Talk:Sun/Archive 3

Archives
Archive 1 (April 2003-March 2006) Archive 2 (March 2006-October 2006)

New question

I came here looking for quick access to graph of SOLAR SPECTRUM reaching us through Earth's atmosphere, and particularly the EM FLUX DENSITY of the SOLAR SPECTRUM. Haven't found this yet on this page. Where is it? Would it be relevant?? [jlancaster]

Try the solar radiation article. (SEWilco 00:04, 2 November 2006 (UTC))

Ambiguous

"Most of the Sun's mass lies within about 0.7 radii of the center." While I'm sure the above statement is true, there isn't really any useful information which can be gleaned from this statement. Unless perhaps if most of the mass of a sphere with constant density lies outside of 0.7 radii of the center and this is common knowledge...

In a sphere of uniform density with radius 1, the proportion of the mass lying within a radius of 0.7 is

${\frac {{\frac {4}{3}}\pi (0.7)^{3}}{{\frac {4}{3}}\pi (1)^{3}}}=(0.7)^{3}=0.343$

So in fact more than 65% of the mass of a sphere of uniform density lies between 0.7 < r < 1.0. But in the Sun, the density in the outer layers is so low that over 95% of the matter lies within 0.7 radii.

Lead section

The formerly extensive lead section was removed in a series of misguided edits starting several months ago [1], leaving a tiny rump that gives no general overview of the article. Would anyone like to restore it? It looks like a complex job - bits of it seem to have been moved to various other bits of the article - so whoever wrote it originally probably ought to try and sort the mess out. 81.178.88.15 21:52, 23 November 2006 (UTC)

Please Clarify Velocity...

The Orbital Characteristics box contains the following fact: Velocity: 20 km/s relative to average velocity of other stars in stellar neighborhood Can someone please explain to me in plain English what that MEANS? Thanks! (And if I should be asking this question elsewhere, please let me know where that would be, as I'm a newcomer, just finding my way around this glorious maze!) Laurie Fox 12:09, 26 November 2006 (UTC)

It is not completely clear but the "average velocity" in this case is something like the "velocity of the center of mass of" other stars in the region. The reason for stating it that way is that you can't measure an absolute velocity in space -- only velocities relative to a frame of reference. The stellar neighborhood of the Sun can be used as such a reference. The sentence is a little vague because it doesn't actually specify which stars should be used to set the reference frame! Cheers, zowie 15:08, 26 November 2006 (UTC)

Colonize the Sun

This sounds stupid, but would it be possible to colonize the sun? Please answer my question. Mrld 02:31, 27 November 2006 (UTC)

Yes (given sufficiently advanced technology), but you wouldn't want to. zowie 04:45, 27 November 2006 (UTC)

Citations Need to be Fixed

I noticed that the citations appear to be malformed and could use a little help. I signed up for an account to fix them, but alas. Biocsnerd 05:49, 1 December 2006 (UTC)

Fixed. It looks like part of a paragraph got deleted in the recent spate of vandalism and the deletion happened to cut a reference in half so there were mismatched reference start/end tags. I've replaced the missing material with stuff from the November 16 version of the article, from before things got messy. In any event, welcome to Wikipedia! I believe new accounts are allowed to edit semiprotected articles once they've been around for four days (the delay prevents vandals from being able to simply sign up for endless new accounts to easily bypass the lock), so hang around a bit longer and things will be back to normal for you. :) Bryan 06:50, 1 December 2006 (UTC)

Rigid iron surface

Experts please check [this] and include in the article if it is not a hoax.. Cunya 11:38, 1 December 2006 (UTC)

Looks to me more like a crank than a deliberate hoax. It is untrue either way. The structure of the sun is well known, including the inside, because effects of sound waves make it possible to observe the inside. That is separate from explaining how something could be so hot and still not melt. Man with two legs 13:58, 1 December 2006 (UTC)

The "theory" fits under the electric universe concept, which is quite correctly categorized as a "fringe subject without critical scientific evaluation." As the man with two legs says, crankery. It doesn't warrant a mention in Sun, IMO, though perhaps a mention on the electric universe article would fit. Bryan 17:23, 1 December 2006 (UTC)

