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tony draper
12th May 2012, 22:09
We have all seen this clip or one like it it has been posted a few times,
The Biggest Stars in the Universe - YouTube,
Just watched it again and a thunk struck,star formation ie a collapsing ball of dust and hydrogen becomes so dense and hot under its own gravity that it cause the old fusion magic to occur and eurika! we have a star, a ball of matter whos internal thermo nuclear reaction is try to blow apart whilst being prevented doing so own gravity,
Now being that these proccesses are the same every where in the universe,how come there are such giant stars? I do not mean large because they are coming to the end of their lives and will swell up to red giant size as our own sun will do,but seem to have started out millions of times larger or more massive than our sun.
Why didn't they just light up the same as our sun when the same amount of matter had collapsed under gravity?,how come they just kept on growing?
:confused:

Sprogget
12th May 2012, 23:01
Some v interesting stuff on high mass stars here for ponderance and metaphorical beard stroking.:cool:

Stellar Evolution: High-Mass Stars (http://www.ucolick.org/~bolte/AY4_00/week8/massive_stars.html)

tony draper
12th May 2012, 23:20
One shall peruse that in detail on the morrow thank you Mr Sprogget,one's head tends to spin down after 10pm
:rolleyes:
One gets the jist though,big stars are just lots of stars one inside each other the inner hotter ones fusing heavier elemnts than the outer ones,one shall have to give the matter some though.
:)

Slasher
13th May 2012, 02:31
To answer your question Drapes - as best I can - it has to do
with the initial core temperature of any pubescent sun before
the thermo whatsits begin, akin to a furnace and a camp fire.

The Sun formed through hot gasses which is why its the way
it is. The more massive suns were formed with cold gas which
meant they needed more mass before gravity exerted enough
pressure to generate the heat required for "ignition". Its a bit
more complicated than that but that's the guts of it.

The next logical question "why is there hot and cold gas?" has
its roots in Big Bang and String Theory.

Matari
13th May 2012, 05:53
Apologies if this has been posted before, but worth a look:

http://htwins.net/scale2/scale2.swf?bordercolor=white

(make sure you scroll in and out)

Slasher
13th May 2012, 07:42
Yep....been posted before Mat but I never tire at watching it
from the observable Universe right down to your Max Planck
natives lurking in the nether regions of the yoctos.

probes
13th May 2012, 08:23
an undergraduate of mine claimed science is basically no different from religion (=both believe things are so), as even the theory of gravitation can't be proved properly. Convincingly.

Me being a philologist - well, I don't know. Does anybody?

Slasher
13th May 2012, 23:52
Science is self-correcting whereas religion isn't. Religion is
based on words of authority and never challenged, whereas
Scientific theory through endeavor are continually challenged.

Pseudo-sciences such as Fong Shui and global warming for
example had their roots in the scientific endeavor, but both
were hijacked by the political interests of their times. Politics
& Science throughout history have never ever been mutually
exclusive (although Galileo would testify they should). Same
goes for religion.

mister hilter
14th May 2012, 00:56
Philosophy is questions that may never be answered. Religion is answers that may never be questioned.

Loose rivets
14th May 2012, 01:52
The forces inside suns seem frighteningly powerful, but then, we are beings that perceive some virtually empty space as solid. Just how can we measure its real worth?

Binary stars? There were a lot, but they tend to eat each other, so we're left with rather less.

What is fascinating is gravity's limited ability to power fusion to do alchemy. After that, it seems stars must go into sacrificial mode to make the heavier elements.

Oooo . . . dinner. I'm going to take my blob of complex elements off to the kitchen. It's hungry.