So many stars, so little time
ante...@googlemail.com
fascinating information coming out of this group, but now I've been
hit by an observation that doesn't seem to be covered in the archive,
and which I thought was worth posting so that full justice could be
done to it.
Our universe has galaxies numbering in the order of 100 billion, and
each galaxy contains in the order of 100 billion stars. That gives
around 1x10^22 stars in the galaxy total, and, assuming the age of the
universe to be 14 billion years, that works out to an average of about
23,000 stars forming per second over the whole history of the
universe. Given that there are multiple "generations" of stars and
that star formation can take millions of years, then this figure must
in reality be larger, although over a slightly shorter time-scale.
It's not really the size of the value I've calculated (if correct)
that bothers me- I'm fully aware of the "Appeal to Incredulity"
fallacy and how easy it might be to get caught up in it when dealing
with the scale of the universe- I'm more interested to know if this is
really the consensus: that despite, from our point of view, star
formation is a slow and laborious process that we don't get to see in
a lifetime, in reality tens of thousands of new stars are reaching the
ignition stage across the universe every second?
Additionally, what do you make of the creationist claim that 1x10^22
is too many stars to have formed in 13.7 billion years? Is the rate
of star formation across the universe (high tens of thousands per
second or whatever) fast enough to dispute that claim, or are there
other mechanisms here that I'm missing?
josephus
There is a question that certain globular starts are 13 billion years
old and the age calculate for the universe was 12.5. oops -- so a lot of
people looked at the problem, collected new data, and re established
13.5 billion years as the age of the universe. science is tenative and
you can expect various values to be updated. stars have lifetimes
associated with their mass. the more mass the shorter the life.
all of this science gives creationists gas.
josephus
--
I go sailing in the Summer and
look at STARS in the Winter.
"Everybody is igernant, jist on differt subjects"
Will Rogers Jr.
"it aint what you know that gets you in trouble
it is what you know that aint so"
Josh Billings.
Ralph
<ante...@googlemail.com> wrote in message
news:1190515027....@k79g2000hse.googlegroups.com...
The apparent discrepancy between what likely exists, and what we actually
see as existing, is explained by the fact that we don't see the whole
universe. The farther away objects are, the farther back in time they are.
Or to put it another way - "from our point of view" we never see now, only
how it was, once upon a time. <g>
-ralph
R. Baldwin
An interesting thing to consider is how close together all those stars would
be, if the Universe were 6,000 years old.
Shane
> Hi everyone, I've been content to observe and absorb all of the
> fascinating information coming out of this group, but now I've been
> hit by an observation that doesn't seem to be covered in the archive,
> and which I thought was worth posting so that full justice could be
> done to it.
>
> Our universe has galaxies numbering in the order of 100 billion, and
> each galaxy contains in the order of 100 billion stars. That gives
> around 1x10^22 stars in the galaxy total, and, assuming the age of the
> universe to be 14 billion years, that works out to an average of about
> 23,000 stars forming per second over the whole history of the
> universe. Given that there are multiple "generations" of stars and
> that star formation can take millions of years, then this figure must
> in reality be larger, although over a slightly shorter time-scale.
>
> It's not really the size of the value I've calculated (if correct)
> that bothers me- I'm fully aware of the "Appeal to Incredulity"
> fallacy and how easy it might be to get caught up in it when dealing
> with the scale of the universe- I'm more interested to know if this is
> really the consensus: that despite, from our point of view, star
> formation is a slow and laborious process that we don't get to see in
> a lifetime, in reality tens of thousands of new stars are reaching the
> ignition stage across the universe every second?
Why do you assume that stars are formed at a steady rate? Wouldnt it be
far more logical to assume that star formation in the early stages of
the universe was a much different proposition than now. More material in
a smaller volume would tend, I would guess, to lend itself to very rapid
star formation, and hence high star formation rates.
Why do you assume that star formation is still going on at close to some
original rate?
