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Milky Way redirect: Compromise part deux

Here's an option: move this article to Milky Way Galaxy and redirect Milky Way to that article. At the top of that article create a notice:

Milky Way redirects here. For other uses see Milky Way (disambiguation).

Then create a new article of the sort: Earth-based observations of the Milky Way or similar title for User:Halfblue to pipe the articles that deal solely with the band of light. Everybody wins.

Thoughts?

Nondistinguished 14:52, 14 September 2007 (UTC)

I think this is a strongly viable option which has good potential for consensus. I like it and it falls well within my range of acceptable outcomes. 67.166.145.20 14:55, 14 September 2007 (UTC)

Problem. This ignores reference. Reference states the the thing we see in the sky is called "Milky Way", not "Earth-based observations of the Milky Way". Also star ships have not been invented, till then there is only one viewpiont we see the Milky Way from ;^).

Dispite that title this is the old option that I still like. I propose we have this:

• point Milky Way to Milky Way (disambiguation).
• move content about the scientific thing (based on theory and its relevant observations) we call the Milky Way or The Galaxy to Milky Way Galaxy (please note: Milky Way Galaxy it a creation of modern science. It does not have mythology or poetry (well maybe some post 1920's poetry) or other cutural names. Those all belong in the Milky Way (celestial) page).
• create a page for the band of light in the sky at Milky Way (celestial).
• add links at Milky Way (disambiguation) to Milky Way (celestial) and Milky Way Galaxy.

Halfblue 15:14, 14 September 2007 (UTC)

I wouldn't say that this ignores reference... it still uses "Milky Way" appropriately in the title, just in a longer sentence. :) I completely agree with your point about mythology and poetry... I'd reached the exact same conclusion myself. Either title for the article on the band of light would be fine with me. 67.166.145.20 15:40, 14 September 2007 (UTC)

Why should Milky Way redirect to Milky Way Galaxy? Milky Way is the most common use of the term. I show around 40,000 hits in the scholarly literature for the term "Milky Way" that refers to the Galaxy, and less than 8,000 for "Milky Way Galaxy". And why would we create an article called Earth-based observations of the Milky Way when the only sources offered are interpretations of incredibly brief dicitonary entries? The current article can handle any sourced information concerning "Earth-based observations of the Milky Way", and if that content gets too big, then it can be split out into its own article. Of course, you could create Earth-based observations of the Milky Way without altering this article at all, but I don't see why. In any case, "Earth-based observations of the Milky Way" is a subset of the primary topic, "Milky Way" and doesn't change the status of this article in any way. —Viriditas | Talk 15:19, 14 September 2007 (UTC)

Please read reference above as to why a Google search is not a "reliable source". WP:V states quite clearly what is a "reliable source" is. Halfblue 15:29, 14 September 2007 (UTC)

But a google search can give a better indication as to useage of two different terms for an object than could a single dictionary entry, or a single 1981 textbook. Also, I provided a source which only references astronomical abstracts, 83 of the first 100 articles that came up had "Milky Way" in the title of the paper, 3 of the first 100 had "Milky Way Galaxy" in the title, and the remaining 14 had a title which didn't include either term. This gives us 83 references in favour of "Milky Way" being the name of the article, and 3 in favour of "Milky Way Galaxy". That's in addition to the 40,000 vs. 8,000 that the google search revealed. So to merely state that "Milky Way Galaxy" must be the only term allowed, is ignoring the references that we've both put forward. I agree with Viriditas, that any discussion of the "Earth based obs of the Milky Way" should be on the main article unless it begins to overwhelm the main article - but the galaxy aspect takes precidence. Richard B 15:43, 14 September 2007 (UTC)

See below re: consideration of scholarly sources vs. those aimed at the amatuer... and the sources are more numerous than you suggest, they just haven't all yet been fully and properly cited. There's an encyclopedic entry referenced by Nondistinguished which provides strong support for this convention of formal terminology, as well as what appears to be a professional-quality award-winning website aimed at the amatuer astronomer that I have linked to previously. These sources explicity declare that there is a formal distinction of terminology for the pedantic, and also acknowledge that the common usage is simply "Milky Way" for either. They tend to use the formal terminology consisently. I believe there appears to be sufficient applicable precedent for this convention to provide a strong case that a Wikipedia article should treat the subject similarly. 67.166.145.20 16:04, 14 September 2007 (UTC)

I'd be interested to see if this book follows a similar convention. The Wikipedia article on Pasachoff may also be worthy of consideration. He appears to be a noted author of astronomy books aimed at the target audience that I suggest we should address. 67.166.145.20 16:17, 14 September 2007 (UTC)

It is irrelevant whether or not there is a more formal name, since Wikipedia convention is to use the common (i.e. most recognizable) name for an object. When a single term, i.e. "Milky Way" can have more than one meaning, WP:DISAMBIG gives guidance about what should appear under that name. 76.231.189.193 16:14, 14 September 2007 (UTC)

I will consult those guidelines more carefully, but from my understanding, the conventions aren't inconsistent with the conventions I propose. More experienced Wikipedians have made similar statements. I'll definitely review the guidelines closely, though, and bring back a more thoroughly reasoned analysis of my interpretation of them. If they convince me that the proposal is in substantial violation of the established guidelines, I'll moderate my position accordingly. 67.166.145.20 16:21, 14 September 2007 (UTC)

I don't see anything there that shows compelling reason not to seriously consider this change, and debate its merits thoroughly. The advisory at the top of the page notes that these are guidelines, not written in stone, and the occasional exception should be allowed if circumstances warrant. Furthermore, it's not clear to me that the proposal under consideration would be an exception to those guidelines. It appears consistent with them to me. If the argument is that the most common usage of the term "Milky Way" is to refer to the galaxy and not the visual spectacle, I submit that this opinion may be context-dependent. It appears there are many among the amatuer astronomy community who consider that the band of light is the most common meaning of the term "Milky Way" when used alone, and the evidence that this terminology is taught as fact in undergraduate-level textbooks, and presented as such on professional websites devoted to amatuer astronomers and in major encyclopedic references, appears to often cause considerable misunderstandings between such astonomy buffs and those who have no professional reason to distinguish between the topics at all. It is a prominent visible feature of the night sky, of interest to stargazers, and this feature is not the same physical object as the galaxy, just as the sun is not the same physcial object as the solar system. Other prominent night sky features have articles for this audience, most notably articles on the constellations and common asterisms. I feel a similar treatment of this striking visual phenomenon, which is distinct from the Milky Way Galaxy itself, is well-deserved. 67.166.145.20 17:30, 14 September 2007 (UTC)

Let's not pretend that the Milky Way is the same as the Solar System here. The Sun would be equivalent to the central bulge of the galaxy. We can see the rest of the solar system as point-like objects - the planets, asteroids etc. The vast majority of rest of the galaxy can be seen as a hazy band of unresolved stars - although much is obscured by dust lanes. We have an article about the solar system - and we have an article about a lot of the components of the solar system - as we do for many of the nearby stars in the galaxy. Richard B 18:08, 14 September 2007 (UTC)

Just so you know, I'm not pretending, I'm stating an analogy that I believe has logical merit. Fair enough? :) My basis for this analogy includes the following: Most of the light we see in the solar system comes from the sun, and most of the light we see in the galaxy comes from the stars that comprise the Milky Way visual phenomenon. The sun comprises the vast majority of the mass of the solar system, and the stars that are contained within the hazy band of light we see comprise the the vast majority of the mass in the galaxy. The solar system includes components resolvable from earth that are not part of the sun, and the galaxy includes components resolvable from earth that are not part of the hazy band of light. From a distant frame of reference there is no significant gravitational difference between the sun and the solar system, and from a distant frame of referenc there is no significant gravitational difference between the stars visible as a hazy band of light and the galaxy as a whole. Based on these and other comparisons, I suggest that to equate the hazy band of light to be the same physical object as the galaxy is the functional equivalent, in the context of the proposed disambiguation, as to equate the sun to the solar system. I feel confident that this logic is iron-clad. Please feel free to attempt to show me that it can be refuted; I welcome the debate. 67.166.145.20 18:23, 14 September 2007 (UTC)

OK, Most of the light we see in the solar system does indeed come from the Sun - and the vast majority of the mass is from the Sun. No problems with that so far. There are many components resolvable from Earth - e.g. the planets, in the solar system but not within the Sun. Again, no issue with that. From a distant vantage-point, you'd only see the Sun. But Wikipedia generally only has a single article about other distant star systems with multiple components, even if those components are stars themselves - e.g. Capella is a 4-star system, but 1 article.

Now onto the galaxy. From our vantage-point on Earth, the vast majority of light from the galaxy comes from...the Sun. It's about 14 billion times brighter than the next brightest star, Sirius, which in turn is at least 2000 times brighter than stars at the limit of human vision. The vast majority of stars in the Milky Way appear *much* fainter than that. For instance, Proxima Centauri - the closest star to the Sun would be 3 trillion times fainter than Sirius if it were placed near the centre of the galaxy. From a distance, however, and we'd just see the galaxy. The majority of light coming from spiral arms, O-B associations, the galactic bulge most likely. We can't see all of them from Earth. Also, gravitationally, most of the mass in the galaxy is in stuff we can't even see. And we can't even see it from a distant viewpoint either. Note also that we have plenty of articles about components of the galaxy - Sun, Sirius, Deneb, Messier 42 ad nauseam, just like we have articles about components of the Solar System - Jupiter, [[ - but the band of light is simply the view of the visible extent of the galaxy itself. It isn't really a component - and it isn't resolvable - that's why it's a hazy band - it's more of a density distribution that we can see. Richard B 22:30, 14 September 2007 (UTC)

Fair enough. I concede the accuracy of the technical corrections, I was approximating to my best knowledge. Not sure how I feel that impacts my core argument... I'll sleep on that one. But just so you know, the most important/interesting reason I think the analogy is relevant is because in each case, the distinction between the two vanishes in some contexts but becomes clear in others, and I suggest that to judge one context as substantially more important than the other, and more worthy of inclusion as a separate article, seems to me like a value judgment as to the significance or insignificance of a particular frame of reference. This seems unfair, and not necessarily in line with what I understand to be Wikipedia best practices. Feel free to respond with further reasoning, but I probably won't have a chance to get back to you for a while. 67.166.145.20 22:44, 14 September 2007 (UTC)

Scholarly literature may be a less appropriate source to consult than literature aimed at the amatuer astronomer and undergraduate level students. I submit that these sources more often disambiguate the two terms, and when they do, they do so consistently as we have maintained. For the purposes of a brief acknowledgement of the formal terminology when aimed at those audiences, I believe these sources carry more weight. I would think that the reason scholarly papers disambiguate less often is because scholars are more likely to know which meaning is intended by context, and not get confused. 67.166.145.20 15:36, 14 September 2007 (UTC)

P.S... this may give insight into my core claim. It's a pretty good statement of it in different terms from before. I submit that since this convention is used fairly consistently in such sources, including encyclopedia articles, there is a strong case that these are appropriate to consider when considering full article titles here. 67.166.145.20 15:54, 14 September 2007 (UTC)

I see no reason not to go ahead and declare that, if we do end up moving the article, the best title to move it to would be Milky Way Galaxy. That can complete the official documentation of the proposal that the page be moved, with the clear understanding that this proposal will be hotly contested and that if consensus is not reached, the move will not occur. Is there objection to formal submission of the title "Milky Way Galaxy" as the destination we would like to move it to, if it ends up moving? No rush, but if there's no reason to wait, we might as well. 67.166.145.20 20:20, 14 September 2007 (UTC)

Scholarly, academic, government, and amateur literature all predominantly refer to the "Galaxy" as the "Milky Way". I don't see any evidence that this page title should be changed, moved or altered; I see just the opposite. All of the available evidence shows that the article resides at the most common name, with a dab header at the top for other uses. I also don't see how changing the name of this article will improve Wikipedia's coverage of the topic. It's one thing to quote dictionary definitions, 1981 textbooks, and websites, but at the end of the day, the most current research and publications are the most relevant sources for determining usage. Now, we can all agree that many of these sources state that the term "Milky Way" does indeed, have two meanings: the band of milky-white light we see in the sky, and; the barred-spiral galaxy we call home. The former use of the term is generally used in the context of history and etymology, referring to the astronomical object we see with the naked eye from Earth; while the latter is used to refer to the Galaxy. We can all agree that on a dark night, the band of light seen stretching across the sky can be referred to as the Milky Way without necessarily talking about the Galaxy itself; after all, the name of the Galaxy derives its designation from this term, and it was used long before the mysteries of the Galaxy were partially revealed. And in the context of amateur astronomy, we can see that this name is still used, not to refer to the Galaxy in particular, but to the "grouping of stars, dust, and gas in our own galaxy". It is perfectly reasonable for the present article to include more information about this topic, and if that content grows to a point where it requires a new article, then we will split it off. I would suggest that anyone interested in writing about the "hazy band of gas and light" as seen from Earth, expand the current article with enough relevant text to justify creating a new one. —Viriditas | Talk 20:49, 14 September 2007 (UTC)

That seems reasonable to me. Your points are well stated as to what we can all agree on, and I thank you, very much, for taking the time to figure out just what these "weird" propositions and claims to verifiability were about. I'm not yet ready to concede that there isn't necessarily reason to move it if that's where consensus goes. I suggest that given the fact that, as you concede, many of these sources state that the term "Milky Way" does indeed have two meanings, some concession to that be made in the text of the article, as a nod to the fact that this precedence of language does exist and is used by some. I suggest that in the lead to the article, and perhaps in any existing or forthcoming content that pertains more to the nature of the "hazy band of gas and light", some effort be made to distinguish between the two concepts, while in the more techinical parts of the article, the use of "Milky Way" as a shorthand seems fine. I think that it should be regarded as a no-no to use the term "the galaxy" in cases where what is clearly meant by context is unambiguously the "hazy band of gas and light". How fair do these suggestions sound, individually and/or as a group? 67.166.145.20 21:07, 14 September 2007 (UTC)

My problem is with insisting on a technical distinction in the lede. Previously, Halfblue (and possibly others) added the following to the lede: The Milky Way, when observed from Earth's surface, is the hazy band of white light that is seen in the night sky, arching across the entire celestial sphere. It is composed of stars and other material lying within the galactic plane of our galaxy, the Milky Way Galaxy. The word galaxy (from the Ancient Greek γαλαξίας) means "milky". I don't have any issues with that material. This material, however, has some problems: Technically speaking, the term "Milky Way" alone should refer exclusively to the band of light in the night sky, while the term Milky Way Galaxy (or "the Galaxy") is the proper description for our galaxy. In practice, however, the intended meaning of the term is often clear from the context in which it is used, and the term "Milky Way" is routinely used to refer to either topic. I'm not sure the distinction is necessary or helpful. I would rather see more information about the historical use of the term and its use in amateur astronomy. I haven't seen any sources that insist on this technical distinction, although I admit that it makes sense. We're really not supposed to tell people how to use words per WP:NOT. —Viriditas | Talk 21:20, 14 September 2007 (UTC)

