Astrophysics, schmastrophysics

| 160 Comments

Remember the “we’re-creationists-and-proud-of-it” creationists? Well, despite the press that ID has been getting, the older sort are still around. Today, they’re discussing not the beginning of the universe, but the end. Evidently they don’t like “dark matter” and “dark energy”, explanations that astrophysicists have proposed to explain certain puzzling phenomenon like the fact that galaxies spin faster than the gravity from their observed stars seems to allow.

Now, I think it is perfectly reasonable to criticize these explanations on their merits – it is conceivable, for example, that dark matter doesn’t exist and that instead we need some new physics to describe gravity at the very coarse scale – see for example the latest on MOND (Modified Newtonian Dynamics) in New Scientist (plain text). And the answer to this question could impact our view of the eventual fate of the Universe – i.e., will we get a “Big Crunch” or not?

But I think the creationist solution to the problem leaves something to be desired:

Evolutionists accuse creationists of inventing a “God of the Gaps” to cover for their ignorance of true science. It would appear that the high priests of astrophysics have their own Gods of the Gaps, namely dark matter and dark energy. What will happen to the universe? It won’t be the Big Crunch or the Big Chill, but the Big Furnace: “But the day of the Lord will come like a thief, in which the heavens will pass away with a roar and the elements will be destroyed with intense heat, and the earth and its works will be burned up. Since all these things are to be destroyed in this way, what sort of people ought you to be in holy conduct and godliness, looking for and hastening the coming of the day of God, because of which the heavens will be destroyed by burning, and the elements will melt with intense heat! But according to His promise we are looking for new heavens and a new earth, in which righteousness dwells” (2 Peter 3:10-13).

Astrophysics, schmastrophysics!

160 Comments

I do agree in part that dark matter and dark energy might not be a satisfactory explanation of some astronomical phenomena, but “the Big Furnace”? You gotta be kidding me.

Once again, this only reflects how America’s education fails to give its children a proper understanding of science. Look what happens when you get your science from preachers.

Evolutionists accuse creationists of inventing a “God of the Gaps” to cover for their ignorance of true science. It would appear that the high priests of astrophysics have their own Gods of the Gaps, namely dark matter and dark energy.

Whoever wrote that doesn’t know what ‘god of the gaps’ means.

Evolutionists accuse creationists of inventing a “God of the Gaps” to cover for their ignorance of true science. It would appear that the high priests of astrophysics have their own Gods of the Gaps, namely dark matter and dark energy.

The difference being, of course, that astrophysicists don’t just claim dark matter. They take the next step and say, “If dark matter is the correct explanation, we should expect to observe X, and we should not observe Y.”

Then they try to actually observe X and Y. When they find X but not Y, that’s evidence in support of dark matter.

steve s wrote:

Evolutionists accuse creationists of inventing a “God of the Gaps” to cover for their ignorance of true science. It would appear that the high priests of astrophysics have their own Gods of the Gaps, namely dark matter and dark energy.

Whoever wrote that doesn’t know what ‘god of the gaps’ means.

Right, that should be a “dark matter of the gaps” or “naturalism of the gaps” or “theory with gaps.”

I blame David Heddle. If he’d have properly fine-tuned his puddle, we’d all be so much happier…

…But according to His promise we are looking for new heavens and a new earth, in which righteousness dwells.

Ah, the “oscillating universe” theory: a “big crunch” (which will, of course, involve a lot of heat) leading to – and providing the raw material for – the next “big bang” – and a whole new universe! I can live widdat. Have the YEC’s got a timetable?

it is conceivable, for example, that dark matter doesn’t exist

Well, we know dark matter exists, we’re made of it, and the planet we’re standing on is also made of it. We also detect particles of dark matter all the time. The real dark matter question is what type and quantity of dark matter is needed to explain our observations? I know it’s a pedantic point, but it seems that most people don’t realize that dark matter really means matter that doesn’t emit light, like rocks, or planets, or neutrinos. It doesn’t necessarily mean weird stuff we’ve never seen before. (unless you want to throw black holes into the weird stuff category)

Jacob Bekenstein obviously doesn’t know anything about getting a new theory like MOND accepted by the scientific community. He should have gone to school boards and demanded that MOND be taught in grade school and high school classrooms. Why wasn’t he screaming about critically examining gravitational theory? Where were the politicians crowing about teaching alternate explanations to dark matter?

I just don’t get it.