> Additionally, what do you make of the creationist claim that 1x10^22
> is too many stars to have formed in 13.7 billion years?
The same thing I make of nearly all creationist claims, an assumption,
based on the overwhelming evidence of their preferred methodology, that
they are, either knowingly or ignorantly, talking horse pucky.
> Is the rate
> of star formation across the universe (high tens of thousands per
> second or whatever) fast enough to dispute that claim,
Yes, the stars are here aren't they?
> or are there
> other mechanisms here that I'm missing?
Yes, its called research.
Ernest Major
ante...@googlemail.com writes
>Hi everyone, I've been content to observe and absorb all of the
>fascinating information coming out of this group, but now I've been hit
>by an observation that doesn't seem to be covered in the archive, and
>which I thought was worth posting so that full justice could be done to
>it.
>
>Our universe has galaxies numbering in the order of 100 billion, and
>each galaxy contains in the order of 100 billion stars. That gives
>around 1x10^22 stars in the galaxy total, and, assuming the age of the
>universe to be 14 billion years, that works out to an average of about
>23,000 stars forming per second over the whole history of the universe.
>Given that there are multiple "generations" of stars and that star
>formation can take millions of years, then this figure must in reality
>be larger, although over a slightly shorter time-scale.
>
>It's not really the size of the value I've calculated (if correct) that
>bothers me- I'm fully aware of the "Appeal to Incredulity" fallacy and
>how easy it might be to get caught up in it when dealing with the scale
>of the universe- I'm more interested to know if this is really the
>consensus: that despite, from our point of view, star formation is a
>slow and laborious process that we don't get to see in a lifetime, in
>reality tens of thousands of new stars are reaching the ignition stage
>across the universe every second?
I think that the number you should be interested in is the number
forming close enough for us to see, and not buried deep in a dust cloud,
rather than the number forming over the universe as a whole.
Also, it seems to me that "ignition" is not a process that takes place
in seconds. As a protostar contracts the centre gets hotter and hotter,
and eventually it gets hot enough for pp fusion. Initially the rate is
small, but as the heat increases the rate also increases. The positive
feedback from the heat increases the fusion rate, so the fusion rate
over time follows a sigmoidal(?ish) curve over time, from none, to a
final nearly steady state. My intuition is that this process takes more
than a second.
The extra energy released by the fusion takes time to propagate to the
surface of the star. The sharper the onset of fusion the more,
proportionally, the luminosity increase at the surface is spread out.
>
>Additionally, what do you make of the creationist claim that 1x10^22 is
>too many stars to have formed in 13.7 billion years? Is the rate of
>star formation across the universe (high tens of thousands per second
>or whatever) fast enough to dispute that claim, or are there other
>mechanisms here that I'm missing?
>
Go back to the Milky Way galaxy. You're talking about 10^11 stars
forming in 10^10 years, or ten per annum (on average). (The number in
the process of formation is several orders larger, depending on how long
the process of formation takes. Note also that the rate of formation is
episodic - consider starburst galaxies.)
--
alias Ernest Major
Robert Carnegie
anter...@googlemail.com wrote:
> Hi everyone, I've been content to observe and absorb all of the
> fascinating information coming out of this group, but now I've been
> hit by an observation that doesn't seem to be covered in the archive,
> and which I thought was worth posting so that full justice could be
> done to it.
>
> Our universe has galaxies numbering in the order of 100 billion, and
> each galaxy contains in the order of 100 billion stars. That gives
> around 1x10^22 stars in the galaxy total, and, assuming the age of the
> universe to be 14 billion years, that works out to an average of about
> 23,000 stars forming per second over the whole history of the
> universe. Given that there are multiple "generations" of stars and
> that star formation can take millions of years, then this figure must
> in reality be larger, although over a slightly shorter time-scale.
