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Fraser
2004-Nov-18, 07:04 PM
SUMMARY: Early star formation is a bit of a puzzle for astronomers, since all the stars that we can see formed out of molecular gas and dust, which are produced in stars. How did the first ones form without any gas and dust? One class of galaxies, called Blue Dwarf Galaxies may offer some clues. They contain interstellar clouds which are similar to the material that would have been present in the early Universe. And these galaxies can have active regions of furious star formation. New research from the European Southern Observatory has targeted one of these Blue Dwarfs to try and understand the process better.

What do you think about this story? Post your comments below.

Guest
2004-Nov-18, 07:07 PM
very nice :D hope we can get more great info from this

om@umr.edu
2004-Nov-18, 07:24 PM
This is an interesting story, Fraser.

Like the chicken and the egg.

It is commonly assumed that "all the stars that we can see formed out of molecular gas and dust, which are produced in stars."

Which raises the question " How did the first ones form without any gas and dust?

The answer likely depends on deciding if "primordial material" began as

a.) Widely dispersed clouds of matter in the form of Hydrogen atoms, or

b.) Highly compressed matter in the form of Neutrons in neutron stars.

I suspect Neutrons in neutron stars preceeded widely dispersed interstellar Hydrogen. The popular opinion is that widely dispersed Hydrogen preceeded Neutrons in neutron stars.

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2004-Nov-18, 09:04 PM
It's interesting that this nearby blue dwarf galaxy can be forming so late. I suspect that it's size may be a factor. What must the Milky way and M31 looked like when they were glowing with their first stars?

I bet that the very bright infrared object in that galaxy is a heavily shrowded Supermassive Black Hole in the 100,000 Solar Mass size range.

Guest
2004-Nov-18, 09:12 PM
I suspect Neutrons in neutron stars preceeded widely dispersed interstellar Hydrogen.
How did you arrive at that conclusion?

antoniseb
2004-Nov-18, 09:22 PM
Originally posted by Guest@Nov 18 2004, 09:12 PM
How did you arrive at that conclusion?
He's an 'alternative theorist' promoting his unusual theory, but outright discussion of his theory is, for the present, not allowed here. E-mail him for more details.

om@umr.edu
2004-Nov-18, 09:45 PM
Originally posted by Guest@Nov 18 2004, 09:12 PM

I suspect Neutrons in neutron stars preceeded widely dispersed interstellar Hydrogen.
How did you arrive at that conclusion?
Some background information is on my web page

http://www.umr.edu/~om

I will be happy to reply to specific questions here or by e-mail.

om@umr.edu

With kind regards,

Oliver

om@umr.edu
2004-Nov-19, 03:12 PM
Originally posted by Guest@Nov 18 2004, 09:12 PM

I suspect Neutrons in neutron stars preceeded widely dispersed interstellar Hydrogen.

How did you arrive at that conclusion?
Hi, Guest.

Evidence for Neutron-emission from neutron stars as a natural process and major energy source is summarized in a paper, "Neutron repulsion confirmed as energy source", Journal of Fusion Energy 20 (2003) 197-201.

http://web.umr.edu/~om/abstracts2003/jfe-n...-neutronrep.pdf (http://web.umr.edu/~om/abstracts2003/jfe-neutronrep.pdf)

Following neutron emission,

<n> --&#62; n + 10-22 MeV

Neutrons decay to Hydrogen atoms,

n --&#62; H (half-life = 11 min)

and H fills interstellar space.

Compact objects are found at galactic centers and may occur at the centers of ordinary stars.

With kind regards,

Oliver
http://www.umr.edu/~om

VanderL
2004-Nov-19, 09:13 PM
How Did the First Stars Form?

The same as they do today, star formation now isn&#39;t any different from star formation in earlier epochs, all the components are in place, the only problem is that our models are inadequate for describing how stars form. So, if we know how one star forms, than that&#39;s the answer.

Cheers.

