two stellar riddles

[Helen]

Both of the following are taken from Science News of June 21, 2003. And both should be of some amusement and encouragement to young earth creationists.



First, there appear to be some very massive stars which are ‘unusually young’ very near the center of our Galaxy. “One of the stars lies as close to the galactic center as twice Pluto’s distance from the sun.” That seems far to us, but in galactic terms, that is a hair’s breadth.

This discovery is presenting two major problems to standard astronomy: first, massive stars are short-lived (“they can last no more than ten million years”), and, second, “Under ordinary conditions, no star could be born so close to a supermassive black hole.”

Were these stars formed farther out and then attracted in close?

“Since massive stars last only a few million years, they should die out long before they complete the journey inward.”

The possible solution is that star clusters were pulled into the region of the black hole, where they disrupted, thus releasing their stars. From this hypothesis, and from the idea that these star clusters must have had ‘galactic partners’ up to sixty times our sun’s mass, which might end up in an orbit around the black hole when the stars disrupted, these star clusters might be able to travel fast enough to allow their members, young and massive, to be in the region of the black hole.

OR, the stars aren’t REALLY old, claims their discoverer – they just look that way…

The article closes with this quote: “Whatever the solution to the mystery of the massive stars in the galaxy’s middle, the answer ‘is bound to be a new and incredibly interesting twist on how star formation and movement can take pace in the extreme environment surrounding a supermassive black hole.”



The second stellar riddle is posed by something called Complex H – a gas cloud “about 108,000 light-years from the Milky Way’s core, [which] stretches 33,000 light-years across, and contains 6 million suns’ worth of hydrogen gas.” What’s wrong with this?

It’s circling the Milky Way.

In a direction opposite to our galaxy’s rotation.



My comments:
The ages of stars are generally determined by the color of the stars and the amount of elements other than hydrogen and helium in them. These other elements are all referred to as “metals” by astronomers. So what we are seeing near the center of our galaxy are stars of high metal content and mass and the astronomers can’t figure how they got there. If the universe is young, however, we do not have a problem with them being there. If these ‘metals’ were formed as part of the creation process instead of being manufactured in stars (as is currently thought), then there is no reason at all why a high metal content should not be found wherever our Creator decided to put it!

As far as the gas cloud goes, if it is a satellite of our Milky Way and is ‘only’ 108,000 light years away, and if it has been there as long as they think it has, then why hasn’t it been pulled in and disrupted? Its high velocity is showing it is moving VERY quickly, but it still stands apart on its own although, as the article states, its movement is tied to that of our galaxy. The outermost layers are being torn apart by our galaxy, according to the article. So it might, also, be rather young. An evolutionary idea might be that it was traveling at high speeds through space, got ‘caught’ by the Milky Way, and then, as we are seeing now, started to be disrupted.

The problem here is that the article states its movement is tied to that of the Milky Way. That means it has been in the area long enough for that to happen. So it is not a newcomer, astronomically speaking. Yet it is only just now being disrupted, yet it is traveling in a retrograde orbit. These facts are very hard to reconcile in a long-ages scheme of things.

 

[UTEOTW]

Originally posted by Helen:
Both of the following are taken from Science News of June 21, 2003. And both should be of some amusement and encouragement to young earth creationists.

Why?

First, there appear to be some very massive stars which are ‘unusually young’ very near the center of our Galaxy... OR, the stars aren’t REALLY old, claims their discoverer – they just look that way…

I think you meant that they only look "young." That is the problem the astronomers are addressing. They are too young not too old.

Anyhow, the "they just look that way" is part of explanations on how the stars could have formed. I cannot get the original text you read but I did follow the links to the actual papers. Four possibilities are given plus another possibility in another linked paper. One reason they might look "young" is that the stars are the result of collisions of less massive stars. Less massive stars last longer and eliminate the age problem. The other possibility that gives the appearance of the wrong age is that these are one of a range of other massive objects that appear to be young massive dwarf stars.