>
> It's not really the size of the value I've calculated (if correct)
> that bothers me- I'm fully aware of the "Appeal to Incredulity"
> fallacy and how easy it might be to get caught up in it when dealing
> with the scale of the universe- I'm more interested to know if this is
> really the consensus: that despite, from our point of view, star
> formation is a slow and laborious process that we don't get to see in
> a lifetime, in reality tens of thousands of new stars are reaching the
> ignition stage across the universe every second?
It's not unreasonable.
The universe /must/ be larger than what we see. It would not be, if
in the far distance of the universe, you could see the back of your
own head - so to speak. But I'm told this has been tested; that is to
say, distant regions of the universe are not our own region viewed
through a closed circuit of space.
For various reasons I think few astronomers would swear that more than
one star per second is forming in the universe, or fewer than, well,
we can't see the edge.
Your sstars-in-galaxy-in-universe figures are those given at
http://creationwiki.org/Complex_specified_information .
Other religions, and scientists without a particular axe to grind in
the area, have different views; for instance
http://observantastronomer.blogspot.com/2006/03/number-of-stars-in-universe.html
> Additionally, what do you make of the creationist claim that 1x10^22
> is too many stars to have formed in 13.7 billion years? Is the rate
> of star formation across the universe (high tens of thousands per
> second or whatever) fast enough to dispute that claim, or are there
> other mechanisms here that I'm missing?
What would bear is an estimate from observation of the current rate of
star formation. This would be expected to be consistent with the
estimated age of the universe, obviously! This seems to be not seen
as controversial (there was a "missing mass" problem but not a star-
birth problem), and I'm not aware of a creationist claim that 13.7
billion years is not enough time for 10^22 stars to form. You don't
expect them to argue that the universe must be older than scientists
claim! But on the CreationWiki page that I linked, there is a claim
that billions of years and umptillions of stars are not enough for /
proteins/ to form. But it's junk.
How about the number of atoms in any respectable amount of matter -
Avogadro's number. And then how about radioactive decay. In a
typical nuclear fission power plant, how many atoms are split apart in
one second to generate electrical power? Or in an automobile, how
many molecules of hydrocarbon are burnt in one second, and how many
oxygen molecules consumed? Are these incredible numbers?
Steve Wolstenholme
<rja.ca...@excite.com> wrote:
>The universe /must/ be larger than what we see. It would not be, if
>in the far distance of the universe, you could see the back of your
>own head - so to speak. But I'm told this has been tested; that is to
>say, distant regions of the universe are not our own region viewed
>through a closed circuit of space.
Anything traveling at the speed of light coming from any part of the
universe more than the age of the known universe has not reached here
yet.
Steve
--
Stephen Wolstenholme Neural Planner Software Ltd
EasyNN-plus. The easy way to build neural networks.
Harry K
wrote:
> <anter...@googlemail.com> wrote in message
>
> - Show quoted text -
Brings up a mental image.
God: "Let there be light"
God: DO OVER! DO OVER!
ifitmov...@hotmail.com
many people who are smaller believers in creationism than myself, but
this has been the first creationist claim I've read (and there have
been a few!) that made me intrigued rather than made me roll my eyes
immediately- I wanted to know how to respond to it, really.
> Why do you assume that stars are formed at a steady rate? Wouldnt it be
> far more logical to assume that star formation in the early stages of
> the universe was a much different proposition than now. More material in
> a smaller volume would tend, I would guess, to lend itself to very rapid
> star formation, and hence high star formation rates.
> Why do you assume that star formation is still going on at close to some
> original rate?
Well, I didn't necessarily- I pointed out that the numbers implied
that *average* steady rate. But if your response is that in the
hotter, more hydrogen-abundant early stages of the universe, stars
were formed at a fantastic rate compared to how often they form now,
that seems plausible enough.
> > Is the rate
> > of star formation across the universe (high tens of thousands per
> > second or whatever) fast enough to dispute that claim,
>
> Yes, the stars are here aren't they?
