Talk:Sun

Template:WP1.0

Orbital Characteristics from Scientific American

In the November 2009 issue of Scientific American, Zwart (a theoretical astrophysicist) lists the sun's orbital parameters differently. I don't know where the ones in this Wiki article came from, so I can't vouch for their accuracy. Should we upgrade to the following numbers?

The relevant passage:
"At the moment, we are located about 30,000 light-years from the center and about 15 light-years above the plane of the disk [of the galaxy], orbiting at a speed of 234 kilometers per second. At this rate, the sun has done 27 circuits since its formation."

APA citation:
Zwart, S. F. P (2009, November). The Long-Lost Sibliings of the Sun. Scientific American. —Preceding unsigned comment added by 76.120.250.205 (talk) 18:26, 24 December 2009 (UTC)

Binary

Is our sun part of a binary, where the other has since died? —Preceding unsigned comment added by 82.132.136.203 (talk) 11:18, 9 October 2009 (UTC)

An interesting hypothesis. It may also be possible that our solar system is binary, however we are too far away from the other star to notice it.--24.171.1.195 (talk) 01:39, 13 December 2009 (UTC)

It is a hypotheses that is debated very seriously in the scientific community and there are a couple of major star surveys underway working to resolve the issue (most stars in our neighborhood have never had their distance from the Sun calculated, because this previously required labor-intensive parallax measurements). However newer technology is speeding this up and the search for the Sun's possible companion star is now underway through a couple of major star studies. See the Wikipedia article Nemesis (star) for more details.

By the way, the prospect of the Sun possibly having a small companion star in co-orbit around it (a Red or Brown Dwarf) is taken seriously enough in the scientific community that a small section on the theory merits addition to this article. The fact that two major astronomical star surveys are currently underway to prove or disprove the theory certainly rates at least a mention in this article.

75.166.179.110 (talk) 18:44, 21 March 2010 (UTC)

I disagree. Until there is greater evidence than there is now that a companion star exists in the Solar System there is no need to mention it in a encyclopedia article like this. We are presenting verifiable, referenced facts, not the speculative possibilities of science fiction.

Anyway, there is some real trouble with that hypothesis: first of all, in order to define this as a binary star system, the companion by definition would have to be a star. That eliminates brown dwarfs or substars like that from consideration. Such a body in orbit around the Sun would be considered a planet, if not, any of the four gas-giant planets, Jupiter, Saturn, Uranus, or Neptune could be considered a "companion star" of a multi-system.

Second, in order for a companion to be "stellar" it would necessitate a large mass, again by definition. The smallest know "normal" star is 93 times as massive as Jupiter (see Wikipedia article, "Star", under subsection "Mass"). Again, if the body was much smaller, so that it couldn't sustain nuclear fusion, it would be considered a planet. It is a bit hard to imagine a star as massive as that, located, say, within 0.5 - 1.0 parsec distance (where it wouldn't be perterbed away by nearby systems) having not already been discovered. Remember, the search for additional planets has been going on for centuries. Since the orbital barycenter of the Sun lies under its surface and much of this perturbation is explained by the existance of the known planets, it is hard to believe something else is out there.

Third, a main-sequence star, no matter how dim of a red dwarf, that close must have already of been detected. A more exotic object even if invisible in the visible light would likely radiate at other wavelengths. Even if it didn't radiate at all, seems to me its mass would have been detected by its gravitational effects.

I don't mean to take away from the research being made to verify this one way or the other, but obviously there is nothing to report yet. I see no need to publish it. GeoPopID (talk) 15:58, 28 March 2010 (UTC)

The Sun v. the Sun

If someone puts in 'The Sun' into the search box, they are more likely to be looking for the newspaper of that name not the celestial body. Sam Blacketer (talk) 15:51, 14 November 2009 (UTC)

You mean we should redirect The Sun to The Sun (newspaper)? I think it is better to create a dab. Ruslik_Zero 16:39, 14 November 2009 (UTC)

This was extensively debated in late July, with the consensus being to move the newspaper's article to The Sun (newspaper), redirect "The Sun" to "Sun", and use the "Sun (disambiguation)" hatnote at the top of the page. --Ckatz^chat_spy 21:48, 14 November 2009 (UTC)

Well, that debate came to the wrong decision. WP:THE is the guiding page and its application here is clear. I also dispute that the closer of the debate correctly determined consensus - certainly not on a pure vote count, and definitely not if established naming convention is given the greater weight appropriate. Sam Blacketer (talk) 22:54, 14 November 2009 (UTC)