In the other three possibilities, they are actually young stars. It is shown that the stars could have formed in situ, that they could have been stripped from a cluster of stars, and that they could have been separated from a binary. The actual answer awaits observing more of the stars orbiting close the the central black hole.

The second stellar riddle is posed by something called Complex H – a gas cloud “about 108,000 light-years from the Milky Way’s core, [which] stretches 33,000 light-years across, and contains 6 million suns’ worth of hydrogen gas.” What’s wrong with this?

It’s circling the Milky Way.

In a direction opposite to our galaxy’s rotation.

So what. The Magellanic Clouds also go the wrong way. Is this a problem? No!

from http://www.nrao.edu/pr/2003/complexh/
These results place Complex H in a small club of Galactic satellites whose orbits do not follow the rotation of the rest of the Milky Way. Among the most prominent of these objects are the Magellanic Clouds, which also are being affected by their interaction with the Milky Way, and are shedding their gas in a long stream.
Since large galaxies, like the Milky Way, form by devouring smaller galaxies, clusters of stars, and massive clouds of hydrogen, it is not unusual for objects to be pulled into orbit around the Galaxy from directions other than that of Galactic rotation.
"Astronomers have seen evidence that this accreting material can come in from wild orbits," said Butler Burton, an astronomer with the NRAO in Charlottesville, Virginia. "The Magellanic clouds are being torn apart from their interaction with the Milky Way, and there are globular clusters rotating the wrong way. There is evidence that stuff was going every-which-way at the beginning of the Galaxy, and Complex H is probably left over from that chaotic period."

So what we are seeing near the center of our galaxy are stars of high metal content and mass and the astronomers can’t figure how they got there. If the universe is young, however, we do not have a problem with them being there. If these ‘metals’ were formed as part of the creation process instead of being manufactured in stars (as is currently thought), then there is no reason at all why a high metal content should not be found wherever our Creator decided to put it!

There's no problem with the metal content of the stars. The problem is that the stars are too short lived to have an easy explanation for being where they are. I would like to hear how you explain them being where they are in your chronology. I thought you allowed for stars being formed rather than just created. If they formed, you have the same problems as the astronomers in getting them where they are, you just have less time to do it. 6000 years instead of 10,000,000 years.

As far as the gas cloud goes, if it is a satellite of our Milky Way and is ‘only’ 108,000 light years away, and if it has been there as long as they think it has, then why hasn’t it been pulled in and disrupted? [snip, read above]

Again, I do not have what you read but I do have an article from the Robert C. Byrd Green Bank Telescope where the study was conducted. There is no indication of any problems to be explained by the observations. In fact, the observations have simplified some of what was thought about Complex H.

Here is the article again. http://www.nrao.edu/pr/2003/complexh/

 

[Helen]

This response is being posted bit by bit as the full one did not load. It is by both of us, Barry and Helen:

</font><blockquote>quote:</font><hr />Originally posted by Helen:
Both of the following are taken from Science News of June 21, 2003. And both should be of some amusement and encouragement to young earth creationists.

Why?</font>[/QUOTE]Oh, I don’t know. Wishful thinking? Read on if you think more highly of us than that…

</font><blockquote>quote:</font><hr />
First, there appear to be some very massive stars which are ‘unusually young’ very near the center of our Galaxy... OR, the stars aren’t REALLY old, claims their discoverer – they just look that way…

I think you meant that they only look "young." That is the problem the astronomers are addressing. They are too young not too old.

Anyhow, the "they just look that way" is part of explanations on how the stars could have formed. I cannot get the original text you read but I did follow the links to the actual papers. Four possibilities are given plus another possibility in another linked paper. One reason they might look "young" is that the stars are the result of collisions of less massive stars. Less massive stars last longer and eliminate the age problem. </font>[/QUOTE]This is a possibility, however the metal content still marks them, in current secular understanding, as young.

The other possibility that gives the appearance of the wrong age is that these are one of a range of other massive objects that appear to be young massive dwarf stars.