Not sure that argument would fly with a creationist with a passing
familiarity with logic- "It has to be true, because if it wasn't, the
current theory would be wrong, and that's impossible!" I'd like to
hit back with science, rather than give more weight to their wrong
claims that a non-God-based origin of all things is still a religion.
> An interesting thing to consider is how close together all those stars would
> be, if the Universe were 6,000 years old.
Now you know they'd just say the Big Bang theory is wrong, and God
could easily have whipped up a huge universe with countless billions
of billions of stars in far less than 6000 years.
> You don't
> expect them to argue that the universe must be older than scientists
> claim!
Of course not, what this guy was trying to do was to claim that even
allowing for the scientists' estimation of the age of the universe
rather than the creationist one, there *still* isn't enough time for
all the stars to have formed, so there's a fatal flaw in there
somewhere, praise Jebus!
Thanks for all the responses so far, people!
VoiceOfReason
wrote:
> <anter...@googlemail.com> wrote in message
Brings a whole new meaning to the words "Big Bang."
R. Baldwin
news:1190563833....@w3g2000hsg.googlegroups.com...
[snip]
>
>> An interesting thing to consider is how close together all those stars
>> would
>> be, if the Universe were 6,000 years old.
>
> Now you know they'd just say the Big Bang theory is wrong, and God
> could easily have whipped up a huge universe with countless billions
> of billions of stars in far less than 6000 years.
>
Try packing the observable stars into a 6000 light-year radius. After all,
we cannot observe light that started farther away than it can travel since
the beginning of time.
ante...@googlemail.com
> <ifitmovesnuk...@hotmail.com> wrote in message
Well the person I was debating this with sprinkled Humphreys' model
onto the proceedings, along with the claimed "Time Dilation" effects.
Shane
You can quote the post you are responding to in Google Groups by
selecting 'more options' (or similar wording) located near the top of
the post and using the reply option there.
Also if you don't want to fall foul of the moderator, you best be very
clear that you and the OP are the same person as is implied below. One
of the few bannable offences here is nym shifting.
> Heh, I'd just like to point out that you'd be hard pressed to find
> many people who are smaller believers in creationism than myself, but
> this has been the first creationist claim I've read (and there have
> been a few!) that made me intrigued rather than made me roll my eyes
> immediately- I wanted to know how to respond to it, really.
>
>> Why do you assume that stars are formed at a steady rate? Wouldnt it be
>> far more logical to assume that star formation in the early stages of
>> the universe was a much different proposition than now. More material in
>> a smaller volume would tend, I would guess, to lend itself to very rapid
>> star formation, and hence high star formation rates.
>> Why do you assume that star formation is still going on at close to some
>> original rate?
>
> Well, I didn't necessarily- I pointed out that the numbers implied
> that *average* steady rate.
And then asked why don't we see that rate today? which *implies* that
you do make such an assumption.
> But if your response is that in the
> hotter, more hydrogen-abundant early stages of the universe, stars
> were formed at a fantastic rate compared to how often they form now,
> that seems plausible enough.
>
>>> Is the rate
>>> of star formation across the universe (high tens of thousands per
>>> second or whatever) fast enough to dispute that claim,
>>
>> Yes, the stars are here aren't they?
>
> Not sure that argument would fly with a creationist with a passing
> familiarity with logic- "It has to be true, because if it wasn't, the
> current theory would be wrong, and that's impossible!"
Please point out where I said or implied that the current theory
cannot be wrong? All I said is that the stars are here, and followiing
on from that, by implication is that they obviously they got here
somehow. So the formation rate of stars is high enogh to account for
the number of stars we have today, no matter what the cause of the
formation is.
> I'd like to
> hit back with science, rather than give more weight to their wrong
> claims that a non-God-based origin of all things is still a religion.
What is stopping you?
<snip stuff in response to someone else>
R. Baldwin
news:1190584145.9...@n39g2000hsh.googlegroups.com...