Greg
2004-Nov-20, 02:31 AM
This an excellent piece for discussion. Here we have a nearby example of a microcosm of what happened in the early days of large galaxy formation. There is even fodder here for "steady state" enthusiasts in that we see a new galaxy forming just like all the others so long after the big bang. I think that most likely the phenomenon is not only mass dependent, but density dependent. Perhaps in a relatively isolated area of sapce a relatively diffuse,sparse, and relatively unstirred cloud needed longer to get itself together to form the fist supermassive star. Only when this went supernova and dispersed its elements did enough star forming clusters mature to the point that we coul spot it and identify the structure as a blue dwarf galaxy. A more interesting finding would be to catch one of these supermassive progenitor stars in the act of supernovaing or spot it in the midst of a cloud before it did so (Spitzer may be able to do this)[COLOR=blue][COLOR=blue][COLOR=blue]. Perhaps such objects are sources of gamma ray bursts that we may not have considered (especially those not associated with host galaxies,). Very exciting stuff.

om@umr.edu
2004-Nov-27, 05:23 PM
Originally posted by VanderL@Nov 19 2004, 09:13 PM

How Did the First Stars Form?

. . . if we know how one star forms, than that&#39;s the answer.

Right on, VanderL.

That&#39;s why we must study the star next door and figure out how it formed &#33;

With kind regards,

Oliver
http://www.umr.edu/~om

antoniseb
2004-Nov-27, 06:02 PM
Originally posted by om@umr.edu@Nov 27 2004, 05:23 PM
That&#39;s why we must study the star next door and figure out how it formed &#33;
It seems to me that it would be better to watch stars forming rather than one that has already formed if we want a better idea of the process of creation. The star we have handy is pretty good for giving us clues as to how a mature one operates.

om@umr.edu
2004-Nov-27, 06:17 PM
Originally posted by antoniseb@Nov 27 2004, 06:02 PM

It seems to me that it would be better to watch stars forming rather than one that has already formed if we want a better idea of the process of creation. The star we have handy is pretty good for giving us clues as to how a mature one operates.
I partly agree, Anton.

The star next door gives us clues as to how a mature star operates.

But I doubt if watching distant stars form tells as much as detailed measurements on the Sun.

Our disagreement is explained in the Iron Sun discussion.

http://www.universetoday.com/forum/index.p...pic=2544&st=855 (http://www.universetoday.com/forum/index.php?showtopic=2544&st=855)

With kind regards,

Oliver
http://www.umr.edu/~om

VanderL
2004-Nov-27, 06:50 PM
It seems to me that it would be better to watch stars forming rather than one that has already formed if we want a better idea of the process of creation.

Missed that one, that would be wonderful, but looking for the creation of a new star means that you have to make certain assumption on how thet are created in the first place. I think it is very difficult, if not impossible to detect the first steps of star formation (accretion). Then comes the next critical step, what makes a star shine. The process of shining is more easily detectable, light starts to be emitted. But that doesn&#39;t tell us anything about the mechanism, is a flaring object a star, how do we measure it&#39;s mass, we don&#39;t even know what makes a star a star, how about "brown dwarves, and all those questions. I think we can learn more by studying our own "ball of light" in detail. Understanding what a star is, tells us exactly how it must have formed. And by all accounts, we have a lot to learn.

Cheers.

Mike525
2004-Nov-27, 10:40 PM
Originally posted by fraser@Nov 18 2004, 07:04 PM
Early star formation is a bit of a puzzle for astronomers, since all the stars that we can see formed out of molecular gas and dust, which are produced in stars.
Molecular gas and dust can also be formed in intergalactic regions by way of cosmic ray decay (source is the all pervasive CBR-cosmic background radiation) and atom building processes

How did the first ones form without any gas and dust?
Again, intergalactic regions are a source of vast dust clouds that condense into stellar clusters which then form dwarf galaxies which eventually accrete more clusters and become the larger spirals and ellipticals.