In the other three possibilities, they are actually young stars. It is shown that the stars could have formed in situ,

The possibility that the stars formed in situ appeared to be discounted in the Science News article.

that they could have been stripped from a cluster of stars,

That appeared to be the option favoured by the Science News article. However, they mentioned that, given the age of the stars, there may not have been enough time for that to happen. That raises the possibility that the black hole at the centre of our galaxy may have been more massive, and hence much more active, earlier on (rather like the quasars at the frontiers of the cosmos). This would cause the stripping of the cluster to have happened more quickly at any given distance from the black hole.

and that they could have been separated from a binary. The actual answer awaits observing more of the stars orbiting close the the central black hole.

The actual problem arises because the activity of the black hole at the galactic centre precludes the formation of stars in its vicinity by currently known processes. The problem is to get massive metal rich (and hence ‘young’) stars into the vicinity of the black hole in a short time period. It is apparent from other observations that the size of the central black hole determines the size of the galaxy nucleus. Thus there must be some connection between the formation of star in the nucleus and the black hole there. I personally think the whole problem arises because presently known star formation processes cannot produce stars in the environment close to the central black hole. However, I tend to believe that processes acting early on to produce stars in the galactic nucleus region were probably different, and certainly in a different environment, to those acting today.

</font><blockquote>quote:</font><hr />The second stellar riddle is posed by something called Complex H – a gas cloud “about 108,000 light-years from the Milky Way’s core, [which] stretches 33,000 light-years across, and contains 6 million suns’ worth of hydrogen gas.” What’s wrong with this?

It’s circling the Milky Way.

In a direction opposite to our galaxy’s rotation.

So what. The Magellanic Clouds also go the wrong way. Is this a problem? No!

from http://www.nrao.edu/pr/2003/complexh/
These results place Complex H in a small club of Galactic satellites whose orbits do not follow the rotation of the rest of the Milky Way. Among the most prominent of these objects are the Magellanic Clouds, which also are being affected by their interaction with the Milky Way, and are shedding their gas in a long stream.
Since large galaxies, like the Milky Way, form by devouring smaller galaxies, clusters of stars, and massive clouds of hydrogen, it is not unusual for objects to be pulled into orbit around the Galaxy from directions other than that of Galactic rotation.
"Astronomers have seen evidence that this accreting material can come in from wild orbits," said Butler Burton, an astronomer with the NRAO in Charlottesville, Virginia. "The Magellanic clouds are being torn apart from their interaction with the Milky Way, and there are globular clusters rotating the wrong way. There is evidence that stuff was going every-which-way at the beginning of the Galaxy, and Complex H is probably left over from that chaotic period." </font>[/QUOTE]The problem is the high velocity with which Complex H is traveling. If it is orbiting at that speed, it should have already passed through the plane of the galaxy and interacted with it, and disrupted, long ago. This may point to a younger age for Complex H than is being considered by these quotes. If so, a re-think of the processes operating in the immediate environment around our galaxy may be needed.

</font><blockquote>quote:</font><hr />
So what we are seeing near the center of our galaxy are stars of high metal content and mass and the astronomers can’t figure how they got there. If the universe is young, however, we do not have a problem with them being there. If these ‘metals’ were formed as part of the creation process instead of being manufactured in stars (as is currently thought), then there is no reason at all why a high metal content should not be found wherever our Creator decided to put it!

There's no problem with the metal content of the stars. The problem is that the stars are too short lived to have an easy explanation for being where they are. </font>[/QUOTE]The metal content also is an age indicator. Metal-poor stars are considered to be much ‘older’ than metal rich stars. If there were a low metal concentration, the issue of how they got near the galaxy’s central black hole so quickly would have been resolved. There would have been time to spiral in to that position, and, in the process, probably grow in size through interaction with other stars (merger or collision in a densely populated environment).

see next post for part II

[ June 28, 2003, 08:55 PM: Message edited by: Helen ]

 

[Helen]

I would like to hear how you explain them being where they are in your chronology. I thought you allowed for stars being formed rather than just created. If they formed, you have the same problems as the astronomers in getting them where they are, you just have less time to do it. 6000 years instead of 10,000,000 years.