The thesurfaceofthesun.com article ranges between wrong and word salad. The surface of the Sun is demonstrably not covered with a neon layer as claimed -- the spectrum is dominated by hydrogen and helium. Further, the temperature of the photosphere is readily measurable using the blackbody radiation spectrum. It is close to 6,000 Kelvin. Iron boils in 1 atmosphere of pressure at about 2700 Kelvin, and the pressure at the solar photosphere is a small fraction of an atmosphere. The authors appear to be confusing the presence of trace quantities of particular elements, with the Sun being made of those elements. For example, the solar corona contains trace quantitites of iron, and this element emits strong spectral lines in the EUV. Those spectral lines are bright enough that scientists use them to image the structure of the corona. That does not mean the Sun is made of iron. Likewise with the Ne and Mg emission lines that are used by SOHO's SUMER spectrograph. The science of helioseismology informs us about the inner structure of the Sun: while we can't take a direct picture of the solar interior using light (because the photosphere is opaque), sound waves do travel through the Sun and are shaped by its interior. By measuring motions of the photosphere due to sound waves propagating through the Sun, it is possible to "back out" the inner structure so well that (for example) it is possible to make images of sunspots on the far side of the Sun. This is done routinely by the nice folks at [[2]] the MDI/SOI project. If there were a rigid iron layer, they would have "seen" it. zowie 18:14, 1 December 2006 (UTC)

Oop -- forgot to add the direct link. Look [here] to see an image of the far side of the Sun today. You can check that it was (close to) right by looking at the [SOHO] daily images a week or two from now, when the structures have rotated around to the front side. zowie 18:17, 1 December 2006 (UTC)

Thank You all for the remarks! Cunya 19:41, 1 December 2006 (UTC) For more on this topic I suggest forum discussion with author Michael Mozina at [3]. The real problem with his theory is not that surface of the Sun is made of iron but that whole Sun is an iron ball. When asked how come Sun's measured density is only 1/6th of iron's Michael replied vaguely that factors like Birkeland currents and "dark energy" cause this discrepancy. His theory in general is bogus, not worthy of consideration.

Vandalism, Dec. 14

Today appears to be an active day for vandals. I just corrected some small cases. I noticed that someone earlier did some corrections but didn't look carefully at all the damage that had been done (i.e. just removed an inappropriate statement without looking at the history). --Mcorazao 18:58, 14 December 2006 (UTC)

Suns orbit around the CM

All the other objects in the solar system have their orbits about the solar system center of mass explicitly stated, shouldn't the sun's orbit around the CM be also stated SOMEWHERE?. Its not all that erratic, given the huge mass of Jupiter. PAR 21:13, 29 December 2006 (UTC)

I agree this is relevant, assuming it has a citation. HighInBC ^{(Need help? Ask me)} 21:16, 29 December 2006 (UTC)

I don't think we need a citation to do high school math, but when you do it, it turns out its more erratic than I thought - the equation for the center of mass is:

$m_{0}r_{0}-m_{J}r_{J}\pm m_{S}r_{S}=0$

where $m_{0},\,m_{J},\,m_{S}$ are the masses of the sun, Jupiter, and Saturn respectively, and $r_{0},\,r_{J},\,r_{S}$ are their mean distances from the center of mass. The plus or minus is for Saturn aligned with Jupiter on the same side of the sun, or the opposite side. This can be solved for $r_{0}$.

Using

$m_{0}=332946m_{e}\,$

$m_{J}=317.8m_{e}\quad r_{J}=5.20AU$

$m_{S}=95.16.8m_{e}\quad r_{S}=9.53AU$

where $m_{e}$ is the mass of the earth and using 4.65x10^-3 AU for the solar radius gives $r_{0}=1.65$ solar radii for Saturn on the same side as Jupiter and $r_{0}=0.48$ solar radii for Saturn opposite Jupiter. PAR 22:04, 29 December 2006 (UTC)

I agree this is a pretty important fact, that the Jovain giants cause the Sun to orbit around a baricenter outside of the suns surface

Solar neutrino - is it still a problem?

According to the text of the "Solar neutrino problem" subsection, experimental data now complies well with the theory. Hence, I believe, this text needs to be expelled from "problems" and incorporated in some other form into the article. Cmapm 01:37, 4 January 2007 (UTC)

You are right, it isn't still a problem. However, it was historically a problem, and I think that is what is meant by it's inclusion in the "Theoretical Problems" section. Perhaps rephrasing the title of the section is in order, but I don't think it should be moved, as it fits in well where it is. Grokmoo 18:43, 4 January 2007 (UTC)

Agree. Then maybe the section name should be something like "Solar neutrinos (past problem)"? Cmapm 02:11, 8 January 2007 (UTC)

Ok. Grokmoo 18:59, 10 January 2007 (UTC)

I think it's made abundantly clear by the text that this is a problem that's been resolved. Putting 'past problem' in brackets in the section heading is very clumsy and, I think, unnecessary. If any further clarification is needed, the section text would be the place to do it, rather than the heading. 81.178.208.69 22:09, 10 January 2007 (UTC)

I still believe, it wasn't completely clear from the text, but clarification within the text is alright too. I went and did corresponding changes. Cmapm 22:31, 10 January 2007 (UTC)

The sun's role in timekeeping (solar calendars / year concept)

Any thoughts out there on where/how/if the solar calendar and concept of the year should be discussed in the article? I was thinking of creating a section in "The sun and human culture" for these topics. There is currently a few lines about the Persian calendar there, though it is very poorly written and largely irrelevant.