One class of galaxies, called Blue Dwarf Galaxies may offer some clues. They contain interstellar clouds which are similar to the material that would have been present in the early Universe. And these galaxies can have active regions of furious star formation.
Some protoclusters get cannabalized by galaxies before they fully condense as this indicates.

Anyone here going to Geoff Marcy&#39;s lecture at Cornell this week?

Mike

om@umr.edu
2004-Nov-27, 11:27 PM
Originally posted by Mike525@Nov 27 2004, 10:40 PM
Anyone here going to Geoff Marcy&#39;s lecture at Cornell this week?

Thanks, Mike525,

I can&#39;t go to Cornell. If you go, please ask Prof. Marcy if he has any more thoughts on the reason why so many “Maunder minimum” stars appeared iron-rich in his survey:

http://www.berkeley.edu/news/media/release...1_maunder.shtml (http://www.berkeley.edu/news/media/releases/2004/06/01_maunder.shtml)

With kind regards,

Oliver
http://www.umr.edu/~om

Duane
2004-Nov-28, 11:51 AM
Well don&#39;t ask him that or he&#39;ll just stare blankly at you.

Ask him why there are so many metal rich stars in his survey. Or ask him how the stars once thought to be examples of Mander minimum stars were so badly misidentified.

Better yet, ask Jason Wright. Also ask Jason how his paper describing the activity of the metal rich stars is coming along. Well, assuming he is with Proff Marcy at this conference. This is especially so given that Jason was the actual author, not Marcy.

Oliver, are you having problems with your memory?

om@umr.edu
2004-Nov-28, 04:45 PM
Originally posted by Duane@Nov 28 2004, 11:51 AM
Oliver, are you having problems with your memory?
Hi, Duane.

Personal slams do not advance understanding.

Can&#39;t we disagee without being disagreeable?

Oliver
http://www.umr.edu/~om

antoniseb
2004-Nov-28, 04:54 PM
Originally posted by om@umr.edu@Nov 28 2004, 04:45 PM
Personal slams do not advance understanding.
Neither does ignoring valid refutation of what you&#39;ve posted repeatedly.
I think Duane might have asked about your memroy more politely, but it was a direct statement that your command of the facts does not seem as solid as you project them to be. This particular case just happened to stand out at the moment.

om@umr.edu
2004-Nov-28, 05:28 PM
What indicated memory loss or loss of the command of the facts in my request to

" . . . please ask Prof. Marcy if he has any more thoughts on the reason why so many “Maunder minimum” stars appeared iron-rich in his survey ?

http://www.berkeley.edu/news/media/release...1_maunder.shtml (http://www.berkeley.edu/news/media/releases/2004/06/01_maunder.shtml)

What&#39;s up ?

Why the unpleasantness ?

With kind regards,

Oliver
http://www.umr.edu/~om

Mike525
2004-Nov-28, 11:47 PM
Originally posted by Duane@Nov 28 2004, 11:51 AM
Ask him why there are so many metal rich stars in his survey. Or ask him how the stars once thought to be examples of Mander minimum stars were so badly misidentified.
I&#39;ve read some of his (Marcy et al) papers and am interested in the validity of the proposed metalicity correlation to probable exoplanet stars. Since they are measuring metalicity coming from the photoshere and/or chromosphere I would think that indicates a metal rich environment which the star is in and it&#39;s accreting the surrounding material. Does this suggest a protoplanet disk region or the last remnants of one and now the star and planets have cleared most of it away?

I noticed some exoplanet stars are not metal rich at all so maybe that solar system is older. Another variable is, again, what kind of region the star is moving through.

It sounds like the Maunder effect is too anomalous to see a pattern yet and my focus is on the properties of exoplanet stars at this conference. But, if you see a link let me know.

om@umr.edu
2004-Nov-29, 01:39 AM
Originally posted by Mike525@Nov 28 2004, 11:47 PM
It sounds like the Maunder effect is too anomalous to see a pattern yet . . .
Hi, Mike.