On chronology matters, I think you probably mean 10 billion years rather than 10 million. The chronology I am looking at is more than 6000 years, but less than 10,000; probably something close to 8000.

As far as the formation process goes, I do have something in mind. At this stage, no calculations have been done, but the germ of an idea is there. Bear with me while I point out an important problem with planet formation, and then apply a solution to that to the formation of stars.

Part of the puzzle is that protoplanetary disks must form much faster than conventional accretion theory has indicated. On that approach, Jupiter-like planets take as much as 10 million years to form. The problem is that “Direct telescope observations suggest that protoplanetary disks don’t last more than about 7 million years, and studies of the environment in which stars form suggest that many disks may evaporate in much less time.” That quote came from Ron Cowen in Science News, Vol.163, No.4, p.56, January 25, 2003 in an article entitled “Planet formation on the fast track”. Indeed, the article quotes Lucio Mayer of the University of Zurich in Switzerland as saying that young stars “are extremely hot, and the ultraviolet light they blast into space can evaporate a protoplanetary disk in less than 100,000 years.” Yes! That is one hundred thousand years.

This is emphasized by Thomas Quinn of the University of Washington in Seattle who, using the data indicating 100,000 years, stated that “If a gas giant planet can’t form quickly, it probably can’t form at all.” He thus concludes that “If the core-accretion model is correct, gas giants ought to be rare. Yet since 1995, astronomers have found more than 100 extrasolar planets, and most of them are at least as massive as Jupiter.”

One solution that is being offered at the moment is gravitational instability in a disk of swirling gas. This would cause the disk to become unstable and fragment into clumps as big as modest sized planets that would continue to pull in more material according to Alan Boss of the Carnegie Institution of Washington (D.C.). Initial computer modeling suggests that the disk will fragment into massive clumps “in just a few hundred years.”

But this model has problems of its own. Jack Lissauer of NASA’s Ames Research centre in Mountain View California maintains that “in the team’s model, the disk will first undergo a different kind of instability: Material would initially clump but then quickly spread out uniformly, hindering or preventing the large-scale clumping required to make big planets.”

So there is the problem, and a sort of solution. If planet formation can happen quickly by some such process, it is likely that stars can also. Everyone agrees that the whole process starts of with a swirling mass of gas, but the problems come after that. Let’s back off just for a moment and look at things a little differently.

Modern science and the Bible both agree that the heavens were expanded quickly. A study of the Hebrew indicates that the expansion process was completed sometime in the 6 Days of Creation Week. As a result of this expansion process, the material from which the stars and planets formed was in violent turbulent motion. So throughout the cosmos there were a series of whirlpools of various sizes, from giant on down – a whole hierarchy of vortices and eddies as well as quieter areas between vortices. As the cosmos was expanded out, the temperature had to drop. This allowed some elements (which may well have been part of the creation process itself and not the total result of star processes) to solidify in the mix on a dropping temperature sequence. Consequently, the vortices would come to contain solids as well as gases.

What happens in a swirling mixture of fluids and solids? Look at a river. As it swirls around a bend, the solids get concentrated on the inside of the curve. If you have a circular swimming pool that has debris and dirt in it, and the whole mass is set rotating, the debris gets concentrated in the centre. Do an experiment. Get a glass of water, put a small teaspoon of sand in it, stir the mixture in one direction vigorously, pull the spoon out, and watch what happens. As the mixture slows down, the sand becomes concentrated in the centre. It does not take hundreds of years, let alone thousands, but only a few seconds. It is possible that planets and other bodies might be built up quickly by some similar whirlpool/vortex process.

</font><blockquote>quote:</font><hr />
As far as the gas cloud goes, if it is a satellite of our Milky Way and is ‘only’ 108,000 light years away, and if it has been there as long as they think it has, then why hasn’t it been pulled in and disrupted? [snip, read above]

Again, I do not have what you read but I do have an article from the Robert C. Byrd Green Bank Telescope where the study was conducted. There is no indication of any problems to be explained by the observations. In fact, the observations have simplified some of what was thought about Complex H.