Fair enough. The earlier opening you cite is something I found to be an acceptable level of acknowlegement of the convention, right in the first sentence. The one you object to was my clumsy but developing attempt to help put forward the part of the claim to verifiability that might make sense, in an effort to stave off uncontrollable edit war. I have no objection to jettisoning that particular formation of the proposed distinction, if the article opens in the balanced way you cite. If and when a split happens, of course, different conventions may be decided upon for the other article. 67.166.145.20 21:46, 14 September 2007 (UTC)

Most of the previous opening material already appears in the second paragraph of the current lede. How would you change the current lede to your satisfaction? It appears natural and appropriate to refer to the Galaxy in the first paragraph, leaving the description of the term to the second paragraph, although I have no objection to improving the lede. Do you think that adding the "hazy band of white light" to the first paragraph is better than what we have now? I have no strong opinion on this matter, but I suggest that we think of the reader. If you feel a calling to rewrite the lead, by all means do just that, but please keep the Galaxy in mind as the primary topic. —Viriditas | Talk 22:04, 14 September 2007 (UTC)

I think that the article should open straight off with the precise first passage you quoted, that you say is acceptable, in the place of the current first sentence or two, with the first instances of each of the terms "Milky Way" and "Milky Way Galaxy" in bold. I can do that specific change, although I don't have the remaining energy today to improve the flow of the rest of the intro to match, as far as overall flow is concerned. Shall I alter the opening paragraph as I describe and leave it to others to pretty it up? If so, any preference as to whether I replace just the first sentence, or the first two sentences, with the quoted passage? If you'd rather the entire set of any modifications to the lead section be done as a piece, for flow, I think/hope I've articulated my proposal well enough to check in tomorrow and see if it meets with my approval. 67.166.145.20 22:21, 14 September 2007 (UTC)

I've decided to go ahead and take a pass at it, and make some effort to show what I think is an acceptable level of compromise. My greatest concern is the first sentence, which I think I can phrase in a way that most should find acceptable, based on what you've told me... I'll make a few other minor disambiguation-of-terminology edits and try to make sure information isn't repeated unneccesarily or lost, with the understanding that some cleanup/rearrangement/stylistic choices will probably need to be tweaked with. I think the first sentence is what's most important to ensure that the stated disambiguity concerns are met. I'll do that, then crash. 67.166.145.20 23:04, 14 September 2007 (UTC)

Done. I think the text of the first two sentences should be left as is for now. My other changes are just my opinion of what flows best and is pretty consistent with textbook terminology. Later. 67.166.145.20 23:18, 14 September 2007 (UTC)

Some mods made to the intro re: WP:LEAD and redundancy.

Re: using Google to find a correct usage of a term. If you search "America Under Attack" you get 85,900 hits[1]. If you search "United States Under Attack" you get 4,100 hits[2]. That is the pitfall of trying to use Google searches to define a term. People use shorthand like "America" when they actualy mean "United States". You just can't use a Google search to define a term (and did I say its Original Research?)

Re:Two articles describing the same thing? We have example such as Aurora (astronomy) / St. Elmo's fire / Plasma... Rainbow / Refraction. Halfblue 03:30, 15 September 2007 (UTC)

Halfblue, several editors (including myself) have previously addressed your concerns about Google searches. Again, the links to Google search results concerning "Milky Way" are not links to web searches as you have offered above; they are links to restricted searches of books and scholarly papers. —Viriditas | Talk 07:56, 15 September 2007 (UTC)

Viriditas, is does not matter where you search. It is how you search that is the problem. And no such search supercedes reliable sources. A search can olny find more reliable sources. Reliable sources are pretty clear at this point. Halfblue 13:01, 15 September 2007 (UTC)

I've already provided the Wikipedia links above explaining how searches are used to determine usage, notability, and article names. I'm not sure how much more help can I offer you. —Viriditas | Talk 05:16, 16 September 2007 (UTC)

Furthmore: A raw Google Scholar search gives us 40,800 hits for the title "milky way" and 118,000 for "the Galaxy". By that resault the problem is solved, we have a second article called "The Galaxy" Halfblue 13:19, 15 September 2007 (UTC)

I'm sorry, but that doesn't make any sense. There is no evidence that the term "the Galaxy" refers to the "Milky Way" in every instance that you refer to; it may well refer to different galaxies. On the other hand, the term "Milky Way" refers to "the Galaxy" when used in that context. I hope that clears things up. —Viriditas | Talk 07:21, 16 September 2007 (UTC)

Okay. I've slept on it, and I have some new ideas and positions. I will attempt to improve my ability to present them in an organized and concise manner. It will take some time for me to do so. I ask for patience.

I believe that the current presentation of the article represents the closest thing we have to a stable consensus right now. It's not perfect, but it's a start. Improvements are possible that can address the concerns of all parties.

I'll formally present my ideas soon, once I am confident I can do so in a competent fashion. 67.166.145.20 12:39, 15 September 2007 (UTC)

Please consult with WikiProject Astronomy. You are invited to present your ideas here. —Viriditas | Talk 05:31, 16 September 2007 (UTC)

Thank you for the link. I will check it out and attempt to present my ideas there when I feel ready/competent to do so. 67.166.145.20 09:54, 16 September 2007 (UTC)

Down to basics

I recognize that my inexperience has resulted in some difficulties of presentation and appropriateness of content to this talk page. However, my contributions have been made in light of the two following priorities, which I think we can all agree on:

• A stable, accurate, high-quality article
• A civil, productive discussion about how to achieve that end

I found the previous state of affairs highly unsatisfactory on both levels, felt positioned to act, and felt obligated to do so despite my inexperience. If that choice has offended anyone, I apologize.

To the matter at hand:

I feel some tension has been resolved by the acknowledgement that there does exist, in some relevant contexts, cause to disambiguate between the Galaxy and its visual characteristics. Some positive initial action has been taken to address this, and that's good.

For clarity of discussion here, I suggest that we take care to make clear what definition of the term "Milky Way" we are talking about at any given time so that everyone can understand what we mean. To that end, I suggest that we avoid usage of the term "Milky Way" in isolation, as that term means different things to different people. If we mean the Galaxy, we should say the Galaxy. If we mean its visual characteristics, we should refer to them as its visual characteristics. It is my judgment that these terms will be the least volatile and most clear.

On reflection, I have concluded the following:

• We should defer to those who have put time and energy into this article on whether the amount of content warrants a split into a second article. I have some ideas for additional content to work toward that eventual goal, and present a more balanced but accurate article, in the tradition of scientific accuracy that reflects the article's current focus.

• As is, this article is about The Galaxy and its Visual Characteristics. Taken together, these topics are the primary meaning of the term "Milky Way." Considered separately, its not clear to me that there is a primary topic, but if there is one, I think it's probably the Galaxy. With this in mind, it is clear that the link to "Milky Way" should point to this article, in its current form.

• The primary focus of this article, however, is currently on the Galaxy. As such, "Milky Way Galaxy" may be a more appropriate article title. As long as the link to "Milky Way" redirects to this article, it seems to me that the only effect of this change will be the article's title. I believe there may be cause to do so at this time, and feel this option warrants further discussion, as long as we can keep such discussion civil and productive.

That's where I stand. Thoughts? 67.166.145.20 15:11, 15 September 2007 (UTC)

These issues have already been addressed in previous discussions above and there is no reason to move the article as it currently resides at the most common name. I see that you and another user have recently added "Galaxy" to the occurrence of every use of the term "Milky Way" in this article. Not only isn't that necessary, but it's not how the term is used in the academic literature, and when it is used, it often appears lower case and it is usually only used once to introduce the subject and is dropped subsequently. I'm going to remove the repeated use of this term from the article. —Viriditas | Talk 05:20, 16 September 2007 (UTC)

I agree that the full name was overused. Some level of balance should be strived for in that, for purposes of flow and readability. I appreciate your reasons for these edits.

RE: your restoration of the parenthetical clause I had removed. I agree that the word "Galaxy" is derived from "Milky Circle", and that this is directly relevant to this article. However, I contend while it is sometimes (often) permissible/acceptable/advisable to use the shortened term "Milky Way" to refer to the Galaxy, the term "Galaxy" should not be used to refer to the visual characteristics alone, and it seems clear to me that the term "Milky Way" is used in the context of these visual characteristics in the opening sentence. A solution to this dilemma must be found. 67.166.145.20 09:50, 16 September 2007 (UTC)

I am familiarizing myself with the improved versions of WP:NPOV, WP:V, and WP:NOR. These articles are much easier for me to follow in their present form, and I believe I perceive a solution that more accurately represents the state and level of controversy, and reflects these essential guidelines. I ask a little more time to formulate it completely and properly; I'm new at this, and I want to make sure to get this right. I think I can provide a revision to the lead that will be superior to the current version for all concerned. 67.166.145.20 12:42, 16 September 2007 (UTC)

I've added a template to the page which I believe is a better way to represent the lack of consensus than a proposal to change the name. Although I still think such a move would be a good idea, I now realize, based on my increased understanding of the relevant policies, that such a move is probably premature at this particular time. I am willing to abandon the proposal to move the page for the moment, but I am not opposed to such proposals and realize they may be reopened by others. 67.166.145.20 13:18, 16 September 2007 (UTC)

The final paragraph represents the exact claim I have clumsily tried to argue for. My only additional claim is that in light of this, and in light of simple logic, "The Galaxy" should not be used when the intended context clearly refers exclusively to the visual phenomenon. Full post-mortem to follow, for future instructional purposes as to how such polarized conflicts can be avoided. After that, my work here is done. 67.166.145.20 15:56, 16 September 2007 (UTC)

Post-Mortem

There have been a lot of errors of miscommunication over the past days, some of them mine. My primary fallacy has been to argue what I see as Halfblue's verifiable claim regarding terminology, using that same terminology. I have a tendency to exclusively prefer an explicit, formal definition over a more generalized, commonly used definition, and I suspect Halfblue may share this tendency. This may or may not be consistent with Wikipedia naming conventions; I lack sufficient understanding of these conventions to be sure. My additional fallacy was to adopt this personal preference for explicitly stated definitions over commonly held definitions as a fundamental truth about "proper terminology"; this is my own bias which has now been revealed to me. As a result, the following comedy of errors occurred:

From my perspective: Halfblue and I would say: "Look, the galaxy itself is not precisely the same object as its visible characteristics when viewed from Earth!" To which others would respond, "That's ridiculous; they are the exact same thing. The galaxy's visual appearance from Earth is exactly equivalent to the galaxy itself." We would reject this notion as trivially false, and the debate would go round and round.

From my improved understanding of the opposed perspective: Halfblue and I would state, "The Milky Way is not an acceptable term with which to refer to the galaxy!" to which the natural reply would be "Of course it is!! It's the most commonly used term to refer to the galaxy!!" Our seemingly outlandish claim would be rejected as trivially false, and the debate would go round and round.

My passionate attempts to clear up this misunderstanding originated from my extreme distaste for A) the severe instablility of the article, B) the poor quality that resulted from this instability, and C) the highly unpleasant atmosphere on the talk page. I was not fully aware, due to my own blind spot in this matter, that my efforts to clear up this misunderstanding might have contributed to precisely the unpleasant atmosphere which I was committed to dispel. I attributed any personal contribution I might have made to this unpleasant atmosphere to my inability to accurately communicate what I meant, to which I would respond by trying harder.

My efforts were also motivated by an attempt to shed light on what I perceive as a systemic bias held by some in this community. My passion for this cause was similarly fueled by my commitment to resolve miscommunications.

These personal biases, tendencies, and passions I possess are largely due to the fact that I happen to have Asperger's Syndrome. People with this type of neurology tend to experience great difficulties with practical interpersonal communication, and often experience substantial frustration as a result, on a continuing basis. I mention this not to be inappropriately personal, nor to excuse my own genuine mistakes, nor to seek any kind of sympathy (I accept my condition as a natural part of who I am, and often perceive such expressions of sympathy as unwarranted and unwelcome) , but merely to illustrate my belief that sometimes, a person's perceived stubbornness may have causes that are not immediately obvious, and oversimplification of such behavior as "willful refusal to understand" can often be harmful to oneself and others.

I have found this entire experience to be highly challenging, deeply rewarding, and intensely positive. To those who have had a dissimilar experience of these events, I offer my sincerest apologies for my part in that. To each and every person who has engaged with me in this discussion, I offer my deepest thanks, from the bottom of my heart, for the chance to challenge myself in this way and improve my ability to communicate clearly. I have strengthened and grown as a person as a result. Words cannot adequately describe how sincere I am in these statements.