Have the YEC’s got a timetable?

yes!

the inferno will happen on 6/6/(0)6!

oh… wait..

Equating “gaps” with “god of the gaps” is like equating “closet” with “monster in my closet.”

Science is a work in progress and many theories have gaps. In science, you attempt to fill in the gaps with reasonable explanations. In a “god of the gaps” theology, any gaps are presumed unfillable, and taken as proof of some supernatural explanation. Historically, the gaps have eventually been filled, turning this into a process of steady retrenchment into ever more minor objections.

That’s a surprisingly infomative site with an interesting compilation of science articles… as long as you ignore the “signing statements” that tell you what the article =really= means (handily color-coded for your convenience in not reading).

This from AIG a few days ago:

http://www.answersingenesis.org/hom[…]006/0602.asp

I always thought that distant starlight was a problem for YEC’s but apparently not.

the inferno will happen on 6/6/(0)6!

That’s over. What will the six-crazed maniacs do now?

Probably the same as they did after 6/6/66 !

That’s over. What will the six-crazed maniacs do now?

obviously, they’ll pass the delusion on to their kids and grandkids, and get them all worked up about the end of the world coming on 6/6/6.… in a hundred years.

I always thought that distant starlight was a problem for YEC’s but apparently not.

Wow. On a lark I actually went to that page and followed a couple of links.

My head hurts.

Apparently, Dembski feels that when God dictated Genesis, He was trying to convey the story by speaking to Moses not in metaphors, but in a observationally referenced discription of relatavistically adjusted space/time - clearly a good framework for a talk with a bronze age shepherd

(In fairness, I wasn’t smart enough to follow most of the details. It had something to do with being unable to ever synchronize two clocks - I have a degree in engineering, and have actually seen relativistic time dialtion in ultraprecise reference clocks - and he still lost me. I must be stupid)

Anyway, all these years I though God was trying to say “Yes, Yes, I made the world. Whatever. Now pay attention, here’s the stuff that’s important now. Apparently I was wrong.

From the “analysis” from the AiG post that Peter Henderson’s post #104489:

“Big bang supporters themselves acknowledge that the big bang could not have produced anything heavier than lithium, so the only way to explain the heavier elements, like carbon, is to say that the stars did it. Notice there is no observational evidence or recorded eyewitness accounts to support this, just man’s fallible opinions about the past.”

For some reason spectra from ionized elements from stars that we’ve seen explode don’t constitute “observational evidence”.

It’s interesting that there are repeated references to “man’s fallible opinions about the past”. Apparently man’s opinions (supported by observation, mathematics, and reason) are “fallible” when they involve any thing over 6000 years old. But when man’s opinions about any thing which happened 6000 years ago or less are supported by devine revelation (and contradicted by observation, mathematics, and reason), they are completely infallible.

Sigh…

tonylon: That is “warm dark matter”. It is reasonably clear to astronomers that there is insufficient warm dark matter to explain the rotation of stars in spiral galaxies. Thus the conjectured ‘cold dark matter’ which interacts only gravitationally.

Scott notes:

But when man’s opinions about any thing which happened 6000 years ago or less are supported by devine revelation (and contradicted by observation, mathematics, and reason), they are completely infallible.

Isn’t that supposed to be Divine revelation? Especially Divine demonstrating the big bang. Nothing like a good John Waters movie to break the tension.

Delta Pi Gamma (Scientia et Fermentum)

6/6/06 is the day of the Beast. The Rapture will take place on the Lord’s day 7/7/07, ie. next year, being seven years after the millenium. Of course, if it doesn’t happen then, then there’s 23/12/12, when the Mayan calender runs out, or sometime in 2018, 70 years after Israel was founded, or after that.…

The number of times that they use the word assumption, actually makes me think that they believe that all science is based on assumptions (except their interpretation of the bible of course).

I’ve completed and passed an Open University course on Astronomy, and there was a section of it which covered basic cosmology, such as whether or not the Universe is open or closed ie what will be the eventual fate of the Universe ? The teaching videos that came with the course were really excellent and dealt with most of the subjects that Jason Lisle has rubbished in his article, like stellar evolution, determining the distances to astronomical objects etc. The thing that really amazes me is that Jason Lisle describes himself as an astrophysicist. When I read this piece of nonsense I wondered what type of answers he gave when he was studying for his degree/PhD. I’m sure they were nothing like the ideas he has expressed in his AIG feedback essay !