You might be interested in this:
http://www.reasons.org/resources/apologetics/unravelling.shtml
Robert Carnegie
That is not enough. I handwaved myself that some scientist probably
would have called "foul" or maybe "whoops" if the rate of star
formation by observation and specific theory was inconsistent with the
estimated age of the universe and the numbers of stars now observed -
just as was done with the "missing mass" or "dark matter" in the
universe. But the theory that the stars were all formed over time by
the same consistent natural processes that govern the universe today
must be defended. If there is no theory of star formation that
accounts for the number of stars observed in this galaxy... let's
limit it to this galaxy and let the others look after themselves...
if no theory, then definitely there is a problem with cosmology.
I'm going to post this issue at the "Bad Astronomy / Universe Today"
forums. I expect a quick answer, although, who knows.
At the moment, my layman's understanding includes:
- Current stars with a significant proportion of "metal" are called
"Population I". In star studies, "metal" means any chemical element
nucleus other than hydrogen or helium, the gases that are believed to
have made up nearly all of the normal matter in the universe after the
"Big Bang" and immediately ensuing developments. "Metals" are formed
by natural fusion in stars, but "Population I" stars are believed to
have been formed by gravitation in clouds of gas already containing
those atoms. that is because the atoms were formed during, or at the
end of, the lives of earlier stars - Population II and possibly
Population III - which did end their lives by exploding.
- Larger stars live shorter lives, and vice versa, but smaller gas
masses may never "ignite" as a star.
- It is believed that many stars have come and gone. Some new stars
seem to be forming nowadays. this will continue, but not forever.
- The universe is believed to be around 13.7 billion years old. The
sun is believed to have been "burning" for around 5 billion years, and
to be good for another 5 billion. Stars rather larger than the sun
could have come and gone in the 8.7 (roughly) billion years before the
sun lit up.
ante...@googlemail.com
> On Sun, 23 Sep 2007 09:10:33 -0700, ifitmovesnuk...@hotmail.com wrote:
>
> You can quote the post you are responding to in Google Groups by
> selecting 'more options' (or similar wording) located near the top of
> the post and using the reply option there.
>
> Also if you don't want to fall foul of the moderator, you best be very
> clear that you and the OP are the same person as is implied below. One
> of the few bannable offences here is nym shifting.
>
Thanks for the information, yes, I am the same poster- I signed up for
a Google account with one address, but wanted to post in this
newsgroup with another one, and owing to my unfamiliarity with
newsgroups they seem to have gotten mixed up. I think I've cracked it
though, so please let me know if I do it again. Apologies to the
mods, if you're watching!
>
>
>
> > Well, I didn't necessarily- I pointed out that the numbers implied
> > that *average* steady rate.
>
> And then asked why don't we see that rate today? which *implies* that
> you do make such an assumption.
>
Yes, I got a bit carried away. The essence of that question though
was attempting to find out what the current scientific consensus on
the issue was.
> Please point out where I said or implied that the current theory
> cannot be wrong? All I said is that the stars are here, and followiing
> on from that, by implication is that they obviously they got here
> somehow. So the formation rate of stars is high enogh to account for
> the number of stars we have today, no matter what the cause of the
> formation is.
Sorry, I didn't mean to imply you said that. I was thinking what a
creationist would hear if I gave the same kind of response to them,
because they think stars definitely *don't* form fast enough
naturally, that's the whole point of their argument that I presented
here to be picked apart.
>
> > I'd like to
> > hit back with science, rather than give more weight to their wrong
> > claims that a non-God-based origin of all things is still a religion.
>
> What is stopping you?
>
Lack of knowledge on the subject, which brings us to why I posted here
in the first place. :) The talk.origins archive is brilliant, but it
let me down in this instance.
Don Cates
From: <http://www.ism.ucalgary.ca/top/sf_FAQ.html>
"My 8-year old son is doing a project for a science fair and is trying
to answer the question "How often are stars born?". We have tried to
find a good starting point but have so far come up empty handed. Could
you please steer us in the right directly where we might be able to
find the information he is looking for (and at his level).