We now return you to your regularly scheduled Wikipedia. 67.166.145.20 17:42, 16 September 2007 (UTC)

Naming conventions

It seems to me that moving this article to Milky Way Galaxy shouldn't be that controversial. True, many people drop the "Galaxy" as redundant, but many also do the same with Andromeda Galaxy. I don't think we need to resolve at this time whether there should be a separate article for the band of light. We can probably get away with pipe-linking to the appropriate section within the main article until such a time as there is too much content and a fork should be initiated. Thoughts? Nondistinguished 20:42, 16 September 2007 (UTC)

But why bother doing that? The common name approach would suggest "Milky Way" is the appropriate title. You can't drop the "Galaxy" from "Andromeda Galaxy", because Andromeda is a constellation - the galaxy is named after where it is in the sky. And I would also suspect "common name" useage to give "Andromeda Galaxy". "Milky Way Galaxy" already redirects to "Milky Way", so there's no real point in moving. Richard B 22:36, 16 September 2007 (UTC)

The common name approach does not superceed reliable sources. Those sources already give us the name of the band of light in the sky "Milky Way", and the name of the Galaxy "Milky Way Gallaxy" or simply "The Galaxy". Not only can you "not drop the "Galaxy" from "Andromeda Galaxy", because Andromeda is a constellation", you can you not drop the "Galaxy" from "Milky Way", because "Milky Way" is a band of light in the sky. Halfblue 12:14, 17 September 2007 (UTC)

The common name does actually superceed the technically correct name for article titles. As has been pointed out to you several times, the two are the same thing - the band of light is just the Milky Way as viewed from Earth. It's effectively a density distribution of unresolved stars, largely in the spiral arms and galactic bulge. As others have pointed out, the half-degree-wide circle of light that you see during the daytime when it's not cloudy is the Sun. It's a star which appears to us on Earth as a bright disc. We don't (and rightly so) have articles on the visual phenomenon of the bright disc. Richard B 13:02, 17 September 2007 (UTC)

The problem is your not following through with even identifying the common name. "Search engines are sophisticated research tools, but often have bias and results need to be interpreted. It can be worked round but you need to know what you're doing" (Wikipedia:Search engine test). If you search "Milky Way" in Google Scholar" you have to then interpret what the author meant in those titles. If you asked every one of those authors "Do you mean within the confines of the band of light" they would say "no, I mean "The Milky Way Galaxy" "Hit count numbers alone can only rarely "prove" anything about notability, without further discussion of the type of hits, what's been searched for, how it was searched, and what interpetation to give the results. On the other hand, examining the types of hit arising (or their lack) often does provide useful information related to notability" Halfblue 13:55, 17 September 2007 (UTC)

We have discussed this several times. The majority of publications use the term "Milky Way" to refer to the galaxy. When relying upon sources, we make sure we use the most authoritative and current ones. A single textbook from 1981 does not suffice, nor could it. And, a personal website does not meet our requirements. —Viriditas | Talk 15:24, 17 September 2007 (UTC)

I think that the reason for moving to Milky Way Galaxy might be best understood by considering the naming conventions listed for galaxies. Wikipedia:Naming conventions (astronomical objects)#Galaxies. I understand that some may consider the Milky Way to be a special case, but I think that it is better in terms of being particular to make sure people understand that it is a galaxy in the name. Nondistinguished 13:31, 17 September 2007 (UTC)

People understand it just fine. "Milky Way" is the very translation of "Galaxy". There's no need to call the article "Galaxy Galaxy". —Viriditas | Talk 15:20, 17 September 2007 (UTC)

"Milky Way" is the translation of "Via Galactica". There is no translation of "Galaxy". Nondistinguished 17:19, 17 September 2007 (UTC)

I'm referring to Ptolemy's use of galaktikos kyklos, which is close enough for my purposes. —Viriditas | Talk 17:32, 17 September 2007 (UTC)

Many readers at Wikipedia probably will not know that the term "galaxy" is derived from the Milky Way. It's not exactly common knowledge. Nondistinguished 19:53, 17 September 2007 (UTC)

Recent changes

By reference we should either have an article that is:

• A) A one topic two description article where we describe the Milky Way as seen in the night sky and follow on to describe the Galaxy (as supported by the eSky source and The Cambridge Encyclopidia Of Astronomy)

or

• B) Two articles for each thing where we disambiguate link to them (supported by Contemporary Astronomy / Jay M. Pasachoff and the OED).

I have made edits that follow the first course (and consensus). A split and disabigulation of the article may still be a prefereable course of action Halfblue 14:15, 17 September 2007 (UTC)

I have reverted your changes. Please take your concerns to the WikiProject Astronomy talk page linked above. "eSky" is a personal website; Pasachoff's textbook is from 1981 (!) and the convention he follows is not subscribed to by most textbooks. I don't know what edition of the Cambridge Encyclopidia of Astronomy you are quoting, but the 1999 Cambridge Concise History of Astronomy does not use the convention you refer to above, nor does the 2007 Encyclopedia of the Solar System, nor do thousands of scholarly papers published within the last seven years.[3]. —Viriditas | Talk 15:59, 17 September 2007 (UTC)

In the interests of collaboration, I'm going to revert back to your version in good faith to see how others deal with it, even though I am opposed to it. —Viriditas | Talk 16:17, 17 September 2007 (UTC)

I disagree with Halfblue's actions too. The primary description should be of the galaxy and not of the Milky Way as seen in the night sky. Nondistinguished 17:20, 17 September 2007 (UTC)

I have reverted back to a previous version. We need to start from the better version if we are going to get anywhere. I thought we'd already resolved this. Nondistinguished 17:24, 17 September 2007 (UTC)

Option A) above is not a resolved consensus. Looking at the request for comments above, there are several comments that agree with A and several comments that say that the galaxy is the important part of the subject, and should come first. Personally, I don't care what section comes first, but the lead must have a good summary of all of the important issues about the galaxy we live in. The galaxy-focused lead that integrates information about the observation of and the physical characteristics of the galaxy is far preferable to the various truncated leads. However, the 4th paragraph in the current version [4] needs to go. A detailed discussion of usage (which that paragraph is not) belongs in a section of the article, not in its lead.

Also, User:Halfblue, you can't say that a certain source supports separate articles or a single article. How many articles a subject needs to cover it is a function of how much information there is on Wikipedia about it, and this is expected to change with time. There are families of organisms with common articles and no species articles, and tons of articles about specific species. There is not one correct answer to how much should be covered in an article. An article's scope is contingent on how much information has been written on wikipedia and the best way to organize that information. Enuja (talk) 18:32, 17 September 2007 (UTC)

What about moving the fourth paragraph to a footnote? This follows how the Solar System article deals with the issue of capitalization of the term "Solar System". I tried to do so myself but encountered technical difficulties. 67.166.145.20 14:47, 18 September 2007 (UTC)

Also... I disagree with A), with the article as it currently stands. Most of the content of the article is currently about the galaxy and the lead should reflect that, unless/until the article is expanded to the point where the physical galaxy is no longer the primary topic. I don't know that that would ever happen. It does need more balance, though... as is, the structure doesn't seem to reflect the new and improved version of WP:NPOV. Perhaps merging the Milky Way (mythology) article back into this one would address this. As has been noted, any mythology is about the band of light, not the galaxy. That's just one suggestion I'm throwing out there, though, and I'm not attached to it. I encourage all editors to revisit WP:NPOV and review it carefully; it seems to me that this policy has been rewritten substantially, and it seems more clear now how it applies to this current situation. 67.166.145.20 14:58, 18 September 2007 (UTC)

Just wanted to let people know that I spent the day researching this matter on the UC Davis campus. I hit the bookstore, the main library, and the physics and engineering library. I have four additional sources to support this convention of terminology, all superior to what's been provided so far. One brand new textbook for this year's class, one textbook from the mid-90's, the 1998 Encyclopedia Britannica, and the 2000 Petersen Field Guide to the Stars and Planets. It'll take some time to type up and present the information. From 2 of those sources I have just the explicit definition as laid out in the texts; from the other 2, I have that plus every other usage of the terms "Milky Way" or "Milky Way Galaxy" in the texts. It all strongly supports this convention of terminology. I'm not sure how much people want, but I wanted to be on the safe side and get as much as I could. It'll be a while before I have the full citation details properly organized and prepared; that part is very difficult for me. I'll work on that and then check back to see whether people just want the definitions from each source, or all the bells and whistles. Back in a while. 67.166.145.20 22:51, 18 September 2007 (UTC)

But is this convention actually used? From looking at the astronomical literature, it appears the answer is no. It's also the opinion of a select group of authors, rather than a standard embraced by the entire astronomical community. —Viriditas | Talk 04:44, 19 September 2007 (UTC)

To me, the level of widespread usage of the convention is orthogonal to the possible general acceptance of the existence of the convention. Even Pasachoff, once in thirteen relevant passages in the field guide (by my count), does find occasion to use the shortened "Milky Way" to refer to the galaxy. Specifically, on p. 171 of the field guide: "The Milky Way is only one of millions of galaxies in the universe."

This seems to me to illustrate an important point. I don't perceive that anyone has claimed that it is unacceptable to use the short term "Milky Way" to refer to the galaxy. It is often convenient to use the short term in that context, and it's common practice. Even many of the sources that explicitly explain the difference acknowledge, in the next sentence, that the short term is commonly used in either case. I don't perceive that as being in dispute. To me it seems clear that the convention exists, and that many who don't formally use it in academic practice might still readily acknowledge its existence if questioned, and acknowledge that there is a convention. It also seems clear that although it should be an acceptable editorial choice to refer to the galaxy as simply "The Milky Way", it should not be an acceptable editorial choice to refer to the visual phenomenon as "the galaxy." My judgment is that this is a convention used by a significant minority, per WP:NPOV, and that Jay Pasachoff qualifies as a "prominent adherent."

I also find it notable that those who adhere to this convention are those who author works intended for an audience that may have no initial familiarity with the concepts. As Wikipedia is intended for a wide audience, and not merely the well-informed or highly-educated, this seems significant. 67.166.145.20 13:24, 19 September 2007 (UTC)

On Nomenclature

When a college level text book states: "Don’t be confused by terminology: the Milky Way itself is a band of light that we can see from the Earth, and the Milky Way Galaxy is composed of a hundred billion stars plus many different types of gas, dust, planets, etc. The Milky Way is that part of the Milky Way Galaxy that we can see with the naked eye in our night time sky". -- (Contemporary Astronomy - Second Edition, by Jay M. Pasachoff, P.414), that is a statement of nomenclature. Nomenclature, if it is established, is not to be ignored or discounted. Scientific Nomenclature is a primary way of determining articles titles and subjects (Wikipedia:Naming conflict). Any claims that nomenclature has changed need to be supported by reference. Nomenclature is not established via Googling (unless you come across articles that specifically deal with nomenclature). On line sources seem to be following this nomenclature, differentiating between one "thing", Milky Way, and a second "thing", Milky Way Galaxy [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] (please also refer to Talk:Milky Way#Additional Sources). Searches on Google Scholar are currently being used in a biased non-neutral interpretation (something that should be specifically avoided re:Wikipedia:Search engine test#Search engine tests and Wikipedia policies ---> Neutrality). The bias comes from failure to properly intemperate the results (in fact no interpretation is being used at all, the editors are simply doing a word count, counter to Wikipedia:Search engine test#Search engine tests and Wikipedia policies ---> Notability). This brings in a bias along the following lines:

• Failures to consider skew caused by what field of studies publish papers – astrophysics and cosmology are very large fields. Observational astronomy is not a scholarly pursuit and is practically non-existent as any kind of discipline; therefore very few papers about the visual phenomenon “Milky Way” will exist.
• Failure to consider how titles are worded. When you see an overwhelming number of papers titled "New York"[15] that refer to the city it is wrong to assume that New York State has ceased to exist as an entity. (BTW, New York City and New York is a good example of two articles that describe a thing and a portion of a thing that share the same name).

So far the opinions expressed by editors above are just that, opinions, and not a basis for creating or structuring an article re: WP:V and WP:NPOV. Actual reference have to be cited, not opinion. The International Astronomical Union may be a definitive source on this but I can't find a reference. Sky feature nomenclature may fall outside their bailiwick of naming radiating and non-radiating bodies, (also Pluto might have them rattled ;^)) Halfblue 16:11, 19 September 2007 (UTC)

And references to scientists using "Milky Way" to mean the galaxy in their professional work shouldn't be ignored either. At best, what has been shown is that people who choose to draw a naming distinction between the band of light and the galaxy often do so by differentiating between the terms "Milky Way Galaxy" and "Milky Way". However, that isn't the same as demonstrating that the others who refer to the galaxy as the "Milky Way" are wrong (and the latter usage may even be more common). If this article is going to describe both entities, it also doesn't strongly bear on the structure of the presentation. I would still argue that the galaxy is the more significant term and thus in a combined article deserves the focus. 76.231.189.193 16:43, 19 September 2007 (UTC)

I agree with just about all of this. I think the impact on structure of presentation is non-negligible, but that appears to me to have been satisfactorily addressed by the recent edits by Jengod. I hope it's clear that it was never my intent to claim that those who refer to the galaxy as the "Milky Way" are wrong. I have not and do not agree with any such claim. 67.166.145.20 17:39, 19 September 2007 (UTC)

I can find plenty of recently published, observational astronomy books that use the term "Milky Way" to refer to the Galaxy, such as Springer's Astronomy of the Milky Way (2004) by Mike Inglis and Cambridge University Press's Observing the Universe: A Guide to Observational Astronomy and Planetary Science (2004) by W. Alan Cooper and Andrew Norton. Then there are books that use both conventions to represent the galaxy, such as Cambridge University Press's Observational Astronomy (2006) by Birney et al. —Viriditas | Talk 19:47, 19 September 2007 (UTC)

Yep. Lots of sources call the galaxy simply "Milky Way," or only use the full "Milky Way Galaxy" intermittently. No argument there. To me, this seems most likely to be simply a matter of editorial choice on the part of those authors, and not a refutation of the formal nomenclature. It's widely accepted practice to use the simple term "Milky Way" in either context. This doesn't mean that the more formal nomenclature is no longer valid, merely that many don't find it necessary to use it in practice. As was pointed out above, it's like just saying "New York" when you mean "New York City", because it's expected that people will know what you mean. But really, it could mean either "New York City" or "New York State", and there's a convention of nomenclature to distinguish between them when ambiguity is possible. That's all. 67.166.145.20 04:22, 20 September 2007 (UTC)

I strongly support 67.166.145.20's views. I think that a band of light in the sky is different from our Galaxy as a dental X-ray (some teeth) is different from the dentition.

Commons:category:Milky Way is a Wikimedia Commons category with images related to the band of light. It is categorized in Commons:category:Milky Way Galaxy, and in the 16 constellations where you can observe the band of light. Then there are 88 constellations in the sky.

I remind that the Solar System is inside the Milky Way Galaxy (Commons link, more secure), though far from its center (8.6 kpc). Hence, we can observe stars of the Milky Way Galaxy in the whole sky, that is the 88 constellations of the sky.

