Stars don't "evolve" (APOD 12 Nov 2006)

Comments and questions about the APOD on the main view screen.
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BMAONE23
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Post by BMAONE23 » Fri Jan 26, 2007 1:46 am

Just a little fuel for the fires: If first series stars formed from the condensing of primordial hydrogen within a few 100my of the BB, exactly how much hydrogen is necessary? This image from Hubble http://antwrp.gsfc.nasa.gov/apod/ap070125.html certainly indicates mass quantities of the stuff just floating around out there. It would seem to me that there will, at some point in time, be an abundance of stars that might alter the appearance of this famous hunter. Unless they are all to become even smaller less noticeable stars than what we see today.

harry
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Post by harry » Fri Jan 26, 2007 3:07 am

Hello All

iamlucky said
Well, discussions about the validity of the big bang theory have already been given a pretty thorough exercise here, so I don't intend to continue that. However, I subscribe to the mainstream acceptance of the BBT as the best guess we currently have for the formation of the universe.
The main stream is no longer the main stream. The BBT is not the best guess for the formation of the universe. But nobody will stop you in thinking along those lines.

That said, I maintain my position on the ability of a gas to condense into a star, although as I consider it further, it should be possible irregardless of the Big Bang Theory.
A star usually will require a gravity sink to form on. Normal Hydrogen clouds will not form a star.

Harry, I'm interested in a general summary of your theories on the universe. I know you've linked to some lengthy papers suggesting the sun has a mostly iron core and that elliptical galaxies are older than we think, but I'm more interested in your theory on the origin and age of the universe and star formation. It will help me better understand some of your posts.
I think that the universe is endless and matter is spread throughout.
The parts within the universe are recycling, colliding and doing their thing.

Observations and research into compact stars and Ultra dense degenerated plasma matter (Blackholes) and their workings are the KEYS to the recycling process.

We also notice that parts of the universe expand as in supernova to nebulae to many light years.

We aslo notice the movement to clusters.

As for the expanding universe, I do not think it is expanding. This is part of the ad hoc ideas of the Big Bang theory.
Harry : Smile and live another day.

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iamlucky13
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Post by iamlucky13 » Fri Jan 26, 2007 9:14 pm

Thanks for that summary. I see a little more of your perspective now.
harry wrote:
That said, I maintain my position on the ability of a gas to condense into a star, although as I consider it further, it should be possible irregardless of the Big Bang Theory.
A star usually will require a gravity sink to form on. Normal Hydrogen clouds will not form a star.
The fact that it is a cloud implies that it is a region of higher density than the surrounding space. If so, there is more mass per volume there, and therefore more gravity. This is the gravity sink in this scenario. There is a net tendency toward the center of the cloud.

Of course, if there is too much uniformity in the gas density, the net gravitational effect is insufficient to collapse a region down into a star. The gas may just sit there doing nothing forever, or it may wait for a disturbance to it's uniformity, such as a shockwave from a supernova or a massive object like a star cluster or galaxy passing nearby.

So, depending on how the gas is distributed, this could take a really long time.
"Any man whose errors take ten years to correct is quite a man." ~J. Robert Oppenheimer (speaking about Albert Einstein)

harry
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Post by harry » Sat Jan 27, 2007 3:28 am

Hello iamlucky

You could be right mate.

But alot of these nebulae are surrounded by many compact star cores like dwarf stars that maybe rejuvinated by the matter in these clouds.

As for a gravity sink you need some form of density such as a compact core to provide the gravity sink.

Everybody may give an opinion. Right or wrong because we are in a field where its anybodies court.
Harry : Smile and live another day.

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