Talk:Solar core



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 * The following discussion is an archived discussion of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section. 

The result of the proposal was consensus against move.--Fuhghettaboutit (talk) 07:17, 11 January 2009 (UTC)

Requested move

 * It has been proposed below that Solar core be renamed and moved to Stellar core.

Is there some data other than speculations based on star models? BTW the solar neutrino problem is a separate article. Also, in Lithuanian Wikipedia the corresponding article is named lt:Žvaigždės šerdis (star’s core). Incnis Mrsi (talk) 10:56, 6 January 2009 (UTC)
 * So? We are not obliged to follow the layout of another Wikipedia; we could use a wider article on all stars if the figures are published, but these are for Sol, not, say, Rigel. Septentrionalis PMAnderson 19:26, 6 January 2009 (UTC)


 * Oppose this article is about the Sun, not some generic core of a star. 76.66.198.171 (talk) 05:17, 7 January 2009 (UTC)


 * I also oppose this change, as (a) we know by direct observation (via neutrino measurements, & helio-seismology) a lot of specific details about the internal structure of the Sun which we must infer almost entirely from theoretical modeling for stars; and (b) stellar cores vary tremendously over the range of stellar types, from newborn O stars to pre-supernova Wolfe-Rayet stars to M-dwarfs. The current solar core article is really just about the Sun.  If we had a good article on stellar cores, surveying all the known types, we might well include a section describing the Sun's core as an example, but it seems premature to me until we have the latter.  (I have posted essentially the same remark on the astronomy and astronomical object discussion pages, but I suppose the discussion should be at one place, here?) Wwheaton (talk) 07:48, 7 January 2009 (UTC)
 * Yes, this is the centralized discussion area, WP:RM always hosts its discussions on the talk pages of the articles in question (or one of the set of articles concerned). 76.66.198.171 (talk) 18:49, 7 January 2009 (UTC)


 * Oppose. "The article should have more general scope." Incnis Mrsi (talk) 11:00, 6 January 2009 (UTC) Change the article, then request the name change. —   AjaxSmack   21:38, 7 January 2009 (UTC)


 * Oppose. It's a good topic and a good article. Why destroy it? Far better to write a new article on the more general topic of stellar core. And as observed above, you'll find the information on the more general topic far more speculative, the parameters enormously variable even within a single theory, and the article far more challenging to write well. Andrewa (talk) 13:15, 8 January 2009 (UTC)


 * Oppose Stellar core is enormously diverse topic. The cores of different stars may have very little in common. How can the core of Sun, where hydrogen burns into helium, be compared to the degenerate (and essentially dead) core of a red giant (or AGB/SAGB star)? Or to the iron core of a presupernova? Ruslik (talk) 17:12, 9 January 2009 (UTC)
 * The above discussion is preserved as an archive of the proposal. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

questions:
since the sun is now 20% helium by volume, how can any hydrogen penetrate this gigantic ocean which must be below the lighter hydrogen? — Preceding unsigned comment added by 47.200.181.61 (talk) 22:47, 5 March 2020 (UTC)

i think solar physics is a pretty interesting subject but find some of the information/facts here to be a little strange. the comparison of the sun to a active compost heap seems to be a little far-fetched. as well as the comparison to reptile metabolism. these references either need to be substantiated and placed in context or removed. also, as it relates directly to most of the physical processses relevant to the solar core, it might be useful to have some explaination of the gravitional/electro-magnetic forces in context that are at work in producing the core. also, i am not sure that some of these numbers are correct. the numbers referred to in 'photon travel time' of 15k to 5million years can't be right. the numbers provided in this article and others for the chemical composition of the sun also do not seem accurate. (looks like a article that could use some work...) 131.230.224.28 (talk) —Preceding undated comment added 22:36, 1 August 2010 (UTC).
 * The fact that you think they are far-fetched is exactly the reason they need to be there. Your own metabolism is volumetrically considerably higher than the heat production at the center of the Sun. If you pick the animals that make only 300 watts/cubic meter, you miss all the mammals except perhaps elephants and rhinos. 30 watts/100 kg is about the metabolism of alligators. So what metaphor do you like?

Compost heap: http://www.bautforum.com/archive/index.php/t-97184.html

S B Harris 23:26, 1 August 2010 (UTC)