So, the present confusion between “Milky Way” and “Milky Way Galaxy” maintains a major misunderstanding about our universe. --Juiced lemon 11:23, 20 September 2007 (UTC)

Thank you. I think one good addition to the article, on the topic of the band of light, would be a list of the 16 constellations which the band of light passes through, in sequential order. I would be interested in such information as a reader of this article. 67.166.145.20 13:25, 20 September 2007 (UTC)

I think Juiced lemon brings up a very important point: every single (non-supernova) star we see with the naked eye, belongs to the Milky Way Galaxy, but may be nowhere near the Milky Way (band of light) in the sky. The Galaxy, as seen from Earth, is literally all around us. Implicitly identifying the band with the galaxy, by covering both in a single article, thus seems particularly inappropriate. Hqb 16:32, 20 September 2007 (UTC)

In identifying the band with the galaxy, one must remember that it's effectively a density map of the galaxy. The brightest bits (the plane of the galaxy) are naked eye visible from a dark sky. I suspect that if you have sensitive measuring equipment, you'd still be able to detect a (very faint) glow from unresolved stars outside of the main band of the Milky Way. That doesn't mean that it's not there. From many places on Earth, the Milky Way band is not visible at all due to light pollution - doesn't mean it's not there though. Of course the density of stars in a non-spherical object that we're not at the centre of is not spherically symmetrical around the Earth. It is, however, our view of the galaxy. It's obvious that the brightest bits, that is, the bits with the highest surface brightness, show up best. The galaxy is all around us, but there's more of it around us in certain directions. I'm sure that you'd find that the surface brightness would closely be related to the amount of galaxy that exists in that direction. In the direction of the galactic pole, there's only a few hundred parsecs to go before the star density gets very low indeed. In the direction of the galactic centre, there's a few tens of kiloparsecs. We're identifying the band with the galaxy, because that's what it is... Richard B 17:04, 20 September 2007 (UTC)

I'm really impressed with your knowledge of the nature of the physics behind the band of light, Richard B. The information you've shared about why it looks the way it does sounds like particularly interesting material for expanding our coverage of the visual phenomenon... why does it look the way it does? What causes this particular striking visual effect? There seems to be quite a lot of room for expansion.

It is now clearer to me, per WP:Content forking, that at least for now, it is ideal to cover all aspects of the Milky Way in a single article. As long as the treatments of the various aspects of the topic are interwoven throughout the article and not segregated into sections that may imply which aspects are "more important", then a single-article comprehensive coverage seems best, given current Wikipedia policies and guidelines. That's why I suggested merging Milky Way (mythology) back here; that may have been an unintentional content fork, in retrospect. (To be fair, this wasn't my idea; it was suggested to me by an anonymous supporter.)

I look forward to seeing how the article improves. 67.166.145.20 18:23, 20 September 2007 (UTC)

Oh, one more thing... I want to make it clear that I have never supported any claims that the Galaxy is "not there" or that it's "less real" than the band of light. (Nor vice versa, for that matter... they are equally "there" and "real" in my opinion, just in different contexts.) I have consistently cautioned Halfblue against any such claims, throughout this discussion. What I have consistently tried to support is Halfblue's verifiable claim regarding nomenclature, and that there is a difference between the density map of the galaxy and the galaxy itself. I hope that makes things clearer for you, Richard B. I think most of us really are saying the same things, more or less, just in different ways. 67.166.145.20 18:55, 20 September 2007 (UTC)

Additional Sources

Freedman, Roger A. & Kaufmann, William J. (2007). Universe. WH Freeman & Co., p. 600. ISBN 0-7167-8584-6

On a clear, moonless night, away from the glare of city lights, you can often see a hazy, luminous band stretching across the sky. This band, called the Milky Way, extends all the way around the celestial sphere. ... Today, we realize that the Milky Way is actually a disk tens of thousands of parsecs across containing hundreds of bilions of stars -- one of which is our own Sun -- as well as vast quantities of gas and dust. This vast assemblage of matter is collectively called the Milky Way Galaxy.

"Milky Way Galaxy". Encyclopedia Britannica 8. (1998). Encyclopedia Britannica, Inc.

Milky Way Galaxy, large disk-shaped system of stars and interstellar matter of which the Sun is a component. It includes the multitude of stars whose light produces the Milky Way, the highly irregular luminous band that encircles the sky. This band of starlight lies roughly in the plane of the galactic disk.

"Galaxies -- Milky Way Galaxy". Encyclopedia Britannica 19. (1998). Encyclopedia Britannica, Inc.

The Milky Way Galaxy, sometimes simply called the Galaxy, is a spiral system consisting of several billion stars, one of which is the Sun. It takes its name from the Milky Way, the irregular luminous band of stars and gas clouds that stretches across the sky.

Pasachoff, Jay M. (1994). Astronomy: From the Earth to the Universe. Harcourt School, p. 500. ISBN 0-03-001667-3

Don't be confused by the terminology: the Milky Way itself is the band of light that we can see from the earth, and the Milky Way Galaxy is the whole galaxy in which we live. Like other galaxies, our Milky Way Galaxy is composed of perhaps a trillion stars plus many different types of gas, dust, planets, etc. The Milky Way is that part of the Milky Way Galaxy that we can see with the naked eye in our nighttime sky.

Pasachoff, Jay M. (1999). A Field Guide to the Stars and Planets. Houghton Mifflin, pp. 168-169. ISBN 0-395-93432-X

The galaxy we live in, which includes about a trillion (a thousand billion) stars, is called "The Milky Way Galaxy." ... People have long called the band of light that appears to cross the sky by the name the Milky Way because of its appearance; it is the Milky Way from which our galaxy draws its name.

I have more supporting material from the last two; much more from the last one. But that's the core of it.

Sorry for yet another big post; I didn't expect to find so much. I'll add these sources to the citation. 67.166.145.20 00:13, 19 September 2007 (UTC)

Article structure

Currently the intro reads:

The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Γαλαξίας (Galaxias) sometimes referred to simply as "the Galaxy"), is a barred spiral galaxy that lies with the Local Group of galaxies neighborhood of the Universe. Although the Milky Way is one of billions of galaxies in the observable universe,[1] the Galaxy has special significance to humanity as it is the home galaxy of the planet Earth.

Some sources hold that, strictly speaking, the term "Milky Way" should refer exclusively to the band of light in the night sky, while the full name Milky Way Galaxy, or alternatively the Galaxy should be used to describe our galaxy as a whole.[2][3][4] It is unclear how widespread the usage of this convention is, however, and the term "Milky Way" is routinely used in either context.

The sections that follow this are:

1. The view from here - About the band of light
2. Size - About the galaxy
3. Age
4. Composition and structure - About the galaxy
   1. Galactic center
   2. Spiral arms
   3. Halo
   4. Sun's location
5. Environment - About the Local Group and environment outside the galaxy
6. Velocity - Relative motions of the galaxy
7. History
   1. Etymology and beliefs - Perceptions of the band of light
   2. Discovery - Roughly about realizing the band of light are stars and part of a galaxy.

The intro (as of recently anyway) focuses on the galaxy, but is immediately followed by a section that focuses on the band of light and uses the term "Milky Way" to mean band of light. Then there are a set of sections dealing with galactic composition and structure. These could definitely be better organized, since "Size" is basically an aspect of its structure and there is seriously redundancy between "Size" and the intro to "Composition and structure". I would also suggest that "Sun's location" be broken out and a more general section on "Man's relationship to the Milky Way" be written that incorporates both the physical data on position and the information of appearance/perception (i.e. the view), possibly also incorporating the beliefs as a subheading. The section on "Discovery" also has a problem of using "Milky Way" in the two different senses without clearly delineating between them.

The Galaxy is already the more significant topic discussed here in terms of space allocated, but the "band of light" material has basically just been tacked on (at the very end and very beginning). If this is going to be a joint article, then I think it makes sense to begin the discussion by describing the large scale facts as they are know understood (i.e. as a galaxy) and then follow that with information on how that galaxy is percieved (e.g. as a band of light) and the history of the surrounding beliefs/understanding.

So, my proposed outline might look like:

1. Composition and structure (With Size and Age folded into the intro portion)
   1. Galactic center
   2. Spiral arms
   3. Halo
2. Extragalactic Environment
3. Velocity
4. Man's relationship to the Milky Way
   1. Position of the solar system
   2. Visual appearance of the Milky Way
   3. Etymology and beliefs
   4. History of scientific understanding

I also think it is bad that all the introductory images focus on the appearance and none show spiral structure.

76.231.189.193 19:41, 20 September 2007 (UTC)

I like the direction of this approach. This seems the right path toward a better, more comprehensive article. I have some personal differences of opinion about the optimal order of presentation, but those are just that, my opinions, and I trust that at this point the natural consensus process will lead us in the right direction. For what it's worth, my opinion on order of presentation is that what you propose as section 4 should be moved up to section 1. Such an approach seems to me to have an appealing flow. However, in order to get to the nitty-gritty scientific facts about the galactic structure more quickly, a bit of the "Man's Relationship" section should probably be separated out and included elsewhere... I would recommend separating out "Etymology and beliefs" and putting it at the end.

Also, I think a (very) brief mention of the band of light should be added to the first paragraph, for flow and readability of the lead. I'll take a stab at that now, and let others muck about with things from there. 67.166.145.20 21:59, 20 September 2007 (UTC)

I see that a lot of discussion has ensued over the last month with regard to the nature of the Milky Way article. I'm so glad the article is still primarily about the galaxy. I'm all for the band of light definition being part of the introduction to this article. The historical context and the relationship that we have to this object, from our blue dot, is very important. In terms of structure of the article I think the original GA article is a good bases to start.

As for the first paragraph : "The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Γαλαξίας (Galaxias) sometimes referred to simply as "the Galaxy"), is a barred spiral galaxy that lies with the Local Group of galaxies neighborhood of the Universe, visible from Earth as a band of light in the night sky.", apart from the spelling mistake which I will correct now, I much prefer the introductory paragraphs of the original GA article. It includes the band of light and talks about it in a much more scientific fashion. Alisdair37 16:28, 2 October 2007 (UTC)

In fact upon correcting the spelling mistake I realise the whole first sentence does not make sense. I hesitate to correct it as others may have a view on the matter. Alisdair37 16:38, 2 October 2007 (UTC)

Grammatically, it seems to more or less make sense, but it's very confusing. I think, at the very least, the stuff about the origins of the name should be demoted to the second sentence, rather than being placed in parentheses. I also think that the fact that it is our galaxy needs to be in the first sentence. A better opening paragraph might be:

The Milky Way is a moderately-sized spiral galaxy, notable chiefly because it is home to our own Sun and, of course, the planet Earth. Its name in English is a translation of the Latin Via Lactea, which in turn derives from the Greek Γαλαξίας (Galaxias). From the surface of the Earth, it appears as a band of diffuse light stretching across the night sky and visible to the naked eye from a dark location (some sources hold that, strictly speaking, the term "Milky Way" should refer exclusively to this band of light, and prefer the longer name Milky Way Galaxy, or simply the Galaxy—with the first letter capitalised—to describe our galaxy as a whole; however, the term "Milky Way" is routinely used in either context).

It can certainly be improved upon, but that's the best I can come up with at the moment, so I throw it out there for general comment. Cosmo0 20:06, 2 October 2007 (UTC)

I certainly can appreciate the need for such improvements in the lead. While I think the current version was a far better compromise than the previous situation, I agree that improvements can and should be made. Please be assured that, for my part, I do not impose any such improvements to the lead, as long as no important information is lost in the process, and I intend to limit my own future editorial work to improving the grammar and clarity of nomenclature of the article as it improves. Theindigowombat 23:43, 9 October 2007 (UTC) (The user formerly known as 67.166.145.20)

By the way, someone mentioned the need for an image focussing on the Milky Way as a galaxy rather than a band of light. Obviously there are no photographs of the Milky Way from outside the galaxy, but here is an artists impression based on observations. Anyone want to suggest if/where it should go in? Cosmo0 19:04, 3 October 2007 (UTC)

Actually, I just looked at the reviewed version of the article and the image appears in there, but was apparently removed since. Cosmo0 19:08, 3 October 2007 (UTC)

GA status

This article appears to have undergone a massive amount of change and it may no longer satisfy the GA criteria. In particular there are numerous "citation needed" tags and there are several sections that are weakly cited or not at all. It's also not clear that the other GA criteria are still met. Should the GA status be stripped? Thanks. — RJH (talk) 15:45, 3 October 2007 (UTC)

It does appear to have undergone a lot of change and should probably be re-assessed at some point. Cosmo0 19:10, 3 October 2007 (UTC)

I agree that the quality of the article needs to be much improved in order to retain its GA status. I hope that some time can be allowed to restore it to such a state, while retaining the necessary recent improvements regarding nomenclature. I also think there should be some more discussion about what guidelines of nomenclature should be followed within the text of the article itself, as a semi-official style guideline. Beyond such concerns of accuracy of nomenclature, however, I agree that something closer to the old GA version would be far preferable to the current level of detail and quality.

I happen to have in my possession a complete rewrite of a different version of the article which in many ways seems superior to both previous rated versions and to intermediate compromises. This was deposited in my documents folder on my system anonymously by a benign intruder when I was posting under my then-current IP address. I would happy to share this version as a stimulus to discussion, and to generate ideas. However, I'm unsure of the appropriate way to do so, both socially and techinically. If others wish to see this version, feel free to discuss it with me on my talk page and I'll try to find a good way to present this content to others. Theindigowombat 23:58, 9 October 2007 (UTC) (The user formerly known as 67.166.145.20)

I disagree. Your "complete rewrite" (which appears on your talk page) is merely a revised version of the aforementioned GA page, in which you have added "Milky Way Galaxy" in an attempt to change the name of the article. I suggest the entire article be reverted to the GA version and we go from there. —Viriditas | Talk 01:11, 19 October 2007 (UTC)

Nix that. I fulfilled all outstanding cite requests. Problem solved. —Viriditas | Talk 01:33, 19 October 2007 (UTC)

As I said on my talk page, I realized after I posted it there that the article was not as different as I thought it was when I first read it. My error was apparent to me once I saw it rendered as a Wiki page, and not as a simple text file. I acknowledged this misperception on my part on my talk page, and I apologize for not making a note of this here as well; I was attempting to reduce my activity level here to a more modest pace of contributions, and did not want to flood the page with my own activity again. I agree that a reversion to the GA version seems like a very good idea, and I would fully support it. The new information regarding nomenclature can be integrated fairly easily.