There is a hint that metalicity depends on the level of magnetic activity.

If true, metalicity of the Sun may follow solar cycles - the long-term one that produced the "Maunder Minimum" and perhaps even produce a detectable variation over the short-term 11-year cycle.

With kind regards,

Oliver
http://www.umr.edu/~om

Duane
2004-Nov-29, 07:02 PM
Hi, Duane.

Personal slams do not advance understanding.

Can&#39;t we disagee without being disagreeable?



I think Duane might have asked about your memroy more politely,


What indicated memory loss or loss of the command of the facts in my request to

" . . . please ask Prof. Marcy if he has any more thoughts on the reason why so many “Maunder minimum” stars appeared iron-rich in his survey ?

Oliver, it was not a personal slam, it was a legitimate question. I did not intend it to be impolite, although I did intend it to be rhetorical.

Why the question? Because I have pointed out to you that Wright&#39;s paper does not say anywhere in it that Maunder Minimum stars are iron rich, a fact that Mr Wright himself came by to post in confirmation. I have pointed that out to you at least 3 times, and I have directly quoted Mr Wright at least twice.

It gets a bit tiring to have to repeat it again and again. It suggests that maybe you have forgotten the past posts.

antoniseb
2004-Nov-29, 07:11 PM
Originally posted by Duane@Nov 29 2004, 07:02 PM
It suggests that maybe you have forgotten the past posts.
Or simply prefer to ignore them, which is terribly impolite, and unconvincing as a debating technique. Hence the long overdue expression of irritation.

Duane
2004-Nov-29, 10:07 PM
Originally posted by Mike525+Nov 28 2004, 11:47 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (Mike525 @ Nov 28 2004, 11:47 PM)</td></tr><tr><td id='QUOTE'> <!--QuoteBegin-Duane@Nov 28 2004, 11:51 AM
Ask him why there are so many metal rich stars in his survey. Or ask him how the stars once thought to be examples of Mander minimum stars were so badly misidentified.
I&#39;ve read some of his (Marcy et al) papers and am interested in the validity of the proposed metalicity correlation to probable exoplanet stars. Since they are measuring metalicity coming from the photoshere and/or chromosphere I would think that indicates a metal rich environment which the star is in and it&#39;s accreting the surrounding material. Does this suggest a protoplanet disk region or the last remnants of one and now the star and planets have cleared most of it away?

I noticed some exoplanet stars are not metal rich at all so maybe that solar system is older. Another variable is, again, what kind of region the star is moving through.

It sounds like the Maunder effect is too anomalous to see a pattern yet and my focus is on the properties of exoplanet stars at this conference. But, if you see a link let me know. [/b][/quote]
A few thoughts Mike.

It seems that many of these stars studied by Wright et al were actually formed in a metal-rich enviroment. It seemed odd (well, to me at least) considering that many of the stars were said to be older and approaching their red-giant phase.

Wright clarified that somewhat, saying that there was a possibility the stars were either metal rich or older. He explained that he came to be able tell the difference because the metal rich stars, while initally appearing to be inactive, actually weren&#39;t. He didn&#39;t go into further detail about why that was the case, saying that he has a new paper he is working on to explain it.

He went on to explain that the older stars were not in a Mander minimum, they were dead. In his paper, they confirmed that those older sun-like stars were on the order of 9.5 Byo on average, or about twice the age of the sun. If anything, his work seems to confirm our current understanding of the mechanism by which stars age.

On the subject of the proto-planetary disc, it really isn&#39;t addressed by Marcy or Wright in this paper. Intuitively, I would say probably not--that is to say, the planets (if any) are fully formed and the protoplanetary disc is long gone. There may be something more about this from Wright as it relates to the metal-rich stars, although I think he is saying that even these metal-rich stars are about equal to the age of the sun. Assuming that to be the case, again, the protoplanetary disc should be long gone.