Wow! There aren't too many star formation resources that are friendly
to adults, let alone children. So let me try to answer this myself.
To answer this question we need to talk about the number of stars born
each year or, more accurately, the amount of material (gas & dust)
that is converted into stars per year. This is expressed in solar
masses per year (one solar mass is equal to the mass of our Sun =
2x10^27 kg). This quantity is called the "star formation rate". In our
Galaxy the current star formation rate is about 3 solar masses per
year (i.e. interstellar gas and dust corresponding to about 3 times
the mass of the Sun goes into stars each year). However, all this mass
doesn't necessarily go into 1 star. Some stars are more massive than 3
solar masses and some are less massive. However, stars like our Sun (1
solar mass) are quite common and so we can approximate the star
formation rate to be about 3 stars (like our Sun) per year in our
Galaxy.
Astronomers estimate that our Galaxy (the Milky Way) has a total mass
of about 5x10^11 solar masses (500 billion times the mass of the Sun!)
and contains about 200 billion stars (most of which are similar to the
Sun). Futhermore, we estimate that there are about 50 billion galaxies
in the entire observable Universe. Now all galaxies are different -
our own is a typical spiral galaxy, but there are large and small
spirals, giant and dwarf ellipticals, irregulars, etc. However, if we
once again assume that our own Milky Way Galaxy represents an average
type of galaxy, we can calculate that there are roughly 150 billion
stars born per year in the entire Universe. This corresponds to about
400 million stars born per day or 4800 stars per second! If we turn
this around to answer your son's question directly, this mean that
throughout the entire Universe, a star is born every 0.0002 seconds
(i.e. every 2, 10,000th's of a second)!! "
Remember, "Space is big. Really big. You just won't believe how vastly
hugely mindbogglingly big it is. I mean you may think it’s a long way
down the road to the chemist, but that’s just peanuts to space."
--
Don Cates ("he's a cunning rascal" - PN)
Don Cates
On Mon, 24 Sep 2007 01:54:01 -0000, ante...@googlemail.com posted:
>On 24 Sep, 00:00, Shane <remarcsdNOS...@ozemail.com.au> wrote:
And this is an estimate of present the rate, Evidence indicates it was
much higher in the past.
Shane
> On 24 Sep, 00:00, Shane <remarcsdNOS...@ozemail.com.au> wrote:
>> On Sun, 23 Sep 2007 09:10:33 -0700, ifitmovesnuk...@hotmail.com wrote:
>>
>> You can quote the post you are responding to in Google Groups by
>> selecting 'more options' (or similar wording) located near the top of
>> the post and using the reply option there.
>>
>> Also if you don't want to fall foul of the moderator, you best be very
>> clear that you and the OP are the same person as is implied below. One
>> of the few bannable offences here is nym shifting.
>>
>
> Thanks for the information, yes, I am the same poster- I signed up for
> a Google account with one address, but wanted to post in this
> newsgroup with another one, and owing to my unfamiliarity with
> newsgroups they seem to have gotten mixed up. I think I've cracked it
> though, so please let me know if I do it again. Apologies to the
> mods, if you're watching!
There is only one of them, David Iain Greig, (DIG) and you are
unlikely to have come to his attention so soon.
>>> Well, I didn't necessarily- I pointed out that the numbers implied
>>> that *average* steady rate.
>>
>> And then asked why don't we see that rate today? which *implies* that
>> you do make such an assumption.
>>
>
> Yes, I got a bit carried away. The essence of that question though
> was attempting to find out what the current scientific consensus on
> the issue was.
>
>> Please point out where I said or implied that the current theory
>> cannot be wrong? All I said is that the stars are here, and followiing
>> on from that, by implication is that they obviously they got here
>> somehow. So the formation rate of stars is high enogh to account for
>> the number of stars we have today, no matter what the cause of the
>> formation is.
>
> Sorry, I didn't mean to imply you said that.