Here is the article again. http://www.nrao.edu/pr/2003/complexh/ </font>[/QUOTE]Thanks for the additional information and the link. One of the quotes from the above reads:

High velocity clouds are essentially what their name implies, fast-moving clouds of predominately neutral atomic hydrogen. They are often found at great distances from the disk of the Milky Way, and may be left over material from the formation of our Galaxy and other galaxies in our Local Group. Over time, these objects can become incorporated into larger galaxies, just as small asteroids left over from the formation of the solar system sometimes collide with the Earth.

And this raises a question: if they are so fast moving, and if, in time, they will be absorbed into larger galaxies, why are any of them left in existence after 10 billion years or more?

Then, looking at the drawing, there is something almost amusing. The blue is hydrogen. We don’t know for sure that it is there, but it has been drawn in so that some of the ‘missing mass’ might be accounted for. If that hydrogen cloud does, in fact, exist, the motion of Complex H through this hydrogen would degrade its orbit even more quickly than passing through the plane of our galaxy. It would be continually slowed by the hydrogen and become dispersed within our galaxy even more quickly.

A quote from within the article states, "The Magellanic clouds are being torn apart from their interaction with the Milky Way, and there are globular clusters rotating the wrong way. There is evidence that stuff was going every-which-way at the beginning of the Galaxy, and Complex H is probably left over from that chaotic period." But if the Magellanic Clouds are only just now being disrupted, after 10 billion years (at least) of existence, there still seems to be a problem. The Magellanic Clouds should have started disrupting a very long time ago and Complex H should be well along in its total disruption by now. It is also interesting that there is an admission regarding the turbulent nature of the early universe, but why should it still be causing anomalous phenomena ten billion years (or more) later?

 

[UTEOTW]

It is by both of us, Barry and Helen...Oh, I don’t know. Wishful thinking? Read on if you think more highly of us than that…

Good to hear from you. Hope you enjoyed your vacation. You should know by now that I like and respect you and enjoy our discussions, even if I do not agree with you. Somewhere inside, I even hope your ideas are right. Thanks also for the original post. I learn so much by tracking down such things to get more information. I only wish that I also had the originals from which you were working. But I'm not subscribed.

This is a possibility, however the metal content still marks them, in current secular understanding, as young.

Yeah, the more metal the more recently the stars must have formed. But because of the range of environments from which stars form I would doubt that we can tell a star that formed 10 million years ago from one that formed 100 million years ago or even 1 billion years ago. But that is only a guess, I haven't investigated it. Young is relative. What really marks them as young is their mass.

The possibility that the stars formed in situ appeared to be discounted in the Science News article.

I don't know how strongly the article discounted this possibility. The paper doesn't seem overly keen on the idea but does not dismiss it entirely. To quote: "This hypothesis warrents consideration because the mechanism for violent compression of any cloud passing close to the black hole is innate to the model...A weakness of this hypothesis is the magnitude of the required compression...Furthermore, this scenario is expected to form stars with a common or biased direction for the angular momentum vectors and random apoapse directions, which is contrary to the observations." ( http://xxx.lanl.gov/abs/astro-ph/0306130 ) It later says that the current observations are on only 8 stars and more observations are necessary to determine if there is a pattern to the distribution.

That raises the possibility that the black hole at the centre of our galaxy may have been more massive, and hence much more active, earlier on (rather like the quasars at the frontiers of the cosmos).

What happened to the mass? Black holes, especially supermassive black holes, do not evaporate very quickly.

The metal content also is an age indicator. Metal-poor stars are considered to be much ‘older’ than metal rich stars. If there were a low metal concentration, the issue of how they got near the galaxy’s central black hole so quickly would have been resolved.

Not quite. No matter how metal poor, they are too massive to be old. I think the level of metals is much less important than that in determining the age of a star, though the content does place a strong restriction on when they could have formed. Our sun is a Population I star (metal rich) and it is considered to be about 4.5 billion years old, much older than the few million years for these stars. From what I understand, it is quite difficult to get an age on a single star, at least if it is main sequence. Now if you have a cluster, you can plot the stars on an HR diagram and get the age of the cluster, or at least its oldest members, from stars leaving the main sequence onto one of the branches. But this study is only concerned with 8 stars.