6/6/06 is the day of the Beast.

boy it sure was! I’m still getting over the hangover.

Peter Henderson wrote

I always thought that distant starlight was a problem for YEC’s but apparently not.

Henry Morris took care of that 35 years ago. He proposed that light from stars that appear to be more than 6,000 light years away was actually created on its way to earth. He accounted for observations of distant novas by postulating that the star that supposedly went nova never really existed, but the “blob” (Morris’ word) of light indicating the occurrrence of a nova was created en route to earth – the star was never really there.

RBH

Oh you who doubt the mark of the beast and the coming rapture (by the way can I have your car when it comes?) the next certain end of the world will be 6/6/2013. If you add the digits of the year it comes to tada!!!-06. If that doesn’t end the universe Pat Robertson can leg-press your body from here to the asteroid belt.(usually reliable sources say he can -with some cheating- leg press 1000 pounds!).By the way I’ve met the antichrist and his name is Wayne Allard.

It IS kind of interesting that galaxies are observed to spin faster (and cohere better) than a best-guess extrapolation (based on our limited knowledge of local conditions) allows. OK, so maybe Newtonian and Einsteinian physics have made some invalid simplifying assumptions (or we’ve done so to make the equations tractable) and galaxies are NOT best modeled as one huge gravitational point source at the center orbited by gravitationally insignificant satellites. Maybe galaxies obey known equations after all, if we redistribute the mass according to (again) extrapolations based on best observations of local conditions - even if this condition is hard to model.

Still, the notion that 85% (!!) of the total mass-energy of the known universe is composed of “dark energy”, without any clue what that IS, is discouraging. Does “dark energy” mean *anything* beyond “something we need to insert into our equations to make them match observation”? How would we ever test for this stuff? It sounds a lot like “we just don’t understand”.

Still and all, even thinking of finding answers to these questions in the Bible exceeds any useful concept of sanity. Instead, I submit that these folks don’t understand the issues and don’t see any utility in doing so. As Sagan wrote, their world is haunted by demons.

So fine, these folks are surrounded by an impermeable bozone layer. But help me out here anyway. What IS dark energy? How would we detect it?

Flint asked: What IS dark energy? How would we detect it?

Take one bible, a foreskin collector and a child less than 7 years old , beat until firm, wash child’s mouth out with soap if any awkward questions arise. Any questions?

From the AiG article:

We also know that stars that begin as gas and are then compacted into protostars and then become full fledged stars on the mainsequence for millions of years.

This is not known; it is blindly assumed by those who reject biblical creation. Have you or anyone else ever observed a star form? It supposedly takes millions of years (in the secular model), so no one could actually observe it even in principle. Those who believe in the big bang and secular models of star formation have no observational evidence that these things have occurred nor is there any sort of recorded eyewitness account.

[snip]

The proton-proton cycle turns hydrogen to helium in a star

Although this is not directly observed, we do directly observe the neutrinos that are produced in the process. So we have good scientific reasons to accept this theory.

These two quoted portions seem at odds with each other, unless I’m just missing or misinterpreting something.

In the first quoted portion, AiG states that if no direct observations of object or event X (in this case, X = the view of star formation as presented by S.D.) exist, and there are no eyewitness accounts of X existing/occuring, then belief that X exists or has occured is a “blind assumption.”

However, in the second quoted portion, AiG seems to realize that the above is not true; that just because X (in this case, X = the photon-photon cycle) hasn’t itself been directly observed and there are no recorded eyewitness accounts of X, that doesn’t necessarily mean that there cannot/do not exist good reasons to believe that X exists or has occured.

To me it appears that the “You haven’t directly observed X? There are no corroberatin eyewitness accounts of X? Then your belief that X exists/has occured is a blind assumption!” argument is not used consistantly by AiG.

If they did use this argument consistantly, wouldn’t AiG have to conclude that “the proton-proton cycle turns hydrogen to helium in a star” is a “blind assumption”, since there are no direct observations of this cycle (at least according to them; I have no idea if this is true) and no recorded eyewitness accounts of it?

The difference AiG sees is that we have indirect observed evidence of the fusion process, i.e. neutrinos. Apparently they don’t think you can use indirect evidence to support the formation of stars, despite plentify observation that lead to the conclusion of star formation. What the article really says is that, since nuclear fusion doesn’t violate their interpretation of Scripture, they’ll allow that it happens as described. It’s still fundamentally inconsistent because the nature of fusion in relation to a star’s operation is something we can use to determine the approximate age, distance, composition, etc. of stars.

