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Old 24-September-2007, 01:26 AM
Robert Carnegie Robert Carnegie is offline
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Default Creationism and a "rate of star formation" question

A correspondent (in Usenet talk.origins) is debating a creationist who seems to have posed a rather unusual question (but it may be very familiar?) "1x10^22 [in the universe, estimated] is too many stars to have formed in 13.7 billion years."

This probably does not mean anything - apparently it was offered wrapped in Humphrey "cosmology" - but I think it must be interpreted as "The orthodox theory and rate of formation of stars is not sufficient for the number of stars now seen in the universe, therefore science has got it wrong and in fact God did it."

I presume that if theory really wasn't up to the job of accounting for the stars in the sky then there would be more talk about it - 'dark matter" in its first theoretical incarnation represents a similar cosmological "problem" and it remains a live question - but I am asking in order to make sure.

I also presume that to consider the history of this our own galaxy will be sufficient. Apart from corporate acquisitions, which are common, there is little intercourse between the galaxies.

I am very very much a layman, I don't even look out of the window at night, but it's my understanding that massive stars in the early universe (Populatiion II, III) formed, burned, changed cycle and were liable to explode in the end, seeding the hydrogen/helium gas between stars with "metals" (any element not beginning with H, and the ones that do that I've forgotten), which then appeared in the Population I stars as well as the planet Earth. Smaller early stars lasted for longer, some until now. Smaller bodies still never lit themselves up like proper stars, because there wasn't enough pressure to cause fusion.

And, as stars use up hydrogen, they will leave less around to make new stars. It's like that mathematical puzzle where you make cigarettes out of the butt-ends of used cigarettes, then you smoke the butt-ends of those, and finally you give up and buy nicotine patches.

So, present-day star formation rate may be less than in the old days, and conversely over time it needs to account for stars that no longer exist as well as those that do.

Other interpretations of the original question include that a sign is reversed and 13.7 billion years would produce many -more- stars than we find now, therefore the universe is not as old as that, after all; or a highly garbled version of the argument here,
http://creationwiki.org/Complex_specified_information
- that 13.7 billion years and 10^22 stars are not enough to produce living things by "random chance". The last is nonsense, but numbers one and two are astronomy.

So - are stars known to be born quickly enough to account for the ones that we see? Remember not to beg the question. Thank you!
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Old 24-September-2007, 10:43 PM
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A creationist... seems to have posed a rather unusual question... "10^22... is too many stars to have formed in 13.7 billion years."
That's not a question; it's an assertion. On what does this creationist base this assertion?

Around here, people who make assertions have the burden of providing the observational or at least the theoretical/mathematical/logical support for their assertions, not the other way around. It is not up to serious scientists to go to the trouble of proving baseless assertions wrong!

Besides, this sounds SOOOO typical of creationist arguments, especially those associated with evolution -- the old "argument from incredulity." That is, "I can't imagine how this could be, therefore it can't be!" Things are typically just a lot more complicated than creationists seem to be able to comprehend.

In my experience with such discussions and arguments, I have found that it is simply not worth the time spent trying to educate creationists. It's a very unfortunate situation!

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I presume that if theory really wasn't up to the job of accounting for the stars in the sky then there would be more talk about it.
"How many stars are there?" is not even a very meaningful question. As you say, stars are being born and other stars are "dying" all the time. And why just talk about stars? Stars are just temporary actors on hundreds of billions of galactic stages.
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Old 25-September-2007, 01:26 AM
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There's anecdotal evidence that lay creationists - that's to say, believers rather than preachers (I think) - are confirmed in their beliefs by scientific-sounding arguments from their pastors, and are liable to revise their opinions when the pastor is caught out in error. It may take more than one go... For instance, in a rather futile inquiry for sincere bible-believing actual flat-earthers (I suspect they are all dead, some of them quite recently, ounless someone demonstrates otherwise, also establishing that the person in question is technically sane) someone in t.o claimed to have seen on TV an ex-Amish believer explaining that he quit the church (but joined another very similar one) when an elder insisted on that strange fallacy as biblical truth. But that may not have been recent. Wikipedia says that the last (other) flat-earth church in the U.S. broke up in the 1940s for unrelated reasons.