As for your conclusion regarding the goal I was attempting to attain, I would greatly prefer if you did not state such deductions as fact, as I find such statements upsetting. In fact my goal was to stimulate additional discussion about the degree to which the formal nomenclature should be adhered to in the text of a Wikipedia article, as I attempted to state earlier. While one possible outcome of such a discussion might be a name change, and while I would support such a change, I don't regard that as a particularly likely outcome at this point, and it's not a personal goal of mine anymore. My current concern is to establish a consensus for a consistent guide to nomenclature to be followed in the future, which would require additional discussion about the merits of using the formal nomenclature versus the more common term. This is primarily in regards to the usage of terms in the text of the article itself, although complete adherence to formal nomenclature would imply a change of title. I perceive reasonable arguments both for the common term and for the formal nomenclature, and believe it would be best to discuss the matter further. I do not wish to inappropriately dominate the discussion as I did last month, however, and would prefer to step back and give others a chance to weigh in on the matter. I would greatly appreciate it if you would assume good faith on my part as regards my honesty about my stated goals and intent. Thank you. Theindigowombat 05:32, 19 October 2007 (UTC)

I apologize if I made the above comments in haste. Upon careful consideration, I discovered an even more serious error on my part that may have confused the issue. I was incorrect about the source of the alternate version of the article when I discovered it in my documents folder; your feedback and reactions prompted me to reconsider some of my basic assumptions and I realized that it was simply a version of the article that I had saved during my earlier editorial work, then forgotten. I apologize for any confusion that this admittedly bizarre error on my part may have caused, and I can appreciate how this error may have contributed to some skepticism about my veracity. I humbly apologize for my oversensitivity to accusations of deceit. Thank you for helping to alert me to this error in my reasoning process. Theindigowombat 06:34, 19 October 2007 (UTC)

Alternate version for consideration

As I mentioned above, an anonymous contributor left an alternate version of the Milky Way Galaxy article in my documents folder when I was posting unsecurely through my IP address. I have put this version up on my talk page as a stimulus to discussion and to generate ideas. I hope that some find it helpful. Please feel free to check it out at your convenience. Theindigowombat 12:26, 12 October 2007 (UTC) (The user formerly known as 67.166.145.20)

I was incorrect about the source of this version of the article. It was simply an earlier version of the article that I had saved, forgotten about, then rediscovered and took as evidence that my system had been accessed by someone other than myself. I apologize for any confusion and skepticism that this admittedly bizarre error on my part may have caused. Theindigowombat 06:34, 19 October 2007 (UTC)

Visibility

I'm sure many people would be quite interested in the potential...photographability (word?) of the galaxy's center. I know I am, though I'm hardly a decent spokesperson for other popular-science-types. I've tried to do some research as far as how to go about explaining location, photographic technique, etc., but I'm wondering if a section on this should be included. "Are those photos taken from the locations they are because that location offers something specific, or will any dark place do?", "What's the exposure time/type of camera?", etc. These questions can be thus answered. —Preceding unsigned comment added by 24.3.13.191 (talk) 00:25, 29 October 2007 (UTC)

If you're interested in doing something along those lines, you may first want to take a look at the guidelines in WP:NOT#HOWTO. If what you're thinking of is more of a "how-to" guide then it might be more appropriate to put it in one of the other projects mentioned in the guidelines (such as Wikihow) and link to it from this article (I think that's possible although I've never tried it). Cosmo0 14:26, 29 October 2007 (UTC)

Volume of the galaxy

Sorry if this is obvious to others, but I can't seem to find what units the galaxy volume is measured in, what is considered edge of the galaxy, and how the volume is calculated for the galaxy. --Mrg3105 03:00, 11 November 2007 (UTC)

I'm not sure what you're referring to. I searched for 'volume' in the article and I can't find any reference to it. In any case, as you rightly said, defining a volume for the Galaxy would be difficult because it doesn't have a sharp edge. Cosmo0 15:43, 11 November 2007 (UTC)

THAT was precisely my point, that the calculation for volume, and definition of where in space the galaxy ends is not there. What defines the 'edge' of a star system? Probably extent of its gravitational field? The galaxy also has one, though I don't know how far that extends. Any object which is not trapped by this field would be outside of the galaxy and therefore all objects that are within this field are within the volume of the galaxy? Is this a correct assumption?--Mrg3105 03:15, 12 November 2007 (UTC)

OK, I just wasn't sure whether you were criticizing something in the article or suggesting something new. What you describe would be a sensible way to define it and would give you essentially the volume within the virial radius of the dark matter halo (or something close to it). The virial radius defines the boundary between matter that is still collapsing onto the galaxy (outside the virial radius) and matter that is in dynamical equilibrium. Of course, that's difficult to measure directly, because it is much larger than the extent of the main stellar component and is dominated by the dark matter. It's been estimated (using some very complex theoretical modelling) to be around 200-300 kpc, but it's really not well constrained. Cosmo0 17:55, 12 November 2007 (UTC)

Galactic magnetic field?

Can someone please ad a section or subheading for the galactic magnetic field, strength, how it's generated, etc? This seems to be a rather big oversight, unless I've completely missed it in the article. Mgmirkin (talk) 16:26, 14 December 2007 (UTC)

Assume that most, if not all of the below references should be fairly non-controversial? If not, I'm sure someone could cite additional peer-reviewed sources such as Hannes Alfven's work.

http://hypertextbook.com/facts/2001/RebeccaRudberg.shtml

http://www.aas.org/publications/baas/v29n2/aas190/abs/S024001.html

http://public.lanl.gov/alp/plasma/downloadsCosmo/Peratt86TPS-I.pdf

http://public.lanl.gov/alp/plasma/downloadsCosmo/Peratt86TPS-II.pdf

http://focus.aps.org/story/v12/st24

http://csep10.phys.utk.edu/astr162/lect/milkyway/components.html Mgmirkin (talk) 16:26, 14 December 2007 (UTC)

The galactic magnetic field is measured mostly through polarization studies with maybe a little synchrotron thrown in. The best place to get reliable sources on the matter is from NASA Adsabs. ScienceApologist (talk) 17:23, 14 December 2007 (UTC)

Our Solar System?

What if someone is not from Earth? —Preceding unsigned comment added by 199.48.25.10 (talk) 15:31, 26 May 2009 (UTC)

ebay

Um... Anybody notice that The Milky Way has been put up for auction on eBay? SHould this be mentioned within the article? 71.97.240.153 (talk) 04:52, 4 June 2008 (UTC)

I'd say no, it's not really relevant. Serendi^podous 09:51, 4 June 2008 (UTC)

How much?--92.118.191.48 (talk) 23:58, 9 November 2008 (UTC)

Thickness of gas

I deleted (diff) the thickness of the gas from the lead table. The number that was there referred to the warm ionized gas, which is only one of many components of the interstellar medium of the Galaxy. If we are going to quote a gas thickness of the Galaxy, it should probably be that of the neutral gas, but there is warm and cold neutral gas to confuse the picture further. See Table 1 in interstellar medium. —Alex (ASHill | talk | contribs) 14:38, 21 July 2008 (UTC)

Is the glowing band an asterism?

Does the glowing "Milky Way" band in the sky classify as an asterism? If so, this should be mentioned in the article. SpectrumDT (talk) 13:06, 5 August 2008 (UTC)

• A asterism is a pattern of stars. I've never heard of the Milky Way being classified as such, since individual stars in it are only visible with a telescope. --Etacar11 13:09, 5 August 2008 (UTC)

"Artist's Conception" image

The image entitled "Artist's Conception" is striking, but there's a spelling error within it. I've always spelled it 'longitude', not 'longitIde'. It's at the top of the image. Any ideas how to fix that?

Even 'painters' have to use Spell Check. 68Kustom (talk) 01:42, 24 September 2008 (UTC)

Hmm, sure enough; that's a shame. Not much we can do unless someone wants to edit the image, but maybe we can get NASA to release a fixed version.

I found a version with the correct spelling (http://www.spitzer.caltech.edu/Media/releases/ssc2008-10/ssc2008-10b.shtml) and uploaded it; problem should be fixed now. Thanks. —Alex (ASHill | talk | contribs) 16:36, 24 September 2008 (UTC)

Infobox colour

Why does this infobox use #30d5c8 colour? As far as I can see thic colour is used for quasars' infoboxes (for example 3C 273, Einstein Cross, but not 3C 279), and the colour #aaffcc8 is used for galaxies (for example Andromeda Galaxy). If an infobox should be here, at least one is certain - the Milky Way Galaxy is not a quasar. And secondly, some other wikipedias are copying infoboxes from here (ko, ms, sd, sl, te). --xJaM (talk) 16:55, 25 September 2008 (UTC)

wake or wave?

The Environment section describes effect of Magellanic Clouds as "...the movement of these two galaxies creates a wake that influences the larger Milky Way". I wonder whether wake is right here or 'gravitational wave' is better? manya (talk) 08:47, 8 October 2008 (UTC)

First, a caution: The phrase gravitational wave refers (in the physics community) to the propagation of the gravitational interaction through gravitons. (Compare electromagnetic wave, propagated through photons.) That is certainly NOT the phenomenon at issue here. The interaction here is tidal.

Second, the word wake seems particularly appropriate for this phenomenon: It is a wave specifically caused by a transient interaction with an external body, just as is a ship's wake. However, this seems to be a matter of writing style, not denotation. I suggest leaving it as is. Purely my opinion -- but the choice of word is itself purely a matter of opinion. Jmacwiki (talk) 06:40, 14 October 2008 (UTC)

You could see it in the sky! —Preceding unsigned comment added by 69.231.239.188 (talk) 23:25, 16 October 2008 (UTC)

Poor introductory paragraph

The introductory paragraph takes too long to get to the rather important point that the Milky Way galaxy is the one that we live in. That is surely one of the most significant things about it. The first sentence should be something like "The Milky Way is the galaxy in which Earth and the solar system are located." —Preceding unsigned comment added by 81.105.54.65 (talk) 18:42, 25 October 2008 (UTC)

sergi el millor

hola dedico la pagina al meu amic guapo al gerard —Preceding unsigned comment added by 213.98.172.72 (talk) 09:30, 18 November 2008 (UTC)

...Wha?

This pic appears twice in the article......one caption says:

"Using infrared images from NASA's Spitzer Space Telescope, scientists have found that the Milky Way has two major arms"

the other....:

"Artist's conception of the spiral structure of the Milky Way with two major, stellar arms and a bar." This one has a citation, has lines, and names some the of the...stellar arms..

Sooo.....this this pic an artist's picture, or made by NASA's telescope??? 75.72.221.172 (talk) 03:49, 4 January 2009 (UTC)

Removed first occurrance, kept artist's conception one. Vsmith (talk) 04:00, 4 January 2009 (UTC)

News article = "Milky Way Galaxy: Snack-Sized No More"

• Milky Way Galaxy: Snack-Sized No More Ling.Nut ^{(talk—WP:3IAR)} 03:29, 6 January 2009 (UTC)

Why is this fact not reflected in the summary? The mass there is still 580 billion solar masses while the latest findings which are also mentioned in the article itself indicate a mass of 3 trillion SM. The new fact is reflected in several major articles that explicitly state the Milky Way's mass is now estimated to be 3 trillion SM, "50% bigger than previously estimated" which puts the previous estimate at 2 trillion SM already.

• This article on space.com is an example.

I tried to change the value but it was rolled back on the grounds that there had been no consense previously. Pardon? These are the latest findings and should be incorporated. Dgennero (talk) 19:55, 18 July 2009 (UTC)

Major new discovery, plus a newer, better image of the Galaxy's core.

[16]

The picture of the core is excellent. Much better than the one we currently have. Zazaban (talk) 22:09, 6 January 2009 (UTC)

The link you supplied is to an artist's conception; not a photographic image Stefansquintet (talk) 15:16, 21 January 2009 (UTC)

There is no current way to photograph the Milky Way Galaxy. That would require having a satellite/spaceship/telescope positioned somewhere outside our galaxy(at least 10000 LY away from our Sun, to get a good picture). I've made a java application based on that picture at http://www.3dgalaxymap.com/Galaxy/ Raydekk (talk) 10:20, 26 January 2009 (UTC)

There seemed to be two additional hyphens in the url you supplied, I believe http://www.3dgalaxymap.com/Galaxy/ is the link you meant to supply. That's a pretty application you have made :) Jdrewitt (talk) 16:16, 26 January 2009 (UTC)

Thanks for spotting that :) also here is some info on the Far 3kpc arm of the Milky Way Galaxy http://apod.nasa.gov/apod/ap080711.html Raydekk (talk) 17:56, 26 January 2009 (UTC)

Sun's Location

"This is very similar to how a simple harmonic oscillator works with no drag force (damping) term. These oscillations often coincide with mass extinction periods on Earth; presumably the higher density of stars close to the galactic plane leads to more impact events.[36]"

Is there any knowledge of when it's passed through the galactic plane, or when the next passing will be —Preceding unsigned comment added by 60.234.155.105 (talk) 09:22, 2 February 2009 (UTC)

2012 —Preceding unsigned comment added by 156.34.170.87 (talk) 01:24, 25 January 2010 (UTC)

Our Solar System?

It's a bit self-centered (referring to earthlings) to say that:

The Milky Way, sometimes called simply the Galaxy, is the galaxy in which our Solar System is located.

Wikipedia should be able to transverse time and English speaking species. What happens when wikipedia in the future is read from people who don't live in this galaxy? What happens when aliens start tuning into Wikipedia for a crash course hitch-hikers guide to the milky way. It should read "The Milky Way, some times called simply the Galaxy, is the galaxy in which planet Earth is located."

Who's with me?Wgfcrafty (talk) 06:11, 27 February 2009 (UTC)

According to your logic it would be equally self-centered to state the "milky way is the galaxy in which the planet Earth is located" considering the Milky way contains 200-400 billion stars - who knows how many of these have solar systems of their own and Earth like planets of their own. But anyway, don't be so silly. Jdrewitt (talk) 08:40, 27 February 2009 (UTC)

In four billion years I'll be the one having the last laugh. Or at least some one will be reading this discussion and laughing for me. Wgfcrafty (talk) 16:28, 27 February 2009 (UTC)

Well as funny as you are this is for serious discussions :) Jdrewitt (talk) 18:26, 27 February 2009 (UTC)

If one wanted to be 100% "objective", humanity and Earth would have to be an aspect of the galaxy, rather than the other way around. Something along the lines ...it is the only known galaxy with a civilisation...

I agree that one could perhaps remove our, as it feels unencyclopedic. I.e. ...is the galaxy in which the Solar System is located. --Harald Khan Ճ 20:55, 27 February 2009 (UTC)

Its not really unencyclopedic just a matter of tense, although I agree "the" is preferable to "our" since it is more scientific. Having said this, it is only human beings reading so is technically correct as it is. Jdrewitt (talk) 21:50, 27 February 2009 (UTC)

Made the change. Jdrewitt (talk) 21:54, 27 February 2009 (UTC)

No one outside this galaxy is going to read this for tens of thousands of years, you know. —Tamfang (talk) 05:18, 15 July 2009 (UTC)

Typo in "Observation Data"

On the right-hand column at the top of the page it reads "Oldest known star 13.2 million years". Surely this should read billion. I'm a total rookie at WP, I'll leave it with you guys. —Preceding unsigned comment added by 109.255.156.186 (talk) 13:38, 13 February 2010 (UTC)

Yes, that does seem incorrect. -RadicalOne•^{Contact Me}•_{Chase My Tail} 17:30, 13 February 2010 (UTC)

Update: That edit was vandalism, now reverted. -RadicalOne•^{Contact Me}•_{Chase My Tail} 17:31, 13 February 2010 (UTC)

"negative rotation"

Sun's galactic rotation period : 220 million years (negative rotation)

Eh? Does that mean a retrograde orbit, or that the overall rotation within the Solar System is retrograde relative to that of the Galaxy, or what? —Tamfang (talk) 21:07, 11 March 2009 (UTC)

Milky Way Analog

Messier 109 is being used as a possible analog for the Milky Way, yet the picture is very poor in quality.