If you feel that way, you can certainly ask for a review or a renewed discussion. However, it would not be appropriate to arbitrarily change the redirect without said discussion. I'd also point out that the earlier discussion did consider WP:THE, that the British paper (while certainly very popular) is not the only paper using that title, and that the original nominator actually changed his proposal in order to have "The Sun" redirect to "Sun". --Ckatz^chat_spy 23:09, 14 November 2009 (UTC)

I think it should be reopened per WP:CCC. The point about the naming guideline is that it ought to have far more weight in the issue; it's effectively up to those arguing a different outcome to contend why the guideline should be ignored on this occasion. The original proposer of the move actually made his proposal more extreme, given that he started by proposing The Sun as a disambiguation page. There might be a case for a separate disambiguation page for newspapers called The Sun given that there is no article on the former London evening paper (1792-1871). Sam Blacketer (talk) 23:27, 14 November 2009 (UTC)

With regards to WP:CCC, yes, of course consensus can change - but that is usually considered in regards to long-standing matters when significant opposition arises, not relatively minor issues that were debated and concluded a short time ago. With regards to the guideline, the consideration was that in this case, "The Sun" was far more commonly thought to refer to the star rather than the other references, let alone to a single paper. In part, that reflects an international perspective. --Ckatz^chat_spy 23:46, 14 November 2009 (UTC)

If someone puts in 'The Sun' into the search box, they are more likely to be looking for the celestial body, not the newspaper. South Bay (talk) 01:07, 17 November 2009 (UTC)

Obviously; it's odd that the OP thinks otherwise. -- 98.108.219.226 (talk) 00:45, 24 February 2010 (UTC)

rename article to Sol

Please move this article to Sol, the sun's official name. Sun can also refer to a different sun or the philosophically scientific explanation of suns.--24.171.1.195 (talk) 01:22, 13 December 2009 (UTC)

The Sun is the Sun's official name. It's only called Sol in science fiction novels. Serendi^podous 01:25, 13 December 2009 (UTC)

while the article should be called the sun, it is simply not true that its only called sol in sceince fiction novels. Outerstyx (talk) 15:40, 8 March 2010 (UTC)

Please stop making false -- and even ridiculous -- claims. There is no office responsible for the name of our star, so there cannot be an official name, but if you check an English dictionary you will find that it goes by "the sun" or "the Sun". -- 98.108.219.226 (talk) 00:53, 24 February 2010 (UTC)

Actually, the IAU is responsible for such matters; they are the ones who have clearly stated that the formal (i.e. official) name for the Sun in English is, well, the Sun. --Ckatz^chat_spy 06:32, 24 February 2010 (UTC)

editsemiprotected error? http://en.wikipedia.org/wiki/Sun

{{editsemiprotected}}

I have trouble reading the Corona section of page http://en.wikipedia.org/wiki/Sun. There may be a numeric error by a factor of 10 or others smaller. And a sentence with arithmetic seem out of order. Here is a replica of some of the text with my comments imbeded in square brackets. … the Sun releases energy at the matter–energy conversion rate of 4.26 million metric tons per second… Power density is about 194 µW/kg of matter, though since most fusion occurs in the relatively small core the plasma power density there is about 150 times bigger. [Last phrase not clear. Why is the arithmetic done a sentence later, or is it?] For comparison, the human body produces heat at approximately the rate 1.3 W/kg, roughly 600 times greater per unit mass. [But 1.3/194µ = 6701, not 600] [per unit mass of the sun as a whole or of the core?] Assuming core density 150 times higher than average, this corresponds to a surprisingly low rate of energy production in the Sun's core—about 0.272 W/m3. [But 150(194 µW/kg) = 0.029 not 0.272] This power is much less than generated by a single candle... Edtakken (talk) 02:56, 29 December 2009 (UTC)

 Done Welcome and thanks for contributing. That portion appears to be a pseudo-scientific editorial against fusion power. The cited NASA source does not contain those numbers, nor does the paper characterizing a candle include that figure for power. All of the fusion occurs in the dense core yet the figures try to distribute the power across the entire mass, with a nod to "the plasma power density [in the core] is about 150 times bigger". Thanks again, Celestra (talk) 16:41, 29 December 2009 (UTC)

Use of kilometres versus kilometers

The page is inconsistent. Kilometers is used five times. Kilometres is used once. Ckatz undid my change toward consistency and I'm changing it back to consistent. If someone wants to give me evidence that kilometres is the correct wiki standard, I'll change them all to kilometres but for now, I'm going with the majority standard inside THIS article. Friedlad (talk) 04:07, 7 January 2010 (UTC)