Flint:

I wanted to respond to this:

Still, the notion that 85% (!!) of the total mass-energy of the known universe is composed of “dark energy”, without any clue what that IS, is discouraging. Does “dark energy” mean *anything* beyond “something we need to insert into our equations to make them match observation”? How would we ever test for this stuff? It sounds a lot like “we just don’t understand”.

‘Dark energy’ is best thought of as a label for a set of observations that don’t make sense but do tie together. The most direct piece of evidence is based on supernovae (the explosions of massive stars) - see http://supernova.lbl.gov/PhysicsTodayArticle.pdf which appear to be further away than they should be. There are other lines of evidence that agree with these results (for example, from studying the large scale structure around us in surveys like this one - http://www.mso.anu.edu.au/2dFGRS/ These observations taken together seem to confirm that the observed expansion of the Universe cannot be accounted for by matter (dark or otherwise) and we call the extra component ‘dark energy’, a name which I think is deeply confusing.

It is fair to say that we lack a sensible theoretical understanding of what ‘dark energy’ might be; it could appear on either side of Einstein’s equations - ie as a component of energy or a modification to gravity. Further observations are needed to get a grip on its physics and test theoretical ideas, but it does seem to be here to stay.

Sorry to be so OT, I thought it was worth adding to the pot.

Well, we know dark matter exists, we’re made of it, and the planet we’re standing on is also made of it. We also detect particles of dark matter all the time. The real dark matter question is what type and quantity of dark matter is needed to explain our observations? I know it’s a pedantic point, but it seems that most people don’t realize that dark matter really means matter that doesn’t emit light, like rocks, or planets, or neutrinos. It doesn’t necessarily mean weird stuff we’ve never seen before. (unless you want to throw black holes into the weird stuff category)

No, baryonic dark matter, the sort of thing that comprises rocks, etc., is only about 4% of dark matter, and neutrinos don’t qualify because they don’t clump. “dark matter” primarily means “weird stuff” like SIMPs and WIMPs.

Lastly, Lenny, if you look at an HR diagram, you’ll see that red giants (and supergiants) are generally higher on the diagram than the main sequence, indicating that they are more luminescent, even though they are cooler.

Thanks. It’s been a long time since I’ve looked at an HR diagram.

Carol is correct!!!

Ah well, even a stopped clock is correct twice a day.

;)

Of course, I am correct. I usually am. Even Lenny will confirm that.

You are seriously delusional, Carol.

Caveat: this is how I remember it from 1st year astronomy:

Red giants are larger, but cooler. They radiate more infrared and less visible light. So they do radiate from a larger surface, but the total energy has decreased. Makes sense from a nuclear standpoint: helium fusion releases less energy than hydrogen fusion.

So, Carol, in short, my answer would be “not yet”. The star would fade, even though it is in fact larger.

If the graviational energy of the red giant overcomes the (decreasing) radiative energy, the star collapses and brightens again. That’s where you’d get yer nova.

“gravitational”, of course.

Graviational energy is when you gain weight at Thanksgiving.

Glen Davidson Wrote:
William E Emba Wrote:

Sure. But you quote-mined Carol, who actually had a whit more complicated assertion than the “mere speculation” that you mocked and criticized. Her assertion could be good or bad as a philosophy of science argument, but you did not address it.

It is not “complicated”. It was a glib assertion, arguably not worthy of comment.

It changed the meaning of her comment. She said something definitely more sophisticated and nuanced than “mere speculation” that you mocked her for supporting. Ergo, you quote-mined.

It had no bearing on the need for evidence that is needed for the acceptance of theories,

Which she didn’t deny, and which thereby reduces your garbage to a strawman. That you repeat it when it is pointed out makes it as blatant and deceitful as any creationist trash.

“Usefulness” is the strawman, which you can’t see around to understand the relevant issues.

She said it, you omitted it, thereby changing what she wrote to make cheap shots possible, which you engaged in and which you continue to support.

I didn’t address “usefulness” because it answered nothing at all regarding the necessity for evidence.

Who cares? My assertion is you mocked Carol for something she did not say or support.

You are being disingenous here. I was criticizing you for not addressing Carol’s actual argument.

It’s not an argument.