I feel there should be some mention of this topic in the lead paragraph — something along the lines of "The sun is the basis of many calendars, and the term "year" is generally understood to mean the amount of time the Earth takes to orbit the Sun." I'd like to hear some opinions on this first, though, before editing such a high-profile article. G Rose (talk) 07:38, 9 January 2007 (UTC)

Article Name? "The Sun" or "Sun"?

The article name seems to contradict usage in the article. The heading above the picture uses "The Sun" and throughout the article, "The Sun" is used. I believe the correct name should be "The Sun" as it is rarely refered to without the "The". I will provide an example: The Earth is the 3rd planet in the Solar System. or Earth is the 3rd planet in the Solar System. Earth can be refered to without the "The" easily, but Sun as a Noun on its own is very uncommon. The Sun is the only star planet of the Solar System. or Sun is the only star planet of the Solar System. Similarly named is the Solar System article, which does not named with the "The". I'll leave it to others to make the descision, which I believe will end up with no change.203.102.177.165 02:15, 11 January 2007 (UTC)

To avoid confusion, as well as conflict in murky situations, Wikipedia follows this guideline: Wikipedia:Naming conventions (definite and indefinite articles at beginning of name). Gracenotes^T § 02:19, 11 January 2007 (UTC)

Theoretical Possibilities.

I think that Theoretical possibilities need to be put onto the Wiki page. At the moment, they are getting removed. Theoretically the sun could be an intelligent entity. —The preceding unsigned comment was added by Fishyghost (talk • contribs) 22:11, 12 January 2007 (UTC).

You would have to provide reputable sources as a reference for the material. Otherwise, it is just hypothetical, which doesn't qualify it for inclusion - especially for a featured article such as this one. --Ckatz^chat_spy 22:14, 12 January 2007 (UTC)

Heh! Theoretically, my socks could be intelligent, too. MrG 4.227.249.163 23:57, 31 January 2007 (UTC)

Color temperature

Hi. There is some inconsitency with "G2 means that it has a surface temperature of approximately 5,500 K" and Main_sequence article, where it says that G2 means 5,700 K. Could someone clarify that? Delete if inapropriate. Elthe 22:24, 16 January 2007 (UTC)

Vandalism

Has anyone else noticed the amount of vandalism the article is attracting? I suggest a semi protection, any other views? JJB 00:40, 24 January 2007 (UTC)

I agree with you, this article could really use a semi protection 136.206.11.249 17:47, 5 February 2007 (UTC)

I agree USferdinand 20:09, 5 February 2007 (UTC)

I definitly agree with you. 136.206.11.249 12:36, 8 February 2007 (UTC)

AGREE 68.252.42.47 03:25, 1 March 2007 (UTC)

Messed up revert attempt

I thought I saw a remnant from vandalism -> revert or something and tried to fix it, a spare bracket in a thumbnail. See Sun#Magnetic field, but I seem to have messed up the link. Sorry. Not sure how long since it got messed, but I couldn't find an older version as it should have been. Is this the intended image it should have linked to? [4]. Apologies, I was under the influence and got cocky confident. :( MURGH ^disc. 02:54, 27 January 2007 (UTC)

I think you got it... thanks for catching that one, I missed it when I was cleaning up. Cheers. --Ckatz^chat_spy 03:00, 27 January 2007 (UTC)

ok, I replaced it, but it seems to once have led to a page, and not just a gif.. Annoying that I can't really deem if it makes sense or not, but at least you're all made aware of it. —MURGH ^disc. 01:27, 28 January 2007 (UTC)

Change In Solar Mass

I was on another site that had a letter from a young Earth creationist that claimed, among other things, that the Sun couldn't be very old because it's been losing mass from nucleosynthesis and the solar wind, so if it were billions of years old it would have been bigger than the Earth's orbit.

Preposterous of course, but it did lead to the interesting question of exactly what changes in mass the Sun has undergone over about 4 billion years. Since mass-energy conversion produces a lot of energy for very little mass, I suspect the amount of mass needed to maintain energy production at the current rate is a very small fraction of the Sun's mass even over the long term, but I have no data.