Back to star formation, someone else in t.o found an attempt at a professional answer at http://www.ism.ucalgary.ca/top/sf_FAQ.html Unfortunately or fortunately for the point I'm trying to make, Dr Rene Plume (trying to help an eight-year-old's school project) estimates that the galaxy contains 200 billion stars (estimates elsewhere vary a lot, I suppose the dim ones are harder to find), with new stars forming at a rate of 3 a year. The calculation that he does not perform implies that the galaxy is at least 66 billion years old. In the latest quotable figure, 13.7 billion years would give us around 40 billion stars in this galaxy. Now that isn't exactly the question that Dr Plume was trying to answer, and it is very simple to say that the rate of star formation was higher in the past and is tailing off. But I think this ought to be shown worked out without - as I say - begging the question; without choosing the figure that the age of the universe requires.

On the face of it, I can simply drop Dr Plume a line and ask him to clarify his remarks, but if someone else here does want to have a go - ? Thanks again.
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Old 25-September-2007, 01:27 AM
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He probably read somewhere that someone made some reasonable sounding assumptions in a model and only got 10^21 stars instead of 10^22. That's a problem for someone looking for a model that really works, but it hardly puts into doubt the whole paradigm. The assumptions are reexamined, and a new model results, it's all a natural part of science. If some radically different solution was in fact correct, there's no reason mainstream models should even be in the right ballpark. Why not 10^10 stars from the predictions, or 10^30? Pseudoscientists are forever asking the wrong questions.
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Old 25-September-2007, 07:00 AM
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Cougar makes a good point. I have witnessed this before. No amount of common sense and science converts the dogmatic creationist.
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Old 25-September-2007, 09:41 AM
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Not wanting to derail this topic, Trojan horse style..., but I do have a fitting tale of this subject matter.
While visiting friends a couple of young fallows were attempting to inform us of the error of science in that the age of the universe was only 5000 years. Oh boy I could not resist jumping in to this conversation with.
" If we can see a galaxy that is many thousands of light years away and we know the speed of light. We can calculate the distance to be some what greater than 5000 light years. But if it did not exist then how do we see it now?" They never did come back.
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Old 25-September-2007, 10:10 AM
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The more I think about this question, the more my brain hurts. I mean how do you even guess what the star creation rate should be. Sooooooooo Sooooooooo many variables.

Then you have to guess how many other galaxies have been hoovered up by the Milky Way. I am not saying this because of the creationist over tones. If I saw any serious attempt to predict star creation activity in the galaxy over it's history, I would just as concerned
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Old 25-September-2007, 10:10 AM
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Well either Vishnu made the universe so it is or appears to be over 13 billion years old or she didn't. If she did make it so it is or appears to be over 13 billion years old we then would expect our observations of the universe to agree with that. If she didn't make the world appear to be over 13 billion years old then our observations wouldn't lead us to think that it is. So when a creationist insists that the universe can't possibly be as old as it appears, they are saying either of two things:

1. Vishnu is incompetent and made a lousy job of making the universe look old.

2. Vishnu is deceptive.

Last edited by Ronald Brak; 25-September-2007 at 11:30 AM..
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Old 25-September-2007, 10:51 AM
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Hmmm... I will need to think about that some more.

Its reasonable science to sagest that star formation will eb. As the amount of fuel available for star formation is depleted by conversion in the stellar masses. I can not imagine a carbon star. I sagest a search in 'wickie' might please you.
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Old 25-September-2007, 12:02 PM
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" If we can see a galaxy that is many thousands of light years away and we know the speed of light. We can calculate the distance to be some what greater than 5000 light years. But if it did not exist then how do we see it now?" They never did come back.
I am surprised they did not come back with the "Doctrine of Apparent Age" or "Mature Creation" with reference in the scriptures that God mad it this way to counter any accusations of deception. That I understand from Creationism Central is the way to deal with evidence which seems to give dates beyond 6000 years.

I did have a further thought on this issue, but as it is nothing to do with stellar formation rates, I can not say anything further.
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Old 25-September-2007, 12:08 PM
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Default Re: Creationism and a "rate of star formation" question

The creationist use of the term "common sense" is a giveaway. That "sense" has led to many major debacles, such as creationism.