I also apologise for being grouchy, it seems I have misread your
intent and responded poorly.
> I was thinking what a
> creationist would hear if I gave the same kind of response to them,
> because they think stars definitely *don't* form fast enough
> naturally, that's the whole point of their argument that I presented
> here to be picked apart.
No biggie. The reason I responded as I did, is that I feel no
particular compulsion to fulfill the creationist expectation that
science has a definitive answer to everything, and if it doesn't then
the only answer left is that goddidit. *We don't know* is a perfectly
rational answer to some questions.
>>> I'd like to
>>> hit back with science, rather than give more weight to their wrong
>>> claims that a non-God-based origin of all things is still a religion.
>>
>> What is stopping you?
>>
>
> Lack of knowledge on the subject, which brings us to why I posted here
> in the first place. :) The talk.origins archive is brilliant, but it
> let me down in this instance.
T.O. is more focused on biological origins rather than cosmic origins,
and as you have found, and others are pointing out, there is not a lot
of info available. Robert Carnegie's response to my previous post is
probably worth reading if you have not already done so. He is asking
the question in another forum, and may get some more up to date
answers.
josephus
take a look at the HR diagram it is also a probability plot for size I
think there is some data on numbers of STARS at any mass. it is
important to people studying them. but remember the sequence OBAFGKMRN
(Oh Be A Fine Girl Kiss Me Right Now) O are the most massive and
hottest stars. I forget the ratios but a rule of thumb is each group is
1/2 as prevalent as the next one. the greatest mass of stars are the N
groups of cool dim stars. the search for DARK MATTER caused people to
look for low mass cool stars. Brown Dwarfs.
G -- our Sun is a G2 and it is smack in the middle of the HR Diagram.
HR is a serious scientific diagram and shows many facts about stars.
including the AGES of stars. and check out Menzel "The Golden Book of
Astronomy" 1976 or so and look at the older astronomical handbook
"19XX Yearbook of Astronomy" by Patrick Moore. both of these are
suitable to Amature Astronomers that are NON TECHNICAL. most of the
amatures are "observers" and not technical at all. I have in my
possession the "Astronomical Handbook or DATA" it was published
sometime in the 1980's I have a copy but I cant find it right now.
as a thought checkout the Introductory Astronomy book at your near by
college.
Iain
>So many stars, so little time
A little nonsense now and then, is relished by the wisest men....
~Iain
Robert Carnegie
Don Cates wrote:
> From: <http://www.ism.ucalgary.ca/top/sf_FAQ.html>
> To answer this question we need to talk about the number of stars born
> each year or, more accurately, the amount of material (gas & dust)
> that is converted into stars per year. This is expressed in solar
> masses per year (one solar mass is equal to the mass of our Sun =
> 2x10^27 kg). This quantity is called the "star formation rate". In our
> Galaxy the current star formation rate is about 3 solar masses per
> year (i.e. interstellar gas and dust corresponding to about 3 times
> the mass of the Sun goes into stars each year). However, all this mass
> doesn't necessarily go into 1 star. Some stars are more massive than 3
> solar masses and some are less massive. However, stars like our Sun (1
> solar mass) are quite common and so we can approximate the star
> formation rate to be about 3 stars (like our Sun) per year in our
> Galaxy.
> And this [scaled up to the universe] is an
> estimate of the present rate, Evidence
> indicates it was much higher in the past.
It'd need to be; that only gives around 40 billion stars in 13.7
billion years, and the suspiciously round estimates of stars in this
galaxy seem to be higher than that.
I think this still needs a bit more rigour.
Robert Carnegie
> I'm going to post this issue at the "Bad Astronomy / Universe Today"
> forums.
One guy in particular offered some really good answers.
http://www.bautforum.com/questions-answers/65104-creationism-rate-star-formation-question.html#post1077036
http://www.bautforum.com/questions-answers/65104-creationism-rate-star-formation-question-2.html#post1079444
"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."
That should do it.