Of course it is. If it’s wrong, then say it is wrong. If it’s simple-minded trivially wrong, then let us know. But don’t lie about it, change Carol’s argument, and attack the made up strawman. Sheesh.

It requires a truly simple mind to suppose that bringing up “usefulness” addresses the purported need for evidence for a theory to exist (for instance, to compete with another theory that explains the evidence). It is because you yourself resort to such tripe that you insist that I should have addressed the non sequitur used against the claims that evidence is necessary.

I bring it up because I am pointing out your distortion. You’re now playing the typical creationist heads I’m right, tails you’re wrong, nah nah nah game.

It was quite blatant on your part.

That I blatantly ignore meaningless arguments often enough is true. Why shouldn’t I?

The meaning was inherent in what Carol said. You changed that meaning, quote-mining a strawman into existence. Sheesh.

There was nothing nuanced about your choice of “mere speculation” as a quick summary of Carol, and there is nothing I omitted that suggested such a choice of words on your part was actually not an incompetent hatchet job. The words you think I should have quoted do not in any way shape or form address this inaccuracy of yours.

Sorry, the words I wrote were relevant to the overall issues, which once again you are oblivious to.

You don’t get to quote-mine and then claim you’ve accurately summarized Carol because those are the issues you’ve decided are worthy. You are more than welcome to discuss what you want to discuss, but don’t attribute the “mere speculation” line to someone who obviously did not propose such.

I mentioned the “omission” because all of us, including you, use partial quotes primarily for the sake of reference, not because we’re trying to hide something. You accused me of “omitting” something that I found not worth addressing as it had been written.

And which had the effect of changing the meaning of what Carol wrote from something clearly not “mere speculation”. That’s called quote-mining.

Perhaps it is time that you learn that others find different things worth addressing, particulary those of us who understand science criteria than what we see in your posts.

It’s still quote-mining.

Those of us who know that “usefulness” per se hardly eliminates the need for evidence don’t have to conform to your groundless belief that it “addresses” the evidence issue.

Which wasn’t Carol’s claim, or mine.

If it is a “reasonable stance” it should be argued as one.

Why? Because you say so? Because you own philosophy?

Throwing “usefulness” against the claims that evidence is needed to back up a theory is not an argument,

It wasn’t thrown against it.

it is a meaningless assertion, one that you repeat.

Liar.

Again you lie about the “quote mine”. It is absolutely wrong to claim that just because someone brought up “usefulness” that it addressed the issue, and that it was worthy of comment in return. Though I don’t particularly expect you to understand that, or you would have in the first place.

Her original comment looked nothing like “mere speculation”. Your elision made it seem much more like “mere speculation”. That is all.

You just don’t like it that your simplistic approach isn’t treated as authoritative.

I made no such claims. You are simply lying deeper and deeper to cover your quote-mining buttside. I don’t like quote-mining.

I don’t expect you to. But perhaps you can treat philosophers of science with the same respect you treat biologists?

Only if they address the issues, instead of using non sequiturs as if they legitimate arguments. But because you use non sequiturs as if they were legitimate arguments, I don’t expect you to understand these matters.

These are just lies on your part.

Btw, it is your lack of regard for logic and philosophy that most annoys me here, well, after the dishonesty of claiming that ignoring a useless argument constitutes quote mining.

You changed the meaning of her words. You quote-mined. Pure and simple.

The great majority are not Popperians. It really is a subtle issue,

Apparently there is too much subtlety for you in the concept that up to the present moment all, or very nearly all, theories to the present have required evidence to be considered in science.

I have never suggested otherwise. You have to invent more and more outrageous and blatant lies, just like the creationists, to cover your nonsense.

Your confusion of choosing between two theories that explain the evidence with the need for theories to be supported by evidence is not attractive.

Entirely a strawman on your part.

How very stupid of you. Intelligent people do not always address non sequiturs, and your inability to understand that “usefulness” does not address the need for evidence shows that once again you are projecting your egregious mistakes.

It wasn’t a non sequitur, and I never denied the need for evidence. You are simply inventing things left and right.

Do you think that I missed the “usefulness” criterion that she mentioned?

No. I think you omitted it and created a strawman. Sort of like what I’ve been saying?

So an excerpt constitutes “omission”. Perhaps it is time for you to recognize that excerpts do result in omission, and that ignoring non sequiturs is reasonable in many circumstances.

Yes. But it wasn’t a non sequitur, and you changed the meaning, so in this case, the omission was not acceptable for argumentive purposes. That’s why there’s quoting (with excerpts and omissions totally acceptable), and there’s quote-mining.