On chronology matters, I think you probably mean 10 billion years rather than 10 million.

No, I really mean 10 million. The stars are massive and short lived enough to put an upper limit of about 10 million years.

[snip good stuff on planet formation]

This is fascinating stuff. We really do not have good model for planet formation and I would guess that there is not a single process in reality. You bring up a good point on the time issue. There are a lot of variables. In general, the more massive the star the more quickly it would collapse. Lower mass stars can take much longer to collapse. So, I would expect that there would be different times periods allowed for planetary formation in various environments. In any case, you have to get the planets formed before the new star fires up enough to drive off the material for building planets. The possibility of rapid collapse solves a lot of the problems and introduces new ones. I think that the NGST (is it now called the James Webb telescope?) will observe in the IR region. The IR region is better for peering through dust. Maybe once it is on orbit (this may not be exactly correct either since I think it will be parked at one of the Lagrange points, though I think those are still considered "orbits") we will get more information from some of the disks and will help sort this out.

Now you propose rapid collapse to generate these stars. As we discussed earlier, this is one of the possibilities in one of the papers, so it is not to be discounted. Though I am not sure what they mean by rapid collapse as far as time scale goes. You would also need the stars to have been around long enough to have evolved on to the main sequence. But in general terms I can see rapid collapse happening.

[snip stuff on whirlpools and such]

Is there some observational predictions that would come from this? If this could be developed and predictions made that could be compared to what we see this could be interesting. Just casually thinking about it I see issues of conservig angular momentum as everything collapses that could be the basis of observational predictions and possible problems. You still need something heavy to be able to collapse and be solid, but we are addressing that in a different thread. With the angular momentum considerations, I see this as being more difficult to explain retrogade motions. In particular, for this discussion, Complex H and the LMC and SMC would have to have formed close to the Milky Way. There just is not enough time to have brough them in from somewhere else. If they formed close to the Milky Way as it rapidly collapsed, one would expect objects so close by to be traveling in the same way. I also suppose that when you say the "heavens expanded quickly" you mean the material expanded into space rather than the expansion of spacetime itself. I say this because you seem to need the expansion to cause the turbulence and I am not sure I see that coming from an expansion of space itself. Carl Gibson, in separate papers says "the primordial plasma was not strongly turbulent before the transition to neutral gas becuase viscous forces were larger than the inertial vortex forces." He also says "The Gibson theory predicts viscous and weak turbulence forces dominate gravitational condensation after the plasma to gas transition." "Weak" turbulence is not "violent" turbulence.

And this raises a question: if they are so fast moving, and if, in time, they will be absorbed into larger galaxies, why are any of them left in existence after 10 billion years or more? ... But if the Magellanic Clouds are only just now being disrupted, after 10 billion years (at least) of existence, there still seems to be a problem. The Magellanic Clouds should have started disrupting a very long time ago and Complex H should be well along in its total disruption by now. It is also interesting that there is an admission regarding the turbulent nature of the early universe, but why should it still be causing anomalous phenomena ten billion years (or more) later?

I am not sure I have a good answer for you. There is a lot of space between the galaxies. I suppose a lot of things could hide out there for a while. I think there are something like 11 known dwarf galaxies gravitationally bound to the the Milky Way and the possibility of more hiding behind our own dust. So the process of assimilating the small galaxies and gas clouds seems to be ongoing. Since the cloud is closer than originally thought, it is also travelling more slowly than originally thought. I missed the part on turbulence in there. It's also the middle of the night.

 

[mdkluge]

I too am puzzled as to why this should cheer YECs. Supposing the strongest possibility--that we conventional cosmologists just can't ever explain those apparently young stars in the neighborhood of the black hole at the center of our galaxy, what then?

Helen mentions that those stars could have been created rather than evolved. Indeed, but what would that have to do with young-earth creationism. They might as well have been created in situ some ten million years ago. Of course that would be contrary to naturalistic cosmology, but it would do nothing to support YEC.