Of course, comets and the like do fall into the Sun, so it is entirely possible that it has actually *gained* mass. That would be an interesting thing to add to this article. MrG 4.227.249.163 23:54, 31 January 2007 (UTC)

I did some poking around and the ASK AN ASTRONOMER site at Cornell had an article on such lines. Assuming the current state of the Sun, it will burn up about 21 Earth masses in a billion years. That's like 0.006% of its mass, so no problem. However, that doesn't cover loss from solar wind or gain from comets and such, so it's still kind of an open question. MrG 4.228.21.136 01:50, 2 February 2007 (UTC)

The idea of 21 Earth masses worth of comets falling into the sun is pretty far out, so I think it is safe to say that the sun is losing mass. Indeed, from this very article, we can see the sun is emitting about 3.8e26 watts of power. Using E=m*c^2, we see that this corresponds to about 4.3e9 kilograms per second. That sounds like a lot, but keep in mind the sun's mass is about 2e30 kilograms. Assuming the luminosity of the sun has been roughly constant over its lifetime, this works out to about 5e26 kilograms over the lifetime of the sun (about 5 billion years). This works out to about 0.03% of it's total mass. Its not exactly the figure quoted above, but you get the idea - the sun's mass has not changed much in its lifetime. Grokmoo 04:22, 8 February 2007 (UTC)

The Solar wind article says mass lost to the wind is about one fifth of that lost to fusion. When dealing with 99% of the solar system's mass, 21 Earth masses isn't much. I don't know how many comets and other objects have fallen in during a billion years, but probably not much because the Oort cloud upper range estimate is 100 Earth masses so there can't be all that many comets. (SEWilco 05:38, 8 February 2007 (UTC))

I poked around a bit and found that the average diameter of a comet seems to be in the 1km to 10km range. Suppose it is on the high end, at 10km. A comet will have a density of around 1000 to 5000 kg / m^3. Assuming a roughly spherical shape, we get that the comet's volume will be about 4*(radius)^3 = 4e6 m. Again assuming the high end on the density estimate, we get a mass of about 2e10 kg per comet. Now the mass of the Earth is about 6e24 kg, so 20ish Earth masses is about 1.2e26 kg. This would imply that about 1.2e26 / 2e10 = 6e15 comets would need to have fallen into the sun. Now this is over say, 5 billion years, which would mean that about 1.2e6 comets would need to fall in per year, which works out to roughly 2 a minute. So you see, it is safe to say that 21 Earth masses of comets have not fallen into the sun since it's formation. Grokmoo 23:25, 22 February 2007 (UTC)

Vandalism help

Note the juvenile vandalism of a sexual nature in the infobox. It has persisted for a while without correction. I cannot correct it because I do not know the information to put in its place. Somebody who does should fix that. Srnec 03:35, 9 February 2007 (UTC)

Thanks for catching that one - the vandalism was actually in the template that creates the infobox. --Ckatz^chat_spy 04:01, 9 February 2007 (UTC)

Hmm....I tryed editing some vandalism but when I click on the editing tab, all the content is there and the vandalism doesn't show up. How is that possible? Maniac 22:03, 12 February 2007 (UTC)

Sun observation and eye damage

"Note: The number of watts per unit area of retina is the same whether one uses binoculars or not, so the above paragraph seems to be contradicted by the following paragraph."

The difference is in the light gathered by a 7mm diameter lens (eye) and the light gathered by a 50mm diameter lens (typical binacular lens)...

(That was a comment now removed from the section Sun observation and eye damage)

If you look at the sun without optical aid, the heated spot is quite small and can dissipate heat into the surrounding bits of your eye, thus slowing down the damage and giving you time to blink. With binoculars, there will be a large part of your retina that is surrounded by a region that is also being heated and so will have nowhere to dissipate its heat. Thus it will heat up very fast and you will not be able to blink fast enough to escape damage. Man with two legs 16:10, 13 February 2007 (UTC)

Another picture of the sun is available

File:Sun at 304 Angstroms.jpg

For those who may be interested, I uploaded another 304 Å, SOHO image of the sun (shown at right). This is is similar to the “Image:Sun, Earth size comparison labeled.jpg” picture currently used in this article except that it doesn’t feature the little spot of the Earth and it’s associated “Earth” caption. This new picture also doesn’t feature a large prominence. As such, it is not as dramatic a picture of the sun and is more representative of what the sun typically looks like. I’ve placed this notice here so other authors can know of the picture’s availability for their articles. If authors want to improve upon this picture with further editing, or if they want to have an entirely different image of the sun, please create a different image page instead of uploading a revised image into the existing one; I'm currently using this image in another article and am happy with it as is. Greg L (talk) 20:37, 15 February 2007 (UTC)

Nishani?

