupiter, far too small. We know of exoplanets much larger than Jupiter, and they're not failed stars either.

[Auntystatic]

nope not a chance and jupiter is bigger than saturn, but both are way too small to start fusion

[Macavity]

See above! <wibble> In film "2010", Arthur C Clarke (others?) imagined a "Jupiter Sun".

Jimi Hendrix (world's greatest guitarist) based Albums on it! For "officianados" only?

[SnakeyJ]

cheers Macavity - on the hendrix link, a video I'd not previously seen and a great blast/interlude from the afternoon's toils

for another astro related hendrix link I'd go for Third Stone from the Sun, from Are You Experienced -

http://www.youtube.com/watch?v=M8t1RWKCvqQ

This is the lounge isn't it?

[sparkyjon]

I wasn't talking about saturn really just a misprint in the title, i didn't think size had anything to do with it as such I thought it was the gases involved and compression involved (gravity) how big is our sun in reality as most of it is just energy being thrown up from the middle it not, who's to say how big jupiter would be if the gases ignited?, who can say what the situation was billions of years ago they think Mars once had an atmosphere and water..

I don't know I'm not clever enough to imagine or pretend i know much about whats up there and how it became what it became i should have listened in school and become and astrophysicist lol..

[JamesF]

No, and neither is Jupiter, far too small. We know of exoplanets much larger than Jupiter, and they're not failed stars either.

I think you need getting on for 100 times the mass of Jupiter to start nuclear fusion and become a genuine star. A brown dwarf marginally fails to make the grade.

James

[JamesF]

Actually, the wikipedia page has more info:

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

It says 75 to 80 times the mass of Jupiter to start hydrogen fusion and become a "proper" star, so I was a bit over the top.

James

[sparkyjon]

I think you need getting on for 100 times the mass of Jupiter to start nuclear fusion and become a genuine star. A brown dwarf marginally fails to make the grade.

James

James

ah a brown dwarf that's what it was so that isn't classed as a star then ? i'm trying to find the video i was watching but i'll be damned if i can it's probably been taken down for telling lies lol..

[Cath]

Skip to 13:40, they just babble about nothing until then ..

[sparkyjon]

this looks like an interesting read.

http://www.nasa.gov/vision/universe/starsgalaxies/brown_dwarf_detectives.html

it would seem i misunderstood what they were getting at on that video ,

[sparkyjon]

Cheers Cath that's the slowest first 12 minutes ever

[michael.h.f.wilkinson]

Several stars are roughly the size of Jupiter, but they are much denser. Jupiter does not even rate as a brown dwarf

[Ragnar]

I think something in the region of 80 times the mass of Jupiter is need to have enough gravity to get the density needed to ignite a star.

[sparkyjon]

That's the key then mass..

Thought physical size wasn't really the reason.

Isn't it a neutron star that's tiny but has loads of mass. ?.

[Ragnar]

Yes, mass and density. Neutron stars are Supernova remnants. They are what is left when a star collapses under it's own gravity, during a certain type of Supernova. They can weigh 2 0r 3 times more than The Sun, yet be about the size of a large city.

[Cath]

Isn't it a neutron star that's tiny but has loads of mass. ?.

"loads" is an understatement

A neutron star's density is the last level before blackhole'ness.

[sparkyjon]

i think i'm going to watch more and more documentaries , and read more books it's shockingly interesting.

[JamesF]

Yes, mass and density. Neutron stars are Supernova remnants. They are what is left when a star collapses under it's own gravity, during a certain type of Supernova. They can weigh 2 0r 3 times more than The Sun, yet be about the size of a large city.

Yes. Electron degeneracy pressure is what makes the difference here, I think. If the collapsing star doesn't have enough mass then the electron degeneracy pressure "holds it up" meaning the star is still composed of lots of atomic nuclei with their "sea" of electrons and huge amounts of "space" between the lot of them. If there's enough mass however, the degeneracy pressure is overcome, electrons are forced to combine with the protons to form neutrons and the entire thing can collapse an awful lot further giving an exceptionally dense star.

James

[JamesF]

Where "enough mass" is the Chandrasekhar Limit, of course. Really shouldn't forget him.

James

[emadmoussa]

Yep, failed the exams for Suns' college..

[Champagnerocker]

See above! <wibble> In film "2010", Arthur C Clarke (others?) imagined a "Jupiter Sun".

Jimi Hendrix (world's greatest guitarist) based Albums on it! For "officianados" only?

The title track of a recently released album of "lost" Hendrix material was called "Valleys of Neptune", what is far far more interesting however, is the hidden content in the "Third Stone From the Sun" song by Hendrix. Now, there are lots of urban myths regarding hidden messages in records, but in this case there actually is one, and anyone can easily hear it.

IF the speed of this record is increased from 33⅓rpm to 78rpm, which is just as easy to do if you have this on mp3 as on vinyl, then what you hear for the opening ~20seconds are radio messages exchanged between two space ships. Although they don't say anything that interesting and its just Hendrix having laughs in the studio it does brighten up what is an otherwise awful track that i generally skip over.

[Pig]

Is it not a little to close to our sun to be another one and is not our sun a lot older ?