I propose using NGC 1300, which is a barred spiral galaxy like the Milky Way, with a far better picture.

Rick Evans (talk) 05:06, 29 May 2009 (UTC)

Good Article!

I've been reviewing this article, and have determined that it meets the qualifications for Good Article Status. It is well written, is factual and well cited, broad in coverage, neutral in tone, stable, and well imaged. I made the small change of including the Galaxy infobox, but otherwise haven't been a part of the editing of this article.

Now that it is a Good Article, editors should review the qualifications for Featured Article Status and set their standards high! This could be a Featured Article at some point, if it continues to improve. Phidauex 20:51, 18 June 2006 (UTC)

Arms controvercy

The article associates Norma arm with Cygnus arm, but the picture shows that Cygnus arm as associated with Orion arm.--79.111.4.155 (talk) 11:59, 23 July 2009 (UTC)

You're right, "Norma arm" is in purple along with the "outer arm" and the "new outer arm", the "orion-Cygnus arm" is orange. I will change the text accordingly, assuming the diagram is accurate! Thanks. Jdrewitt (talk) 22:02, 23 July 2009 (UTC)

Rotational speed vs Tangential speed

In the section labeled Size the term "rotational speed," a measure of cyclic frequency expressed as rotations per unit time, seems to have been used incorrectly to indicate a tangential speed:

"The newer and more accurate estimate of the galaxy's rotational speed (and in turn the amount of dark matter contained by the galaxy) puts the figure at about 254 km/s...."

Shouldn't that be changed to "tangential speed?"

Toadzha (talk) 21:04, 19 August 2009 (UTC)

That would be equally wrong: there's no one speed applicable to the whole of the Galaxy. May one suppose that what's meant is the speed of the Solar System relative to the Galaxy? —Tamfang (talk) 23:55, 19 August 2009 (UTC)

Yes I guess it should be changed to "orbital velocity of the sun around the galactic centre", but I'm not certain which object they've actually measured. See also the graph under Velocity and Galaxy rotation curve, which claims observed orbital speeds are almost constant.

As is typical for many galaxies, the distribution of mass in the Milky Way Galaxy is such that the orbital speed of most stars in the Galaxy does not depend strongly on its distance from the center. Away from the central bulge or outer rim, the typical stellar velocity is between 210 and 240 km/s.[26]

There is one more inconsistency as to the mass of the galaxy:

This in turn implies that the Milky Way has a total mass equivalent to around 3 trillion Suns, about 50% more massive than some previously thought.

This conflicts with

The Milky Way's mass is thought to be about 5.8×10¹¹ solar masses (M_☉)

which is only about a fifth of the 3 trillion suns.

Number of stars - inconsistent numbers

In the top right table the number of stars is given as Aprox. 100 Billion, and in the article we read

It is estimated to contain at least 200 billion stars[9] and possibly up to 400 billion stars,[10] the exact figure depending on the number of very low-mass stars, which is highly uncertain. —Preceding unsigned comment added by 90.195.11.155 (talk) 12:43, 25 August 2009 (UTC)

"The article misquotes its source. The source it sites claims the milky way has a mass equivilant to 200 billion SOLAR MASSES. This just means that if you added up all the mass of the solar system it would be 200 billion solar masses, not that we have 200 billion stars in our galaxy. It is correct that we have approx. 100 billion. We just need a better source citing it." —Preceding unsigned comment added by 128.197.64.113 (talk) 16:13, 15 January 2010 (UTC)

ace

i like milky way bars milky way bars r really fine :] —Preceding unsigned comment added by 194.105.165.178 (talk) 15:12, 28 August 2009 (UTC)

You want Milky Way bar, then. —Tamfang (talk) 16:13, 28 August 2009 (UTC)

Oscillation Cycle Position

The article notes that "... the Sun oscillates up and down relative to the galactic plane approximately 2.7 times per orbit."

It would be useful to note where we are in that oscillation, at least to debunk the hysteria about the earth "passing through the Galactic Plane" in 2012 ... allegedly prompting some kind of Armageddon.

The article seems to add credence to this speculation by noting the Gillmana1/Erenlera1 correlation with historic biological extinctions. The Cambridge link only offers an abstract (unless someone wants to spend $45 for the full study), which isn't very clear about the "three time zones of high geological activity" related to the oscillation, nor where we are in those zones. If it must be cited, it needs some clarification. Westmiller (talk) 06:54, 12 November 2009 (UTC)

Good point. While checking citations of Gillman Erenler I found a solid refutation of their conclusions in Overholt et al. I've put it in the article so we can all rest easy about impending doom. User:Jandrews —Preceding unsigned comment added by 208.38.200.62 (talk) 18:01, 9 July 2010 (UTC)

Part of the Milky Way

It appears from this article in the New York Times, that even in 1900, people still considered the Milky Way separated from the Solar System (a distant celestial body)... [17] ... was this a mainstream view in society, and when did that change? That should be added to the history section, if we can come up with some more sources. 76.66.197.2 (talk) 11:41, 12 November 2009 (UTC)

In 1874, it does not appear to have been accepted that the Milky Way was a coherent grouping... [18] 76.66.197.2 (talk) 12:15, 12 November 2009 (UTC)

The universe is 500 lightyears in size and the Sun is not part of the Milky Way... 1914 [19]. 70.29.209.121 (talk) 13:18, 4 December 2009 (UTC)

recent minor changes

I can accept "our solar system" or "the/our Solar System", but "the solar system" won't do: there are millions (at least) of small-s solar systems in the galaxy. Since there's strong opinion against "our", I changed it back to "the Solar System".

The stellar disk of the Milky Way Galaxy [...] is considered to be, on average, about 1,000 ly (9.5×10¹⁵ km) thick.

considered is a recent change from believed. It connotes to me that the number depends more on a question of definition than on measurement. Is that why it was changed? If not, what's wrong with believed? Are existing measurements good enough that 'belief' on the subject is outmoded?

dwarf galaxies [...] that have already been cannibalized by the Milky Way

Is cannibalized standard language? Why not a less dramatic word like absorbed? Is there some sense in which the galaxy is nourished (not merely fattened) by consuming smaller ones? —Tamfang (talk) 18:45, 15 November 2009 (UTC)

1. The definition of "solar" is: of or pertaining to the sun. Since the sun is the name of the star which earth orbits, there is only one solar system. Technically any other similar systems in the galaxy must be described as stellar systems and not Solar systems. So it is perfectly correct to describe our stellar system uniquely as "the solar system".
2. The thickness of the stellar disk should be cited using reliable sources. If there are not any reliable sources to back up what thickness the stellar disk is "considered" to be then the statement should be removed.
3. I agree "cannibalized" should be changed to absorbed or a synonym of absorbed. Jdrewitt (talk) 20:42, 15 November 2009 (UTC)

To point #1: Alas, the phrase stellar system is already in general use in astrophysics. It usually refers to aggregations, not of planets around stars, but of stars around their common center of mass, whether small (clusters) or large (entire galaxies).

So distinguishing our star+planets from other stars+planets by capitalization (our "Solar System" vs. other "solar systems") may be the best recourse -- unfortunately. In this case, the usage would mimic that of referring to other stars as "suns", although that is usually poetic usage. Jmacwiki (talk) 05:10, 16 November 2009 (UTC)

"Solar system" is not the correct terminology for other star systems. There is only one sun and so it is just incorrect. I know for certain that leading academics in the field of searching for extrasolar planatary systems would NOT be referring to new systems as "solar systems". In fact "extrasolar systems" or just simply "planatary systems" are terms much more likely to be used by academics. Jdrewitt (talk) 09:44, 16 November 2009 (UTC)

As I say, we are caught between prior usage, which has appropriated the term stellar system to mean something quite different, and poetic usage, which is (IMO) unhelpful in an encyclopedia. "Planetary system" may be fine, and the best we can do, despite having no analogy to "Solar System".

As for "it is just incorrect", well .... usage changes. Etymology isn't everything. It is equally "just incorrect" to refer to the Earth as a planet [Greek: wanderer], i.e., a wandering point of light in the (Earth's!) sky. And yet, considering the Earth as a planet is much more useful than considering it as the center of the universe. Etymology isn't everything. (FWIW, I, too, strongly prefer etymology to the vagaries of uninformed popular usage. But I'm not picking this one as one of my battles.) Jmacwiki (talk) 03:30, 17 November 2009 (UTC)

I don't understand why you have decided to argue the point but you seem to be in agreement that "solar system" is not the correct term for other planatary systems so we'll leave it at that. Jdrewitt (talk) 10:03, 17 November 2009 (UTC)

A linguistic note: in a context where "the solar system" is unambiguously identifiable, such as "our solar system" have been mentioned a little before without any intervening possibilities of confusions, then "the solar system" should be accepted, just consider it being an elaborate form of the pronoun form "it". Another semi-short form relevant for solar system usage is "our system". A efficiency point is however that when using "the solar system", an equally effective form is "our solar system", which is better defined. ... said: Rursus (^mbork³) 09:55, 19 December 2009 (UTC)

The question, unfortunately, is what to call it in the article's first sentence. —Tamfang (talk) 20:27, 19 December 2009 (UTC)

FWIW, Galactic cannibalism is a standard term in the field. I think it's stupid that it is, but it is. ScienceApologist (talk) 17:44, 19 December 2009 (UTC)

Wow, an answer to one of my questions! Thanks. —Tamfang (talk) 20:27, 19 December 2009 (UTC)

Different "photon velocities" ?

In the Velocity section is the sentence..

The Milky Way is moving at around 552 km/s with respect to the photons of the CMB

http://en.wikipedia.org/wiki/Milky_Way#Velocity

It is a fundamental postulate of relativity that the speed of all light is the same in all directions. This quote suggests the EM waves are passing us at different speeds depending on the direction from which they are coming.
May I suggest something like...

The Milky Way is moving at around 552 km/s with respect to the reference frame established by the radiation making up the CMB.

Dave 2346 (talk) 15:06, 24 December 2009 (UTC)

More completely: You confuse the relative speed of a source (the atoms that emitted the photons of the CMB) and a receiver (us, in the MW) of photons with the speed of the photons themselves when received by us. The latter is indeed constant. But the frequency of the photons changes instead, as the relative source/receiver speed changes, and this is what allows us to decide on the 552 km/s speed of the Milky Way: In two opposite directions on the sky (think of North & South Poles), we see frequency changes of +552 and -552 km/s compared to the circle of intermediate directions (think of Equator). Jmacwiki (talk) 04:37, 25 December 2009 (UTC)

Only one frame of reference

In the Velocity section it is stated that there are two different possible "preferred frames of reference", one with respect to the "Hubble flow" and one with respect to the CMB. However, if I understand the reference correctly, these two are actually the same. The velocity of 630km/s of the "first" reference frame is, also according to the reference and CMBR dipole anisotropy, not the galaxy velocity but the Local Group velocity. The galaxy is than again moving within this Local Group giving it a velocity with respect to the CMB (or Hubble flow) of 552 km/s (I did not check this number). There is thus only one "preferred frame of reference" and I suggest to call it just the "reference frame of the CMB". --Jmdx23 (talk) 22:42, 7 January 2010 (UTC)

school project

Hi i am doing a school praject on the milky way can any one help me with head titles or infomation???? —Preceding unsigned comment added by 99.235.238.178 (talk) 05:09, 9 January 2010 (UTC)

If you don't find what you need in the article, please ask a more specific question. —Tamfang (talk) 02:40, 12 January 2010 (UTC)

Here's some information that may help you. You'll get a better grade if you write like this:

Hi. I am doing a school project on the Milky Way. Can anyone help me ...?

HTH. —Tamfang (talk) 02:42, 12 January 2010 (UTC)

Right on, Tamfang! Jmacwiki (talk) 03:38, 21 January 2010 (UTC)

Standard distance units

This article flip-flops between using light years and parsecs as units of distance. I think it would be good if it only used a single unit consistently.—RJH (talk) 20:46, 19 January 2010 (UTC)

Any preference? Mine is for light years as this is far better known to the average lay-reader. Casliber (talk · contribs) 21:02, 19 January 2010 (UTC)

Definitely. Also, it seems far easier to explain -- and therefore for the average reader to understand -- how a light year is defined (distance light travels in a year) than how a parsec is (206,265 * Earth-Sun distance). Jmacwiki (talk) 03:35, 21 January 2010 (UTC)

B Class?

Only B class? Sephiroth storm (talk) 04:03, 22 February 2010 (UTC)

Nominate it for GA if you think it's ready. ScienceApologist (talk) 05:52, 22 February 2010 (UTC)

The article was GA until July 2009 when it was delisted as part of the GA sweeps, see Talk:Milky_Way/GA1. Polyamorph (talk) 08:15, 22 February 2010 (UTC)

It'd be great to get it back to GA - why not take a look and think about what needs to be done - a to-do list of sorts...Casliber (talk · contribs) 10:46, 22 February 2010 (UTC)

The article as it is looks GA quality, I don't think it would be too much trouble getting it promoted. The main issues from the GA delisting were

1. Copy edit needed.
2. Improve the prose where necessary.
3. Expand the lead.
4. Ensure all areas are cited and replace the {{citation needed}} tags with verifiable sources.