The proper term is "good sense", which is much rarer, and usually limited to the realm of freethinkers, rationalists, and the various disciplines of science.
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Old 25-September-2007, 01:20 PM
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Well either Vishnu made the universe so it is or appears to be over 13 billion years old or she didn't. If she did make it so it is or appears to be over 13 billion years old we then would expect our observations of the universe to agree with that. If she didn't make the world appear to be over 13 billion years old then our observations wouldn't lead us to think that it is. So when a creationist insists that the universe can't possibly be as old as it appears, they are saying either of two things:

1. Vishnu is incompetent and made a lousy job of making the universe look old.

2. Vishnu is deceptive.
Brahma creates! Vishnu preserves. Shiva destroys.


Good point Ronald Brak. If we did opt for creationism then who's imaginary friend would we decide is best?

I suggest the Pastafarian sect
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Old 25-September-2007, 01:23 PM
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Then you have to guess how many other galaxies have been hoovered up by the Milky Way.
What a great phrase! Phooey on assimilisation of smaller galaxies. Let's just call it hoovering.
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Old 25-September-2007, 01:28 PM
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I am surprised they did not come back with the "Doctrine of Apparent Age" or "Mature Creation" with reference in the scriptures that God mad it this way to counter any accusations of deception. That I understand from Creationism Central is the way to deal with evidence which seems to give dates beyond 6000 years.
"Doctrine of Apparent Age" was created by some earnestly believing 19th Century European geologists in order to reconcile the "6000 years age" (which they accepted as a given) with their own research that demonstrated otherwise. For some reason "Doctrine of Apparent Age" never really took in US.
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Old 25-September-2007, 02:38 PM
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Originally Posted by Robert Carnegie View Post
This probably does not mean anything - apparently it was offered wrapped in Humphrey "cosmology" - but I think it must be interpreted as "The orthodox theory and rate of formation of stars is not sufficient for the number of stars now seen in the universe, therefore science has got it wrong and in fact God did it."
If this is an older Humphrey issue where Dark Matter was not mainstream, then there should be some merit to the argument of too many stars, perhaps. Today, it is closer to the analogy of Creationists throwing rocks at tanks, except most do not take the time to see the tank for what it is.

Quote:
I presume that if theory really wasn't up to the job of accounting for the stars in the sky then there would be more talk about it - 'dark matter" in its first theoretical incarnation represents a similar cosmological "problem" and it remains a live question - but I am asking in order to make sure.
Dark Matter is likely the explanation for the stellar numbers we observe after only 13.7 billion years post bang.

Quote:
And, as stars use up hydrogen, they will leave less around to make new stars. It's like that mathematical puzzle where you make cigarettes out of the butt-ends of used cigarettes, then you smoke the butt-ends of those, and finally you give up and buy nicotine patches.
I think we would now be in the late 1940's using this analogy. Our stars are still smokin' !!

Quote:
So, present-day star formation rate may be less than in the old days, and conversely over time it needs to account for stars that no longer exist as well as those that do.
I think this is correct.

Quote:
Other interpretations of the original question include that a sign is reversed and 13.7 billion years would produce many -more- stars than we find now, therefore the universe is not as old as that, after all; or a highly garbled version of the argument here,
http://creationwiki.org/Complex_specified_information
- that 13.7 billion years and 10^22 stars are not enough to produce living things by "random chance". The last is nonsense, but numbers one and two are astronomy.
It does not address the "too many" issue. Their logic is interesting but, as Don Meredith used to say, "if if and buts were candy and nuts, we'd all have a Merry Christmas."

[Yet, I am but a mere volunteer heliochromologist (don't ask ), so I count on others to address the Dark Matter aspect more fully.]
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Old 25-September-2007, 03:02 PM
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I'm sorry can't address the exact claims you are talking about (I haven't heard them before). That in mind...

I can't find any good press articles about it, but astronomers have observed star formation to be greater in the past. Looking at galaxies at high redshift (and thus large distance, and thus long ago), we do actually see a significant increase in the rate of star formation amongst early galaxies. This is one of the big discoveries of the Hubble Space Telescope, and the Hubble Deep Field, as well as more recent observations by the Spitzer Space Telescope.