I made no claims as to what I believe, beyond what philosophers of science have noted for decades: the philosophy of science is very difficult, and in particular there are no simple on-off switches, with EZ-REED labels like “falsifiability” and “paradigm shift” that demarcate science from pseudoscience.

As I indicated as well. Still, you insist that I should have treated an unbacked statement as if it had addressed the questions raised.

It was an assertion which you quote-mined, turned into something different, and for mocking strawman you got criticized.

And still you utterly fail to demonstrate how “usefulness” obviates the need for evidence.

A strawman on your part. Who said it did? Sheesh.

She did not claim “mere speculation” passes the bar. You mocked her for saying so.

Of course I didn’t.

Of course you did.

Once again your inability and/or unwillingness to honestly address the issues rears its ugly head. I didn’t claim she said that “mere speculation” passes muster, I wrote:

IOW, Clouser’s firmly with the IDists in trying to redefine science into something that includes mere speculation into its definition.

It’s obviously an interpretation, and one that was based upon past statements. I’m sorry to be repeating these things, and would rather play nice with her, but that is what I said. Yours is merely a false claim.

No, yours is. Carol’s statement wanted usefulness to be included. Your version leaves it out.

I was mocking her for not actually addressing the issue.

You were mocking her for something she did not say.

But that’s over (I hope), and now I will simply mock you for claiming that “usefulness” addresses the claim that evidence is necessary for any theory to be properly accepted.

Which is not something I said either.

You don’t seem to get it through your head that there are good philosophical means of addressing issues, and that yours fails utterly to approach the level of philosophy, or even of decent meta-science.

Well of course. I’ve been addressing your disgusting pathetic creationist like tactics of quote-mining and strawman refuting. Sheesh.

Well, Bill, I did glance at your BS after all. Since you can’t and don’t intelligently support anything that you say (at least the little that I read–I’m not going to go on reading mere lies and false claims), I really don’t have anything substantive to add. I can only register my amazement at your inability to understand, and at your mendacity.

Apparently all you can do is repeat your falsehoods. Well do it then. I have explained things in my posts, and you seem not even to understand explanation any more than you do science, linguistics, and philosophy. Your stupidity and dishonesty is harmful primarily to yourself, and only mildly to others.

And now I probably am out of this thread for good. There can be no value in tangling with someone who has so little regard for understanding and truth as Emba reveals himself to be in his posts.

Glen D http://tinyurl

Well, Bill, I did glance at your BS after all, since I was a bit bored and a bit curious. Since you can’t and don’t intelligently support anything that you say (at least the little that I read–I’m not going to go on reading mere lies and false claims), I really don’t have anything substantive to add. I can only register my amazement at your inability to understand, and at your mendacity.

Apparently all you can do is to repeat your falsehoods. Well do it then. I have explained things in my posts, and you seem not even to understand explanation any more than you do science, linguistics, and philosophy. Your stupidity and dishonesty is harmful primarily to yourself, and only mildly to others.

And now I probably am out of this thread for good. There can be no value in tangling with someone who has so little regard for understanding and truth as Emba reveals himself to be in his posts.

Glen D http://tinyurl.com/b8ykm

Lenny and STJM,

Of course I was kidding. But that does not mean what I said was not correct.

For those of you wondering what an HR (Hertzsprung-Russell) diagram is, I submit my class website: http://inst.sfcc.edu/~gmead/Stars/stars.htm

Caveat: The website was created for Freshman-level non-science students, has been simplified, and is my understanding (as a general Earth Scientist, not an astronomer) of what is correct.

BTW: My understanding is that a nova (“new star”) is generally considered to be a sudden (days to months) phenomenon. The transition to a red giant from a normal main-sequence star would undoubtedly take millions of years (AFAIK) so would never be considered to be a nova, even if it did become brighter over that time interval.

fnxtr: Although He-fusion does release less energy, the star still has a high temperature in the core: ~100 million K, vs. ~14 million k for a yellow H-fusion star. This leads to H fusion in the outer envelope. The cooler temperatures at the surface are more a result of the larger surface area than the total energy released. And the temperatures are not insignificant - about 3000 k for a red star vs. 6000 K for a yellow star.

Roger that. Thank you for the clarification.

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This page contains a single entry by Nick Matzke published on June 8, 2006 11:49 AM.

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