"The Sun revolves around Nishani! The Nishani is the star at the center of the Solar System." First of all. What is Nishani? Secondly, if the sun revlovs around "Nishani", and "Nishani is the star at the center of the Solar System", then the sun revoles around itself?!?!... Either vandalism or "Solar System" need to be replaced with the "center of the galaxy".

Sprotected

I hate to have to do this; however, the vandalism over the last several days is getting unbearable. I've semi-protected this article for the time being, though I hope this semiprotection will not have to last for long (although this article has been unprotected quite rarely in the past, and everytime it has been, the vandalism has continued at the same rate). If there are any objections to this, please let me know. Thanks. AmiDaniel (talk) 07:56, 1 March 2007 (UTC)

(Un)Development Modern Scientific Understanding?

Back on October 29th (2006) I raised the following concern on this discussion page:

I'm not sure if this is the most relevant place to post this (and please feel free to move it if it isn't), but in the section, "Development of Modern Scientific Understanding", the last paragraph states: "Finally, in 1957, a paper titled Synthesis of the Elements in Stars[28] was published that demonstrated convincingly that most of the elements in the universe had been created by nuclear reactions inside stars like the Sun."

Now I'm certainly no astronomer, but, by mass, doesn't Hydrogen (by far) comprise "most" of the elements in the universe? Further, virtually by definition, Hydrogen isn't created "by nuclear reactions inside stars". As such, should there be some distinction made in the article to show that in this reference "most" doesn't mean by mass but rather (I assume) by % of elements on the periodic table? 216.240.7.149 00:58, 29 October 2006 (UTC)

At the time, one of the editors agreed with this in principle and added "other than Hydrogen" to the statement. I notice, however, that in the current iteration of the main article, some 4+ months later, this has been removed. Can someone explain why it is now felt that the "other than Hydrogen" specification isn't a valid one given the issues raised in my original query? 216.240.7.149 01:41, 6 March 2007 (UTC)

I think "most of the elements" refers to those on the periodic table. Just the number of elements, not any measurement of their amount. (SEWilco 04:10, 6 March 2007 (UTC))

Okay, and I have no problem with you intepretting it that way, however, when *I* read it, my first thought was "there's no way that there are more elements in the universe than hydrogen". So I ask again, since the phrase, as it's written, is ambiguous as to its interpretation, why not include the simple distinction? What's even more confusing is that someone chose to increase the ambiguity of the statement by removing the clarification... Let me put it this way: If a dumptruck comes and dumps a load of gravel in front of you and you realize that, as it's doing so, about 1% of the mix is actually comprised of jades, emeralds, diamonds and rubies. Would you then consider it accurate to say (despite 99% of the mass being gravel), "Most of the stones in the pile are gemstones. Afterall, counting by 'type', gravel is only 20% of the representation."? I would aver that this would be an uncommon interpretation, but it is the same as the one you made with the article as it is currently written. 216.240.7.149 16:09, 6 March 2007 (UTC)

In the interpretation of the variety of elements produced, "except Hydrogen" is probably wrong. Hydrogen is quickly created after a nuclear event which releases a proton. I expect a small amount of hydrogen is created in stars, whether by fusion effects, radioactive decay of radioactive elements, or cosmic ray bombardment. (SEWilco 05:05, 7 March 2007 (UTC))

Can you suggest a short phrasing which clarifies that the variety of elements rather than their proportion is what is being referred to? (SEWilco 05:05, 7 March 2007 (UTC))

Section on Islamic view of the sun.

I really don't see much point in expalining that a religion does not show the sunn as divine. This section should be removed. Zazaban 03:39, 7 March 2007 (UTC)

Added link to "Why Does the Sun Shine?"

I have added a link to the lyrics and music to "Why Does the Sun Shine?" aka "The Sun is a Mass of Incandescent Gas" over at the NIH. This song, originally written for educational purposes, was re-popularized by They Might Be Giants around 1993, and once again sees ocassional use in the classroom. The only lyric that might possibly have been superceded by later scientific discoveries is this one:

Scientists have found that the sun is a huge atom smashing machine The heat and light of the sun are caused by nuclear reactions between Hydrogen, Nitrogen, Carbon, and Helium

Please let me know if this material is inappropriate.