As you say, it seems like there are many more exoplanets around the metal rich stars, but I wonder if this is because of our identification techniques combined with the type of planet that would form around a metal-rich star vrs a metal-medium star like our sun. Is it the case that metal rich stars form bigger planets closer in, thus skewing our indetification techniques towards those types of stars? I guess time will tell.

Have fun at the conference, wish I could be there :)

Algenon the mouse
2004-Nov-30, 01:43 AM
Didn&#39;t a supercomputer figure out that the first stars where huge? (I believe a 100 times the size of our own sun).

That would cause them to burn brightly, but be short lived.

om@umr.edu
2004-Nov-30, 03:33 AM
That is the prevailing view.

But I don&#39;t know that a supercomputer figured out that the first stars where huge.

I suspect this was assumed because:

a.) Large stars evolve quickly,

b.) The early universe is assumed to be mostly H, and

b.) Nucleosynthesis products, like iron (Fe), are observed in the early universe.

With kind regards,

Oliver
http://www.umr.edu/~om

Scarla O'
2004-Nov-30, 10:19 AM
Originally posted by Duane@Nov 28 2004, 11:51 AM
"Oliver, are you having problems with your memory?"

I&#39;m sorry but i always assumed the job of a moderator was to remain professional at all times? No one can seriously believe that you mean that question sincerely.

I know that the ongoing debate re. the Iron Sun and its methodology frustrates some of you but Professor Manuel has been nothing other than polite.

(If you find Professor Manuel&#39;s approach irksome then you can ignor it).

Duane
2004-Nov-30, 08:02 PM
No one can seriously believe that you mean that question sincerely.


Nor did I say I did. I admitted it was rhetorical. Still, I do wonder often, as he continually forgets about proofs and corrections already made in the discussions we have with him. At least I prefer to think he forgets, because the alternative is that he purposefully ignores them.


I know that the ongoing debate re. the Iron Sun and its methodology frustrates some of you but Professor Manuel has been nothing other than polite.


I can&#39;t believe you really believe that. He has been churlish, condescending, high-browed, and down right insulting to every person who has sought evidence or explanations regarding his theory.


(If you find Professor Manuel&#39;s approach irksome then you can ignor it).


Uh, no. Professor Manuel is the main, maybe only, proponant of a very controversal and generally unaccepted theory. His use of scientific jargon, graphs, diagrams and equations seems intended to convince the vast majority of amateures who cannot or will not plow through the jargon or actually do the calculations that his theory is somehow accepted by the mainstream.

Worse, he uses these same tactics in other threads in a manner that would suggest to the uninitiated that they are given facts, and not poorly supported conclusions.

As long as I remain a moderator on this board I will not sit idely by while he makes such pronouncements. I will, each and every time, insert a correction when I see it necessary.

om@umr.edu
2004-Dec-01, 05:16 PM
Originally posted by Duane@Nov 30 2004, 08:02 PM
Uh, no. Professor Manuel is the main, maybe only, proponant of a very controversal and generally unaccepted theory. His use of scientific jargon, graphs, diagrams and equations seems intended to convince the vast majority of amateures who cannot or will not plow through the jargon or actually do the calculations that his theory is somehow accepted by the mainstream.

Worse, he uses these same tactics in other threads in a manner that would suggest to the uninitiated that they are given facts, and not poorly supported conclusions.

As long as I remain a moderator on this board I will not sit idely by while he makes such pronouncements. I will, each and every time, insert a correction when I see it necessary.
Duane,

Scarla O&#39; is correct in noting the need for professionalism.

You need not agree with my conclusions, which may be wrong, but that does not excuse:

a.) Personal insults

b.) Inserting your oninion inside my postings

c.) Deleting my figures to protect "amateures"

The word "amateur" comes from the Latin word amator for "lover". Amateures do not need your protection. Their interest in science is based on a love for truth.