Polyamorph (talk) 11:55, 22 February 2010 (UTC)

Before copyediting, one should always review comprehensiveness. Are we satisfied the article is fully comprehensive? I haven't looked at it yet myself. Casliber (talk · contribs) 12:52, 22 February 2010 (UTC)

• One thing that is missing in the section about the halo is mention of High velocity clouds and a more complete description of the tidal streams and globular clusters. ScienceApologist (talk) 12:56, 22 February 2010 (UTC)

• The Dark matter halo is interesting and only touched upon in this article, while there is a sizeable segment on the milky way's dark matter halo at Dark_matter_halo#Milky_Way_dark_matter_halo. I'd buff it in this article myself but I am a neophyte at some of these concepts - is the dark matter halo widely accepted? Casliber (talk · contribs) 13:04, 22 February 2010 (UTC)
  • The only evidence we have for it is indirect and there are those observers who would argue that it is not a "part" of the Milky Way per se. Unlike external galaxies, the rotation curve of the Milky Way is notoriously difficult to measure and the mass of the Milky Way is still something of an outstanding question. Evidence for dark matter in the disk of the galaxy coming from the Oort constants has now been thoroughly debunked. However, people who build theoretical models of the galaxy absolutely do consider it vital to its structure and formation and cosmological theories all but demand its existence. Additionally, it's also kinda cutting edge right now to think that the best chance we have for a direct detection of dark matter is looking at the center of the Milky Way where the so-called WMAP haze lies. Yeah, there might some room to discuss dark matter in our galaxy. ScienceApologist (talk) 13:10, 22 February 2010 (UTC)

• • • SA if you want to have a go at incorporating the shtuff to the right level of depth and consensus yada yada (as I have no idea!), I can play with massaging and smoothing the prose and constructing a lead. Of course everyone else is welcome as well :) Casliber (talk · contribs) 23:48, 22 February 2010 (UTC)

• • • • Hmm, I'm not sure I can dig up the appropriate sources to do this and it is seriously something outside of my field of expertise. I'll ask one of my colleagues if they'll have a go at it. ScienceApologist (talk) 23:45, 23 February 2010 (UTC)

Inconsistent mass entries

Twice, this article states that the Milky Way has a mass of 5.8 × 10¹¹ M☉. It then goes on to state that there is about 6 × 10¹¹ to 3 × 10¹² solar masses of dark mater, which far exceeds this previous number. Also, the mass of the Milky Way is routinely said to be comparable to that of the Andromeda Galaxy, given as 1.23 × 10¹² M☉ in its own article. This article also happens to state the Milky Way is 1.9 × 10¹² M☉, which makes a lot more sense. Also, the cited sources for the Milky Way mass seem to be a bit out of date, if I am to understand these recent mass adjustments taking dark matter into account properly.Rip-Saw (talk) 00:25, 20 March 2010 (UTC)

I found an article here that is considerably more current: http://arxiv.org/abs/0801.1232 but I cannot make head or tails of what virial mass means. Seems to give an estimate of 10¹² M☉.Rip-Saw (talk) 00:30, 20 March 2010 (UTC)

Milky Way avoids Serpens?

The list of constellations that the band of the Milky Way passes through includes Aquila, Ophiuchus, Scutum, and Sagittarius. I don't see how it could possibly avoid going through Serpens Cauda - is Serpens missing, or was Ophiuchus a mistake? DenisMoskowitz (talk) 14:13, 2 June 2010 (UTC)

Misuse of sources

Jagged 85 (talk · contribs) is one of the main contributors to Wikipedia (over 67,000 edits, he's ranked 198 in the number of edits), and practically all of his edits have to do with Islamic science, technology and philosophy. This editor has persistently misused sources here over several years. This editor's contributions are always well provided with citations, but examination of these sources often reveals either a blatant misrepresentation of those sources or a selective interpretation, going beyond any reasonable interpretation of the authors' intent. Please see: Wikipedia:Requests_for_comment/Jagged_85. I searched the page history, and found 4 edits by Jagged 85 in May 2008 and 3 more edits in July 2008. Tobby72 (talk) 21:54, 11 June 2010 (UTC)

I'm working on addressing this. Viriditas (talk) 22:26, 23 February 2011 (UTC)

Milky Way: [1][2][3][4]

The above line provides a summary of the edits made by Jagged 85 to this article (each diff shows the result of a sequence of edits). Johnuniq (talk) 00:01, 24 February 2011 (UTC)

What is Going to Happen in the Future to our Galaxy?

I heard our galaxy is going to collide with another galaxy. If someone can prove this is true, I think it'd be nice to put this in the article. --BrandiAlwaysSmiles (talk) 20:15, 7 April 2010 (UTC)

We could link to this article http://en.wikipedia.org/wiki/Andromeda%E2%80%93Milky_Way_collision from the Milky Way article. thx1138 (talk) 21:19, 7 April 2010 (UTC)

A mention that though the galaxies will 'collide', it will have very little effect on any given system, due to the vast amoutns of empty space. The interacting galaxy page shows this well, since the milky way seems to currently be 'colliding' (absorbing,etc.) with the two Magellanic Cloud dwarf galaxies. 74.132.249.206 (talk) 12:56, 9 August 2011 (UTC)

Number of planets in the Milky Way

I have seen the figure of 10¹² planets in the Milky Way, but I don't understand how this is computed. Thanks, Yann (talk) 13:32, 25 June 2010 (UTC)

I suspect that that number is found by assuming that there are about 10 planets around each of the approx. 10¹¹ stars in the Milky Way (that is, that every star has a planetary system like our own). I suspect that that estimate may be slightly optimistic, but early results from surveys for exoplanets indicate that there are multi-planet systems around other stars, and a minimum of something like 10-15% of stars in the solar neighborhood host at least one planet. James McBride (talk) 16:03, 25 June 2010 (UTC)

2,500 stars per light year cubed?

How many stars would you say were in a 1 light year volume on the mid arm of a galaxy? I know this would be a decimal, but could someone tell me? --90.218.231.57 (talk) 23:09, 15 July 2010 (UTC)

Number of planets in the Milky Way

Resolved

 – Estimated figure added. Viriditas (talk) 22:21, 23 February 2011 (UTC)

I failed to find an answer to that in this article. 88.88.126.66 (talk) 17:24, 16 October 2010 (UTC)

---o

You failed to find that answer because we have no clue. We have only recently been able to identify planets around stars, and of these most are Jupiter sized. So we have 8 planets (poor pluto) around our star and the Milky way is estimated between 100 - 400 billion stars. You can make a really really rough estimate with those numbers. -- TJ —Preceding unsigned comment added by Analystbynature (talk • contribs) 20:41, 16 October 2010 (UTC)

Hmm yes, an estimate would be hard I guess. But in the article about planets, it says 490 in the MW. 88.88.126.66 (talk) 11:42, 17 October 2010 (UTC)

That's 490 discovered planets, but as Analyst above says, there are probably billions of planets in the Milky way.--Roentgenium111 (talk) 22:57, 19 October 2010 (UTC)

if the estimative of super-earth planet are 30% http://www.scientificamerican.com/article.cfm?id=many-stars-may-have-super-earths (this talk only about super-earth then imagine earh-size mecury-size 95% if not all the stars have planets) and if each of this star have a least 5 planets,the milk way galaxy, should have a least 165-666 billions of planets by the estimative of 100-400 billions of stars of milk way the estimatives than i put here still low(because one star normaly have more than one planet,many stars have planets too small to be detect,ever by kepler,many of this star binary,but this star can have planets in wide orbit,many of this stars have short orbit alow the planet orbit both in circumbinary orbit,or each of the stars in the binary system can have planets orbit each one of the componets of the system,same for the multiple star systems ) ,the estimative of 50 billions planets it's too low.... —Preceding unsigned comment added by 189.83.23.148 (talk) 00:49, 15 May 2011 (UTC)

Minor suggestion for the text above the "Contents" box - Intro

In the introduction above the contents box there is a minor issue but I couldn't edit it.

It says in the first sentence; "The Milky Way Galaxy, commonly referred to as just the Milky Way, or sometimes simply as the Galaxy, is the galaxy in which the Solar System is located."

To clarify, it should say "in which our Solar System is located." There are other solar systems in the Milky Way and I believe this sentence is trying to indicate it is where our solar system is located. —Preceding unsigned comment added by Analystbynature (talk • contribs) 20:31, 16 October 2010 (UTC)

Designation?

Does the Milky Way have an astronomical designation? I've checked both lists on Wikipedia, neither the Messier list (no surprise there) nor the NGC contains it.--Amitakartok (talk) 00:37, 17 October 2010 (UTC)

I doubt it, because those designations are for objects you can see from the earth. You can't see the whole Milky Way from the earth since we're inside it, so it wouldn't have its own designation. thx1138 (talk) 23:22, 19 October 2010 (UTC)

Values for Milky Way thickness inconsistent

The observation table says that the Milky Way has a thickness of about 1,000 light years, but the section on "Size" says that the estimated value for the Milky Way's thickness is 12,000 light years, an order of magnitude greater. Is this inconsistency just caused by data coming from two different sources? Which one do I value as more accurate? And can this inconsistency be changed? 24.7.113.93 (talk) 03:54, 26 October 2010 (UTC)

• 12,000 refers to the gaseous disk — strictly speaking twice the scale height of free electrons in diffuse warm ionised medium (ref). I would assume 1,000 ly refers to the scale height of thin stellar disk. Thick stellar disk is kinematically and chemically a different component, and is—yes—thicker (scale height around 1 kpc, or 3 kly). The bar/bulge is thicker, too, perhaps 1 kpc. The shape of the Galaxy is a difficult topic, and will remain uncertain untill Gaia flies. Random astronomer (talk) 14:24, 2 November 2010 (UTC)

Please revert 2 edits by annon IP 16:35 UTC

Edits are hidden. My cellphone browser can't undo it. Thanks! निओ (talk) 17:42, 18 January 2011 (UTC)

Unsourced etymology

I've removed some unsourced material, which reads like a list dump. I would prefer to add a short summary of the list and mythology articles, but both are in poor shape and unsourced. The Harvard ref I've added properly summarizes the subject, so perhaps the section can be expanded from there. Removed material below: Viriditas (talk) 23:19, 23 February 2011 (UTC)

Slovene has a peculiar expression Rimska cesta (The Roman Road) for the Milky Way, which is not attested in any other language. The name is derived from an old notion that the pilgrims followed it when travelling to Rome.

In a large area from Central Asia to Africa, the name for the Milky Way is related to the word for "straw". This may have originated in ancient Armenian mythology, (Յարդ զողի Ճանապարհ hard goghi chanaparh, or "Trail of the Straw Thief"), and been carried abroad by Arabs. In several Uralic, Turkic languages, Finno-Ugric languages and in the Baltic languages the Milky Way is called the "Birds' Path" (Linnunrata in Finnish), since the route of the migratory birds appear to follow the Milky Way. (The Qi Xi legend celebrated in many Asian cultures references a seasonal bridge across the Milky Way formed by birds, usually magpies or crows.) The Chinese name "Silver River" (銀河) is used throughout East Asia, including Korea and Japan. An alternative name for the Milky Way in ancient China, especially in poems, is "Heavenly Han River"(天汉). In Japanese, "Silver River" (銀河 ginga) means galaxies in general and the Milky Way is called the "Silver River System" (銀河系 gingakei) or the "River of Heaven" (天の川 Amanokawa or Amanogawa). In some of the Iberian languages, the Milky Way's name translates as the "Road of Saint James" (e.g., in Spanish it is sometimes called "El camino de Santiago").

This is fine to remove, we have dedicated articles List of names for the Milky Way and Milky Way (mythology) where this information can go, if sources are found. Polyamorph (talk) 08:27, 24 February 2011 (UTC)

200 billion ≠ 1×10¹¹

 Number of stars	200–400 billion (1–4×1011)

200 billion is not equal to 1×10¹¹. The above should read: 200–400 billion (2–4×10¹¹) or 100–400 billion (1–4×10¹¹). Please correct me if I'm wrong. --George Makepeace (talk) 01:33, 25 February 2011 (UTC)

You are correct, the references cited say 200-400 billion so I have fixed the text. Polyamorph (talk) 10:38, 25 February 2011 (UTC)

Isn't 4×10¹¹ four houndred thousand million stars? 400 billion is 400,000,000,000,000 or 4×10¹⁴ — Preceding unsigned comment added by 188.80.245.124 (talk) 15:33, 7 December 2011 (UTC)

See Long and short scales. Thanks. Regards, RJH (talk) 16:58, 7 December 2011 (UTC)

View From Earth

The astrological direction of slow motion of the Center of the Milky Way is a good paragraph.

A way to visually understand galactic rotation is that the angle between the Andromeda Galaxy and the Center of the Milky Way is slowly increasing. At the present time the galactic longitude of Andromeda is 121.17 degrees. (Andromeda is about -20 degrees in galactic latitude and south of the galactic equator.) If the angle is watched carefully for a thousand years it should increase by six arc-seconds or so. In 35 million years it will be a radian, 57 degrees. Galactic coordinates behave like ecliptic coordinates - their zero slowly migrates around the sky. In the past several thousand years the Spring equinox migrated from Aries well into Pisces, at least thirty degrees.

Has anyone noticed that scientific authors tend to place the Earth and the Solar System above the Galactic center, rather than below it? Is there some disagreement on this matter? Which is the proper orientation? 173.53.79.191 (talk) 21:54, 20 March 2012 (UTC)

Age undue synthesis

The figures given in the section Milky_Way#Age is improperly referenced with references that claims "nothing of that kind!" The text claims that an age of 13.2 Ga for HE 1523-0901 gives a lower limit of the age of the MW. It of course does not. If f.ex. MW was formed by the merger of diverse dwarf galaxies, then HE 1523-0901 could have originated in one of those dwarf galaxies, to join the newly emerged MW at the creation year zero, while the HE-star itself was already say 3 Ga old. Rursus dixit. (^mbork³!) 13:58, 25 April 2011 (UTC)

space.com, tertiary source, claims 13.6±0.8 Ga. Using space.com or similar as a source is better, since then we're not doing the WP:SYNTH, just referring to a claim. Rursus dixit. (^mbork³!) 14:06, 25 April 2011 (UTC)

panorama desription

"Part of the Milky Way arches across this 360-degree panorama of the night sky above the Paranal platform, home of ESO’s Very Large Telescope. The image was made from 37 individual frames with a total exposure time of about 30 minutes, taken in the early morning hours. The Moon is just rising and the zodiacal light shines above it, while the Milky Way stretches across the sky opposite the observatory."