Also, galaxy interactions are one of the main drivers of star formation. And in the early universe, galaxies were a lot closer together, and thus interacted a lot more. We've observed galaxies that are forming hundreds of stars per year, during mergers.
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Old 25-September-2007, 04:12 PM
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Default So many variables . . .

Hmm, what appears to be dark matter has been observed separated from visible galaxies. What happens if a visible galaxy rips through a galaxy-size non-comoving cloud of dark matter? Does the DM trigger star formation in the visible galaxy? Is it disrupted?
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Old 25-September-2007, 11:58 PM
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Lightbulb Pish Tosh

Pish-tosh. 1012 galaxies x 1010 years x 1 solar mass per year = 1022 solar masses of star formation. And since the sun is way more massive than the median star, that's a lot more than 1022 stars. So, do creationists know anything about "back of the envelope arithmetic"? No doubt I have not presented a detailed physical model of star formation, but I can say that 1 solar mass per year is typical of a very low star formation rate. Starburst galaxies can do 10 or even 100 solar masses per year. Surely there are at least 1012 galaxies in the universe (you can get that just by extrapolating deep survey counts to the whole sky), and 1010 years leaves a few billion years of slop for time (13.7 billion is 1010.13672 for all you logarithm freaks). So 1022 stars in 13.7 billion years is, as they say, a piece of cake.
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Old 26-September-2007, 04:31 AM
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Nice, Tim. That's an excellent way to do it!
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Old 26-September-2007, 06:39 AM
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Lightbulb Cosmic star formation rate

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So, present-day star formation rate may be less than in the old days, and conversely over time it needs to account for stars that no longer exist as well as those that do.
The star formation rate of a galaxy can be inferred from its ultraviolet (Lyman-alpha) brightness, which is redshifted into the infrared as we see it. Dust is created by stars, so it's a pretty good indicator too. The cosmic star formation history (from the Max Planck Institute for Astrophysics) shows that the cosmic star formation rate peaked around redshift 5. But that was in 2001, and more recent research would put the peak about redshift 3 (10.4 billion years ago). There is a lot of science out there on the cosmic star formation rate (i.e., Tresse, et al., 2007; Bell, et al., 2005). The star formation rate now is about 1% of what is was 10 billion years ago.

Also note that the sun is quite a bit more massive than the median star. Most of the stars that have been created are still here, because they are not massive enough to have evolved into supernovae or white dwarfs in a universe only about 14 billion years old (a minimal mass red dwarf star will stay on the main sequence for about 100 trillion, or 1014 years).
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Old 26-September-2007, 12:43 PM
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The impression I have is that the individual Creationist was questioning the "how" more than the "what"; how is it that the number of stars have formed, regardless of rates, during the 13.7 billion time frame? Without dark matter, I assume it would have been a good question. Is this correct?
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Old 26-September-2007, 01:50 PM
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Correct, but the OP sounded like it was saying something different. Creationists would have a little problem making the case: "hey, your model requires the existence of something we have not yet found a way to reproducibly observe (dark matter), so it must be wrong". Oops...
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Old 26-September-2007, 01:53 PM
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Hi Tim (end of your 01:39 post) I have not heard that long before: Should that possibly be 100 billion years = 10^11 years? Neil
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Old 26-September-2007, 04:57 PM
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Lightbulb 100 Trillion Years

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Hi Tim (end of your 01:39 post) I have not heard that long before: Should that possibly be 100 billion years = 10^11 years? Neil
No, 1014 years is correct. Fred Adams & Greg Laughlin only allow for "trillions" of years (remember that "trillion" in the USA and "trillion" in the UK don't mean the same number) in their book The Five Ages of the Universe (Touchstone Books, 1999). They also wrote a popular article on the same topic for Sky & Telescope, in the August 1998 issue: "The Future of the Universe". The number I use, 100 trillion years, is the main sequence lifetime for a minimal red dwarf, about 0.08 solar masses, and comes from their earlier technical paper: A dying universe: the long-term fate and evolution of astrophysical objects, Reviews of Modern Physics 69(2): 337-372, April 1997. And that paper was partly motivated by an even earlier paper by Freeman Dyson: Time without end: Physics and biology in an open universe, Reviews of Modern Physics 51(3): 447-460, July 1979 (this one is not available online without a subscription). The long term fate of the universe is far more long term than most people think, although Adams, Laughlin & Dyson all wrote well before dark energy & an accelerated expansion were realized.