WP:ENGVAR#Consistency within articles agrees that the article needs to be consistent in its use of national varieties of English. The guideline that seems right to use here is WP:RETAIN. Whichever variety of English the article originally used should be the standard with which we are consistent. I'll go check. Celestra (talk) 05:43, 7 January 2010 (UTC)

The original (2002) did not have any words which are specific to a national variety. Until this edit last November, all of the national variations were American English (color instead of colour, kilometer instead of kilometre,...) It seems that Friedlad is correct to revert. Is there a option for the convert template to use the American spelling? Celestra (talk) 06:02, 7 January 2010 (UTC)

Solar System Barycenter diagram

While reviewing this article, I noticed that the diagram "Motion of Barycenter of solar system relative to the Sun" was a relatively poor quality gif file, the source URL was to a PhotoBucket account that is now disabled, and it was for the years 1945-1996. Therefore I created two new diagrams and uploaded them to Wikimedia for you: 1) File:Solar System Barycenter 1944-1997.png is a complete recreation of the diagram in the article with the same years and path to verify validity of my algorithms, and 2) File:Solar System Barycenter 2000-2050.png which is a more "current" diagram for the years 2000-2050. Feel free to use one or both of these public domain png files if you want to replace the older diagram. Larry McNish, Calgary Centre of the Royal Astronomical Society of Canada. http://commons.wikimedia.org/wiki/File:Solar_System_Barycenter_2000-2050.png http://commons.wikimedia.org/wiki/File:Solar_System_Barycenter_1944-1997.png 68.144.133.105 (talk) 12:51, 8 January 2010 (UTC)

Theoretical Problems Section Title

The title, Theoretical problems, strikes me as very strange. They're more like inconsistencies; the theories are wrong, the sun is right. Any ideas for changing the title? Friedlad (talk) 13:58, 12 January 2010 (UTC)

'Theoretical incongruencies' seems appropriate. It suggests the disagreement between theory and reality. 'Inconsistencies' strikes me as just as strange as 'problems.' —Preceding unsigned comment added by 216.85.157.42 (talk) 16:25, 18 January 2010 (UTC)

age of the sun

article indicates the age of the sun is 3.8-2.5billion years old. Recent Data suggests it is closer to 4.6billion years which is consistent with other measurements on the earth,moon,and meteorites. See "Standard Solar Model" wiki which references "^ Sackmann, I.-Juliana; Boothroyd, Arnold I.; Kraemer, Kathleen E. (November 1993). "Our Sun. III. Present and Future". Astrophysical Journal 418: 457–468. doi:10.1086/173407." —Preceding unsigned comment added by 70.138.186.72 (talk) 00:49, 16 January 2010 (UTC)

Source of visible light from Sun

The article is unclear as to the source of visible light emitted from the Sun. In the subheading Core, it states "After a final trip through the convective outer layer to the transparent "surface" of the photosphere, the photons escape as visible light. Each gamma ray in the Sun's core is converted into several million visible light photons before escaping into space."

However, in the Photosphere section, it says "The visible surface of the Sun, the photosphere, is the layer below which the Sun becomes opaque to visible light.[45] Above the photosphere visible sunlight is free to propagate into space, and its energy escapes the Sun entirely. The change in opacity is due to the decreasing amount of H− ions, which absorb visible light easily.[45] Conversely, the visible light we see is produced as electrons react with hydrogen atoms to produce H− ions.[46][47]"

The way I understand it, heat is transferred from the core to the photosphere, where the temperature is 5700K. The resulting blackbody spectrum at this temperature results in the visible light we see. How does the gamma rays get converted into visible photons (I'm guessing they are absorbed/knock off electrons and transfer heat that way), and how do "electrons react with hydrogen atoms to produce H− ions."? Can someone who knows this topic clear this up? —Preceding unsigned comment added by Kykw (talk • contribs) 06:15, 20 January 2010 (UTC)

Life Cycle

Under Life Cycle, it is noted "the Sun is gradually becoming more luminous (about 10% every 1 billion years), and its surface temperature is slowly rising. The Sun used to be fainter in the past, which is possibly the reason why life on Earth has only existed for about 1 billion years on land."

I am having some troubles understanding this...

As far as I can tell, for the most recent 4 billion years or so, the sun's luminosity has been fairly constant, and the earth's surface temperature has either been relatively stable, or slowly cooling.