Why shouldn&#39;t Mike525 " . . . ask Prof. Marcy if he has any more thoughts on the reason why so many “Maunder minimum” stars appeared iron-rich in his survey ?"

http://www.berkeley.edu/news/media/release...1_maunder.shtml (http://www.berkeley.edu/news/media/releases/2004/06/01_maunder.shtml)

Before Professor Geoffrey Marcy&#39;s survey was completed, Professors Barry W. Ninham, Stig E. Friberg, and I published a professional scientific paper concluding that solar magnetic fields:

a.) Accelerate H+ ions upward

b.) Maintain mass separation in the Sun

c.) Cause intermittant changes that disrupt our climate

See "Superfluidity in the Solar Interior: Implications for Solar Eruptions and Climate", Journal of Fusion Energy, vol. 21 (2003) pages 193-199.

The observations of Wright and Marcy seemed to fit our suggestion that solar magnetic fields cause solar mass separation. That may annoy you, but

Universe Today forum is not the moderator&#39;s selection of information for "amateures".

With kind regards,

Oliver
http://www.umr.edu/~om

Duane
2004-Dec-01, 06:07 PM
You need not agree with my conclusions, which may be wrong, but that does not excuse:

a.) Personal insults

b.) Inserting your oninion inside my postings

c.) Deleting my figures to protect "amateures"

The word "amateur" comes from the Latin word amator for "lover". Amateures do not need your protection. Their interest in science is based on a love for truth.

Why shouldn&#39;t Mike525 " . . . ask Prof. Marcy if he has any more thoughts on the reason why so many “Maunder minimum” stars appeared iron-rich in his survey ?"


a.) Oliver, go back and read what I have said again, then show me where I have made a personal insult.

I have suggested your approach is unethical, I have suggested your methods are pseudoscientific, I have questioned your understanding of various disiplines, I have questioned whether you remember past conversations, and I have pointed out your thinly-veiled insults and arrogence.

I have not called you a name, I have not questioned your nationality, manhood, patriotism, ability, intellegence, credentials, training, education, or anything else along those lines. I have called your theory and your pseudoscientific approach to presenting your theory into question, but I have never called you anything except grumpy old man, which you named yourself before I ever used it.

Please, show me where I have made a personal insult.

You, on the other hand, have insinuated that I am a child, have child-like intellegence, am uneducated, and am not worth listening to because I am an unpublished nobody. You even accused me of not supporting charities. Who is using personal attacks here Oliver?

b.) I did that just to save time. I colored it to ensure no one would mistake those comments for you, and I added my name to the edit line to ensure everyone would know it was me. What&#39;s the big deal?

You didn&#39;t answer them, by the way.

c.) I have never deleted a figure. I have deleted your diagram of the supernova from the Iron Sun discussion because you have placed it in there 12 or more times already. I deleted the cradle of the nucleotides for the same reason, plus the fact you linked to the same diagram once already in that post. It did nothing to change or alter in any way what you were saying.

Mike should not ask Prof Marcy that question because Prof Marcy did not write the paper, the paper did not discuss Maunder Minimum stars except to say that they had been misidentified, and the actual author of that paper posted right here in these forums that the metal rich stars they studied were not inactive. Mike would have looked like an idiot.

You even admitted in these forums Oliver, that the interpretation that Maunder Minimum stars were iron rich was made by you alone, and was not made by Jason Wright in his paper.

Finally Oliver, it is "love for truth" that started me on this road of understanding your theory. At every turn I have provided solid, real research which contradicts or calls into question assertions that you have made in relation to the possibility that there is an iron core in the sun. If you don&#39;t ignore the research, you claim that it is unworthy of attention because it comes from me, a non-researcher.

The worse part is, at least at first, I expected you to provide counterpoints. That you didn&#39;t tells me that you really don&#39;t know what the hell you are talking about.

There Oliver--that&#39;s personal.