Their more recent papers on this topic are: M dwarfs: planet formation and long term evolution, Adams, Bodenheimer & Laughlin, Astronomische Nachrichten 326(10): 913-919, December 2005; Red Dwarfs and the End of the Main Sequence, Adams, Graves & Laughlin, Revista Mexicana de Astronomía y Astrofísica (Serie de Conferencias) 22: 46-49, December 2004. I was able to download the PDF for both without a subscription.
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Old 26-September-2007, 05:16 PM
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Lightbulb Dark matter & star formation

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The impression I have is that the individual Creationist was questioning the "how" more than the "what"; how is it that the number of stars have formed, regardless of rates, during the 13.7 billion time frame? Without dark matter, I assume it would have been a good question. Is this correct?
I don't think dark matter plays much of a role in the small scale process, where stars are actually formed in compressed clouds. However, it certainly is relevant in establishing the gravitational potential, which in turn establishes the large scale structure, which in turn allows for the formation of critical density clouds that can collapse to form stars. There is far more literature on the topic than anyone can cover in a discussion like this, and that makes it an ideal target for creationists. It's easy to make a one paragraph assertion that takes 100 pages of real work to convincingly refute. Springel & Hernquist, 2003 is a good place to start. They show that cosmic star formation rates & densities derived from numerical models in a cold dark matter universe with cosmological constant are in agreement with observational determinations of the same quantities. Anyone who is so inclined can download the pre-print, and follow the 155 citations (so far) to track down even more. Also worth a look: Nagamine, et al., 2001 & Nagamine, Cen & Ostriker, 2000.
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Old 26-September-2007, 05:34 PM
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And that paper was partly motivated by an even earlier paper by Freeman Dyson: Time without end: Physics and biology in an open universe, Reviews of Modern Physics 51(3): 447-460, July 1979 (this one is not available online without a subscription).
Unless you go here;
http://www.aleph.se/Trans/Global/Omega/dyson.txt
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Old 26-September-2007, 05:52 PM
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Oh dear; reading the papers by Adams and Laughlin I see that small red dwarfs will swell up and brighten until they are sun-like in size and luminosity in about a trillion years; the galaxy at that distant time will be full of apparently sun-like stars (and a lot of black dwarfs, but we'll forget about them).

I would be really optimistic about this prospect except for the accelerating expansion of the universe. If the universe is torn apart by a big Rip in less than a trillion years, then this distant time of sun-like red dwarfs will never arrive.
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Old 29-September-2007, 02:39 PM
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Originally Posted by Tim Thompson View Post
There is a lot of science out there on the cosmic star formation rate (i.e., Tresse, et al., 2007; Bell, et al., 2005). The star formation rate now is about 1% of what is was 10 billion years ago.
Cool! Can I bookmark this thread and that post, to show to people? it's just the sort of answer I wanted to get on this; facts, and references. I still haven't seen, say, an estimate of stars in the galaxy or in the universe at different dates, based on observation and theory - perhaps buried in one of the articles you pointed to - but clearly there is, as I expected and hoped, plenty of well-attested star formation to account for the present state of the world. I'd have accepted an "Actually, no one really understands that well, how stars form" but I'd've been disappointed. Science 1, Ignorance 0. So, thank you very much!
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Old 29-September-2007, 08:10 PM
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You might also like to know how the number of galaxies in the visible universe of ~ 130 billion were estimated.

It was discussed in several threads including this one. The Hublle Ultra Deep Field (HUDF) found ~ 10,000 galaxies in an area of sky about 202 x 202 arcseconds, I think. Extrapolating across the entire sky produces the value of 131 billion glaxies.

Hubble also took a similar long exposure image in the southern hemisphere and found a similiar count.
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Old 29-September-2007, 10:03 PM
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What is the rule about discussing creationism? My understanding is that it can lead one to be skating on thin ice re the rules. I had a thought about this subject, but have not voiced it anywhere yet, I do not want to say any more in case I am in violation of forum rules

If I have infracted the rules by asking this, I do apologise and will remove this post if required
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