So, if this is a predicted change from a past steady state to future warming trends, it should be noted as such.--Keelec (talk) 08:42, 21 January 2010 (UTC)

This is not a change from a past steady state. According to models, the Sun's luminosity has been increasing steadily for the past few billion years, and this will continue into the future. See e.g. Table 2, Sackmann et al., The Astrophysical Journal 418, 457–468 (Bibcode:1993ApJ...418..457S). Spacepotato (talk) 02:39, 23 January 2010 (UTC)

The Sun vs. the Sun (revisited)

The issue over where The Sun should redirect has been reopened. The original discussion in July 2009 led to a consensus to redirect The Sun to Sun. The new discussion can be found here. --Ckatz^chat_spy 21:08, 26 January 2010 (UTC)

Heavy rephrasing needed...

...with this bit at least.

The apparent magnitude of the Sun as seen from Earth is –26.74, which is of course the brightest object in the sky. The Sun is what lights up the daytime sky. Although the absolute magnitude of the Sun, which is the apparent magnitude as it is viewed from 10 parsecs away is +4.83.

Deleting the whole lot seems simplest (as both magnitudes are mentioned in the infobox), but most articles of bright or important Solar System objects indicate apparent magnitudes somewhere else as well. In my admittedly exceedingly humble opinion the Sun, on any Solar System scale, qualifies as both bright and important. The bit about absolute magnitude might also be worth keeping, as it helps in comparing the Sun with other stars.

I think this should be moved to the Observation and effects section after heavy rephrasing, but figured I'd seek consensus (and someone courageous enough to approach that mess and put it into words more neatly). Sideways713 (talk) 20:49, 28 January 2010 (UTC)

What about reversing the order as follows:

"The absolute magnitude of the Sun is +4.83. However, as the closest star to Earth, the Sun is the brightest object in the sky with an apparent magnitude of –26.74.

Thoughts? --Ckatz^chat_spy 21:12, 28 January 2010 (UTC)

Heaps better, so I put it in (with some slight modifications). Probably mostly due to my achy sleepy head I still see some problems with it though:

• It still just plain old doesn't sound good. If I was an author, and this sentence was trying to creep into my book... well, considering the standards of authors these days, I'd probably let it.
• It doesn't really fit either at the beginning of O&E or its current position.
• It goes on and on about Earth while ignoring all other objects orbiting the Sun. (OK, there are many very good reasons for that. To begin with, Earth is the only place we know of that has anyone concerned about apparent magnitudes on it. This therefore probably shouldn't be touched, unless you think however, due to its proximity, the Sun is the brightest object in the Earth sky usw. would work better.)

Now this is getting just petty... Perhaps I should get a life. Sideways713 (talk) 19:29, 29 January 2010 (UTC)

Matter/energy conversion (which happens) is NOT mass/energy conversion (which doesn't)

Matter is loosely defined, but often thought of as fermionic particles like electrons and quarks. Almost everyone, by contrast, agrees that photons and other guage bosons are not "matter." Using this definition, matter can be converted to non-matter, or energy in the form of photons (such as electron-positron annihilation producing two gamma photons). Also, kinetic energy can be converted to pairs of stable particles, as happens in accelerators.

Alas! This fact has caused some people to misunderstand E=mc² to think that MASS can be converted to energy in the same way. It can't. You can get rid of "matter" but not mass. Mass is not "converted". It is conserved, just like energy, because the two are the same thing, and neither appears without the other. Thus, matter is converted to light in the Sun, but MASS is not. The light has the same mass-- it's just mass moving away. One kind of energy is converted to another, and one kind of mass is converted to another. But both are separately conserved. There is no conversion for any given observer. Loss of either mass or energy only means they left the system and you didn't keep track.

Incidentally, even in the Sun, "matter" is not converted to energy in the sense of some "matter" as fermions disappearing and reappearing as photons. The "matter" destroyed in the sun is not atoms, baryons, or even fermions like quarks, but rather nuclear fields. It has mass, but that 4 million tons is not "real particles" (as field it is virtual pions or something). So although matter can be "converted" to energy, that's not what's happening in the Sun, either, unless you're talking about the part of "matter" which isn't identifiable real particles. So let us avoid the word "converted," unless to say that rest mass is "converted" to the mass of a system of moving massless particles (here photons). The mass and energy move from the Sun out into space, but that's all. The mass stays the same if you consider the whole system. SBHarris 02:03, 18 February 2010 (UTC)

I have two problems with your changes to avoid the word conversion: first, the source does not talk of an "equivalence rate", it talks of a "conversion rate"; second, the word conversion includes the concept of movement between two forms of a thing as in potential energy being converted to kinetic energy as a thing falls. I'm fine with dropping converted from the second sentence, but I think the phrase "carried away as energy" makes it clearer that the mass and energy are different forms of the same thing. "Carried away with (or worse, by) the energy" seemed to convey that the energy apeared out of nowhere and carried away the mass. The current "in the radiated energy" can be read both ways, I think, so I'm fine with your version. Celestra (talk) 03:38, 18 February 2010 (UTC)