-- but 'volumetriccaly higher' gives no real indication of the time-frame or scale or nature of the interactions that are occuring. and the comparisons would be misleading-- the metaphor would be suggestive of something like :: 'the sun is not very hot'. which many people would find perplexing. if you really want to drive home this comparison it will require more substance and support. (but i have to confess that because i have no personal, empirical understanding of the volumetric combustion/fusion reaction of the sun beyond stepping outside on a sunny day that i cannot make a arguement well-grounded in mathematical reasoning. also i am not sure of the accuracy of the simplification of 'watts to cubic meters' as my understanding is that metabolism could be more accurately measured on both a different scale and in different terms? but you are saying that the 'wattage' in question is relevant to both energy produced as well as, i suppose, metabolization of molecular energy into proteins ?? i'm not sure that the comparison between solar fusion and organic metabolism is perfect). -sio. (talk) 16:20, 2 August 2010 (UTC)
 * The MECHANISM for how the heat is generated is a completely separate question; here we're only interested in how much. Metabolism can refer to the chemical reactions, or just to the heat output (I've changed the text to specify which). Your body makes over 100 watts in 0.1 cubic meter (your volume if you weigh 100 kg). Often this is expressed in Calories=kcal per day (100 watts = 2065 kcal/day), but watts is the metric equivalent. The "time frame" is explicitly a part of expressing things in powers vs. energies, and the scale is taken care of by expressing power as an intensive quantity. Power density can be per mass, or per volume. A person-sized bit of the core of the sun generates less than 30 watts, but a person-mass of the sun's center generates less than 1% of that, due to the very high density. I can only suggest that you get up to snuff on your basic physics, which this article requires you know (definitions of heat, temperature, power, energy, volume-specific power, etc.). Above you say that "the numbers referred to in 'photon travel time' of 15k to 5million years can't be right." How do you know THAT? Perhaps your "common sense" ideas are off?  That's not surprising, as the center of the Sun is quite unlike anyplace you're used to. You've never seen anything with a density of 150 times that of water, either.  S  B Harris 18:59, 2 August 2010 (UTC)

Well-- my familiarity with some of the numbers here is not great, but with some of the solar flares that being reported as of August 1st being in the range of millions of kelvins, that seems significantly beyond any anything the human or any animal metabolism is capable of, even in scale. I think an accurate comparison is difficult to achieve here, especially using the 'volumetric' method, as you say, and it might be easier to start with with the energy produced in similarly small levels (energy produced by basic solar reaction vs. animal metabolism) and then to provide the volumetric scale to place it in context. Also, the ability of the human body to generate power does not seem consistent: surely my hair and skin and bones do not produce/expend the same amount of energy as more metabolically active areas, so why would the volume/power ratio be useful? (and how if sun-spots are reaching 1-2 million kelvins is it possible that the core which is, as you say, under a great deal of pressure and so very dense, only producing 30 watts?... I'm not sure that really stands to logic, but I have no 1st hand information of the energy-production of the solar core, myself.)-sio. (talk) 22:35, 4 August 2010 (UTC)
 * We use averages because they're average. Sure, different parts of your body produce heat at different rates, but you do have a pretty good idea of the average heat production of your body, and that volume of the solar core would only produce 30% of that, or less. As for temperatures, they are a sign of what direction heat flows, but they don't tell you anything about energy withough knowing mass and heat capacity. The thermosphere high in Earth's atmosphere reaches 2500 C in the day, but is so close to vacuum (about 1 millionth of an atm) that you wouldn't be burned by it. The solar corona is 40 times hotter, but has a density of only 1/100 trillionths of an atm, so again there's not much energy/volume, and you wouldn't be burned by it. The entire corona is powered by a solar output of 1000 watts/meter going up through it (1/40,000th of the solar output), which is the same as falls in your local desert, a lot farther away. But this little bit is absorbed by a column of thin gas several times the radius of the Sun, so you see there's nothing in there to get burned WITH, because the energy powering it all is so pitiful (again, it's very close to the power of sunlight at the distance of the Earth). If you were sheilded from Sunlight from the sun, you'd have no problem with the heat or glow from the corona, even if you were inside the Corona, because it absorbs almost nothing. Now, why is the center of the sun millions of degrees, the "surface" 5500 degrees, and the Corona millions again? Well, obviously there's some kind of disconnection that carries energy directly to the corona by some mechanism other than simply heat conduction. It's probably some kind of magnetic induction heating, such as would cause a coil to heat over a magnet, without heating the space between (which in this case is the chromosphere). S  B Harris 23:33, 4 August 2010 (UTC)

No mention of Quantum Tunneling?
The core of the sun isn't actually hot enough to sustain nuclear Fusion. Under classical physics, there simply isn't enough energy to overcome the electromagnetic resistance of the protons to force the hydrogen nuclei together to make helium. Instead the particles have to quantum tunnel into each other, which means they randomly pop into existence at just the right spot so that nuclear fusion can happen.


 * Well, it means that when 2 protons approach each other, sometimes they can approach more closely than their temperature and potential would let them. That gets them inside the nuclear binding range. Even though, the main problem is that one of them has to beta decay before they can stick, and they don't stay together that long. Protons in the core have half lives of a billion years. Once they turn into D and He-3, that goes down to minutes or seconds. Yes, all this should be mentioned. Some of it is already in proton-proton fusion. S  B Harris 02:18, 13 November 2014 (UTC)

Dr. P.M. Robitaille
Expert on the Sun, its corona & chromosphere, photon interactions, spectrum analysis of materials, etc. Dr. P.M. Robitaille gives a lecture. https://www.youtube.com/watch?v=0Lg5eR7T61A&feature=youtu.be&t=2558 This page could do with information gained from this person. 14:34, 30 November 2015 (UTC)~

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Weird text on the solar core.
The bizarre text speculating on the iron-nickel composition of the solar core as an extrapolation from the core of Earth should probably be excised from the article, it reads poorly and communicates little. — Preceding unsigned comment added by 70.18.13.214 (talk) 16:07, 6 January 2022 (UTC)

I concur, and I removed it. 70.167.89.2 (talk) 00:32, 7 January 2022 (UTC)

Helium fusion
There's no mention of the triple alpha process anywhere. 74.135.194.87 (talk) 16:42, 27 January 2024 (UTC)