Okay, good. The various types of energy can be converted to each other, and mass never changes during this, since obviously mass never appears without energy accompanying it, and vice versa. I would make the "mass in the energy" even stronger if I could. It's the mass OF the energy. Mass and energy are even more than different forms of the same thing (you make them sound like ice and liquid water). Even more, mass and energy always appear together. All energy HAS mass. All mass HAS energy. So it's not just that the mass is carried away AS light; rather the mass is a property of the light. The light has mass. First, this mass is in the Sun, THEN the mass moves off (leaving the sun lighter, but leaving whatever the light is absorbed by, heavier). It always stays mass. It always has a gravitational field, even after it is transformed to light. Mass is conserved over time, as seen by any single observer, period, end, full stop. YOu can't get rid of it, any more than you can get rid of energy.

Oh, and BTW, the source talking about "conversion" may simply be wrong. I think E = mc² is the most well-known equation in physics, and probably the most popularly misunderstood. You'll find endless sources that tell you it means mass can be converted to energy, and they're all wrong! A good physics text on special relativity like Taylor and Wheeler puts it straight.SBHarris 17:42, 18 February 2010 (UTC)

The entire heliosphere has shrunk?

I read at topic: Present anomalies

Its magnetic field is at less than half strength compared to the minimum of 22 years ago. The entire heliosphere, which fills the Solar System, has shrunk as a result, resulting in an increase in the level of cosmic radiation striking the Earth and its atmosphere.

There is no reference ... sounds a bit bold, I would suppose the heliosphere keeps on expanding as long as the sun keeps shining?Michel_sharp (talk) 21:42, 4 March 2010 (UTC)

Why cant I edit this page.

Why cant I edit this page?I logged in.Easterndarksunrise (talk) 02:39, 8 March 2010 (UTC)

This page is Semi-protected, so it can only be edited by users whose accounts are more than 4 days old and have 10 edits or more. --The High Fin Sperm Whale 02:44, 8 March 2010 (UTC)

Color of Sun description is bogus again (2010-03-08)

The second paragraph currently[1] says "and is informally designated a yellow star, because the majority of its radiation is in the yellow-green portion of the visible spectrum.[12]", where 12 is [2]. No. Well, "informally" is border line, because stellar classification isn't, and G class is often called "yellow". But definitely not "because the majority" (cite supports "majority" but not "because") - it's yellow relative to the blue spectroscopic reference star Vega (see stellar classification#Conventional_and_apparent_colors, currently[3] ok, though the table with colors above it has become variously bogus). The article is now semi-protected, so fyi. (The Sun is also yellow relative to the blue non-reference muppet Cookie Monster, but that isn't causal. And is blue relative to yellow Big Bird, purple relative to green frog Kermit, and green relative to purple dinosaur Barney.) 98.216.110.149 (talk) 20:12, 8 March 2010 (UTC)

Sun Conveyor Belt

This here is information, for which i'am not so sure if it's included in the article, at least check the image http://science.nasa.gov/headlines/y2010/12mar_conveyorbelt.htm There is also a link to the report on Science. ThorX 11:02, 15 March 2010 (UTC) —Preceding unsigned comment added by ThorX13 (talk • contribs)

Sun Core Temperature

The temperature at the core is listed as 15.7x10^6. Shouldn't this be written 1.57x10^7? Thanks. Rhcathal (talk) 11:13, 17 March 2010 (UTC)

Convective zone

Noticed while reviewing, that the density given for the top of the Convective zone (Photosphere) of 0.2 g/cm³ and the following parathetical statement(1/10000 of sea level density) didn't jive. These values are not equal. Checked reference (NASA1) and made minor correction.GeoPopID (talk) 13:46, 28 March 2010 (UTC)

Note that our unit is g/m³, which gives us the 6 extra zeros. Density of air is 1.2 kg/m³, which is (to 1 significant digit, and with a wince) 10000 times more. --Stephan Schulz (talk) 16:00, 28 March 2010 (UTC)

My mistake. Gram per cubic meter (g/m³) is a funny unit, and it got me! If I were God I would make the SI Committee change the name for the base unit of mass to something you can use the prefixes with. That would ameliorate a lot of these kind of errors.GeoPopID (talk) 19:18, 29 March 2010 (UTC)