Is it nessasry to have all this infommation under the panorama? I think it could be cut down to "Part of the Milky Way arches across this 360-degree panorama of the night sky above the Paranal platform, home of ESO’s Very Large Telescope."
Let me know what you think
-Sic dicit Defectu tui omnis iam = So Says your failure is always present 15:17, 2 June 2011 (UTC)

Remark on page popularity

This article is currently ranked 17th on the list of the Wikipedia most popular astronomy article views, but it only has a 'B' rating. It might be worth bringing up to GA status. Regards, RJH (talk) 19:05, 12 August 2011 (UTC)

Introduction paragraph

The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

---

The introduction sentence of this article[20] fell short of WP:MOSBEGIN re:redundancy (galaxy) and going into linguistic descriptions instead of defining the subject. It is also redundant to say "home" "of the Solar System, and of Earth", if one is in the Milky Way then the other is as well. Also "home galaxy"?.... does the Solar System have another one when it is traveling?? The paragraph also contained a confusing/erroneous inline comment. "Solar System" does not necessarily "refer to the sun" re: Websters and NASA. Fountains of Bryn Mawr (talk) 15:20, 20 August 2011 (UTC)

It also says "our" Solar System... first person pronouns like that aren't supposed to be used on Wikipedia, are they?J'onn J'onzz (talk) 16:30, 25 August 2011 (UTC)

I assume your referring to WP:TONE. It recommends "common sense". And the spirit of the guideline seems to be WP:NPOV re: don't take sides. This is one case where we can use common sense and take a side....errr... we all live in this solar system ;). Referenced definitions of "Milky Way" seem to use "our solar system". We could always use the alternative wording "the Earth's solar system". Fountains of Bryn Mawr (talk) 21:28, 25 August 2011 (UTC)

I'm reverting to "the" Solar System. There is only one Solar System, i.e. the one centered on the sun (aka "sol"), and "our" should be excluded per WP:TONE. Dragons flight (talk) 03:27, 17 September 2011 (UTC)

PS. If you want to say "Earth's Solar System" "the Solar System and Earth" to make it clearer to naive readers, then I'm probably okay with that, but we should still avoid using first person. Dragons flight (talk) 03:29, 17 September 2011 (UTC)

"The solar system" is correct, as you say there is only one solar system. Polyamorph (talk) 06:29, 17 September 2011 (UTC)

(de-indent) I have changed it back to "our" solar system. This is a case of verifiability, not opinion. No reliable source has been put forward that there is "only one" thing that can be referred to as a "solar system" and reliable sources contradict that statement (Websters, NASA, simple Google book search "other solar systems" - 8,660 instances)

The statement "there is only one solar system" is akin to "there is only one galaxy", both of which used to be true. "Solar System" has gone on from its original "sol" roots a long time ago, the same way "Galaxy" has gone on from its original "sole universe" and "milk circle" roots, and referring to planets around other stars as "solar systems" is very common usage[21]. There are now (as of September 15th) 562 identified "solar systems" (and billions of possible ones in our galaxy alone) so there is a need to specify which one we are talking about.

WP:TONE does not excluded first/second person - it recommends "common sense" i.e. apply WP:NPOV to exclude statements that do not apply to everyone. This is a case where the statement "our" applies to everyone, we all live here, no exceptions.

Other variations?:

"Earth's Solar System" - its actually the Sun's solar system

"the Solar System and Earth" - redundant logical statement, if one is in the galaxy, the other is as well.

Fountains of Bryn Mawr (talk) 14:09, 19 September 2011 (UTC)

I disagree and don't think you should have reverted without discussing first. By your logic the featured article Solar system also needs to be changed, I can't see that happening. Polyamorph (talk) 14:37, 19 September 2011 (UTC)

The IAU uses "the Solar system" e.g. http://www.iau.org/public/naming/#outteruses . Sure there are some sources that use the incorrect terminology for other star systems but that doesn't mean we should make the same mistakes.Polyamorph (talk) 14:59, 19 September 2011 (UTC)

The IAU recommends that individual astronomical objects (such as the Earth or the Solar system) are capatalised, see here. So referring to the Solar system as a singular object is perfectly correct according to IAU nomenclature.Polyamorph (talk) 15:21, 19 September 2011 (UTC)

(posting after odd closure that seems to be based on (head count?[22]) WP:ROUGH CONSENSUS)

You seem to be confusing the concept of "the Solar System" (ours) with "a solar system" (composed of planets around other stars). Neither IAU or the Solar system articles take a stand on that nomenclature, other than that we live in a solar system and our Solar System is normally capitalised. No verification has been supplied for the statement "There is only one Solar System". You may have the opinion that "some sources" "use the incorrect terminology" but you need to cite more than your opinion. I am afraid you are pushing a river there called the English language. Wikipedia is an encyclopedia written in Plain English (WP:MOS). We have plain English guides called dictionaries, and they track word use for us, saving us from the problem of original research. The first reference note at Solar system contains the Merriam-Webster's 11th Collegiate Dictionary's entry on "solar system", re:

"the sun together with the group of celestial bodies that are held by its attraction and revolve around it; also : a similar system centered on another star."

It does not get any more reliable than that.

If you are still of the opinion that "There is only one Solar System" feel free to take a little time to prove it. Fountains of Bryn Mawr (talk) 22:19, 22 September 2011 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

picture taken in southern hemisphere please

someone please add a picture of the night sky taken from the southern hemisphere here, without the galaxy going off the horizon as it does in the north. Okay? — Preceding unsigned comment added by 75.87.138.107 (talk) 23:50, 2 September 2011 (UTC)

Age (again) link

These guys claims to have made an adjustion to the isochrones of stars due to debated gravitational settling (atomic diffusion) in the interior of old solar-type stars, and instead of the notorious 16-14 Gyr old age of Milky Way got 10-12 Gyr. In my opinion this only demonstrates that the concluded age of 13.6 (or so) Gyr is very insecure. Slight modifications of star models can cause vast variations in the age determination, and added to that, the age estimates varies also due to the asserted criteria for birth, whether it equals to the birth of the bulge and the globular clusters which might have occurred 2 Gyr before the birth of the disk and spiral arms... Rursus dixit. (^mbork³!) 15:37, 15 September 2011 (UTC)

Unverified statement

• The Milky Way has a relatively low surface brightness due to the interstellar medium that fills the galactic disk, which prevents us from seeing the bright galactic center.

The above statement is unverified and looks to be wrong since it seems to imply that removing the dust lanes would increase surface brightness. It wouldn't, the areas behind the dust lanes would be just as bright as the visible areas. I have seen statements in some texts that the galactic core would be a much brighter object if it was not obscured by dust lanes, but that is a different concept. Fountains of Bryn Mawr (talk) 16:27, 16 September 2011 (UTC)

Galactic centre distance and Galactic mass

I made a few alterations to the article, bringing the stated distance to the Galactic centre in line with more recent data and papers -- in particular removing references to Eisenhauer et al 2005 which has been superseded by Gillessen et al 2009 (identical data plus further observations, similar author list, systematic uncertainties better understood). I also added a more recent estimate of the total Galactic mass (based on many data sets, rather than just the one). — Preceding unsigned comment added by Trefusius (talk • contribs) 15:44, 16 November 2011 (UTC)

Supermassive black holes

There have been a few edits regarding the wording of this sentence: "Most normal galaxies are presumed to have supermassive black holes at their centers." I think that "presumed" is incorrect: this is an observation, not a presumption (or assumption). The first sentence of the abstract of the cited paper says "Beyond all reasonable doubt, black holes are commonly found in the nuclei of most normal galaxies."

Also, Supermassive_black_hole#Supermassive_black_hole_hypothesis (though not a reliable source, it was cited in this edit) says "Astronomers are confident that our own Milky Way galaxy has a supermassive black hole at its center, 26,000 light-years from the Solar System, in a region called Sagittarius A*[10] because:..."

Both statements are pretty unambiguous; all the evidence points to the presence of a supermassive black hole at the center of the Milky Way and most normal galaxies. I think that words like "presumed" weasel inappropriately. Obviously, nothing is universal, hence the qualifiers "most" and "normal".

Thoughts? (Commenting here rather than edit warring.) —Alex (ASHill | talk | contribs) 02:31, 31 January 2012 (UTC)

Commenting since I did the edit. "Sagittarius A*... is a supermassive black hole" and "Most normal galaxies have supermassive black holes at their centers" are absolute statements[23]. "Beyond all reasonable doubt" and "Astronomers are confident" are not absolute statements. One cannot become the other per WP:V. Things can be de-weaseled but they cannot be converted into absolutes to do that. Fountains of Bryn Mawr (talk) 03:23, 31 January 2012 (UTC)

I edited the paragraph again; I hope this sticks to the facts without inserting the sentiment "presumed" that is not in the referenced works. —Alex (ASHill | talk | contribs) 03:31, 31 January 2012 (UTC)

Reworded a little more to remove an absolute statement. Theoretical physics is by definition theoretical, as are black holes. Not sure if you are trying to apply WP:WEASEL but expressing theories in some form is not "weasel-y". "Presumed" is "suppose that something is the case on the basis of probability"[24]: we have referenced probability so "presumed" is not a weasel word. Fountains of Bryn Mawr (talk) 15:49, 31 January 2012 (UTC)

"Presumed" is an informal assessment by somebody, so to me is bordering on weasel. "Observed" does not require direct observation. See neutrinos for example. Regards, RJH (talk) 17:07, 31 January 2012 (UTC)

The statement "Supermassive black holes are located near the center of most normal galaxies" is incorrect per WP:NOR re: going beyond what is expressed in the source. The wording "Beyond all reasonable doubt" in the paper cited, and what is found in secondary sources re: "we now believe to be" (The Galactic Supermassive Black Hole - Forward[25]) "expected to exist" (Introduction to Black Hole Physics, page 11[26]) does not become the statement "are". Feel free to reword. Fountains of Bryn Mawr (talk) 20:55, 31 January 2012 (UTC)

BTW WP:WEASEL only applies to unsupported attributions, we are talking about supported attributions here. Fountains of Bryn Mawr (talk) 21:11, 31 January 2012 (UTC)

Since we do know with reasonable certainty that there are supermassive concentrations at the cores of galaxies, even if we can not yet unarguably confirm that they are SMBHs, perhaps it would be better to say something like, "Compact, supermassive concentrations are located near the centers of most normal galaxies"? Regards, RJH (talk) 21:20, 31 January 2012 (UTC)

That's the sentiment I was trying to get across with my last edit to the page, which now says "The concentration of mass around Sagittarius A* is best explained as a supermassive black hole.[47][48][49] Supermassive black holes are located near the center of most normal galaxies.[50]." I don't think saying "concentration of mass" two sentences in a row is necessary, though, given that there's essentially no debate left in the literature (including the two cited ApJ papers, ref 48 and 49 as of now) about the existence of supermassive black holes. I think that some form of the verb "to be" is a better representation of phrases like "beyond all reasonable doubt" and "it is known" than some form of the verb "presumed". —Alex (ASHill | talk | contribs) 22:41, 31 January 2012 (UTC)

It seems to my eyes that fewer new papers on super massive black holes are using the sort of "beyond all reasonable doubt" language that was once more common. For one example, see the intro or abstract of this paper about a cloud of gas on the way towards Sgr A*, which opens with "The Galactic center is one of the most extreme and puzzling places of the Milky Way. Harboring a supermassive black hole (SMBH) with a mass of MBH = 4.31e6 M_\sun� ..." Or, for SMBHs more generally, this paper about simulations of super star clusters around SMBHs opens with "It is known, nowadays, that many galaxies harbor a supermassive black hole (SBH) in their innermost regions." These are just a couple of recent sources that suggest that "presumed" or comparable language is unnecessary. James McBride (talk) 21:44, 31 January 2012 (UTC)

(de-indent) The papers have a context, that context being theoretical physics i.e we are still dealing with theories, not facts. Even the last papers quoted have phrases like "agree well with models" "mimics the situation observed". Its not our job to weigh the numbers of papers or jump to conclusions in any one sentence, but to match secondary sources (provided). Fountains of Bryn Mawr (talk) 14:43, 1 February 2012 (UTC)

Misuse of sources

Jagged 85 (talk · contribs) is one of the main contributors to Wikipedia (over 67,000 edits, he's ranked 198 in the number of edits), and practically all of his edits have to do with Islamic science, technology and philosophy. This editor has persistently misused sources here over several years. This editor's contributions are always well provided with citations, but examination of these sources often reveals either a blatant misrepresentation of those sources or a selective interpretation, going beyond any reasonable interpretation of the authors' intent. Please see: Wikipedia:Requests_for_comment/Jagged_85. I searched the page history, and found 4 edits by Jagged 85 in May 2008 and 3 more edits in July 2008. Tobby72 (talk) 21:54, 11 June 2010 (UTC)

I'm working on addressing this. Viriditas (talk) 22:26, 23 February 2011 (UTC)

Milky Way: [1][2][3][4]

The above line provides a summary of the edits made by Jagged 85 to this article (each diff shows the result of a sequence of edits). Johnuniq (talk) 00:01, 24 February 2011 (UTC)

(brought forward from Archive 3). Did this get fully addressed in February 2011? I note that the tag questioning sources dated September 2010 is still present. It's not trivial to address this issue, but it should be done. If it has been addressed, obviously the tag should go. —Alex (ASHill | talk | contribs) 23:43, 9 February 2012 (UTC)

Not addressed. Thanks for reviving this thread. Viriditas (talk) 12:22, 12 February 2012 (UTC)

I checked the references I could easily get my hands on (ie without doing anything drastic like going to a library or leaving my living room chair). I found only very minor issues; certainly nothing that makes me suspect going beyond what the sources claim. I left two flags in: one for a book that I could not find electronically (Mohamed, Mohaini (2000). Great Muslim Mathematicians. Penerbit UTM. pp. 49–50. ISBN 9835201579.) and a reliable source flag for this link, which does support the content in the article and is probably fine but is not published: Abu Rayhan Muhammad ibn Ahmad al-Biruni.

I didn't read all of the sources carefully; if anyone wants to do a more detailed check, this version of the article specifically flags the citations added by User:Jagged 85. —Alex (ASHill | talk | contribs) 05:57, 19 February 2012 (UTC)

External links

Please, could someone trim this back. It's unnecessary. Viriditas (talk) 12:20, 12 February 2012 (UTC)

Rather arbitrary amputation done. Replace anything essential with valid rationale. Vsmith (talk) 15:56, 12 February 2012 (UTC)

Which one?

"The Milky Way is the galaxy that contains the Solar System" which solar system is it talking about? — Preceding unsigned comment added by 67.219.227.73 (talk) 06:23, 15 February 2012 (UTC)

Was brought up before (above Talk:Milky Way#Introduction paragraph) and despite claims of nomenclature for "the Solar System" no such nomenclature was ever cited. Merriam-Webster answers the question, "our Solar System" [27]. If we all went to school in Ohio how would the teacher describe Ohio?:

• Ohio is the state that contains the the school .... current wording... pretty bad...
• Ohio is the state that contains our school ...technically true.....
• Ohio is the state in which we live ......
• Fountains of Bryn Mawr (talk) 17:22, 24 February 2012 (UTC)

I do not have a citation describing usage. Experience tells me that "the Solar System" refers to the Sun and the bodies in orbit around it. A literature search supports this. I looked through this list of 200 recent articles that include the words "solar system", and I counted one use of "solar system" to describe stars other than the Sun, and in that case, it was "Extreme Solar Systems". The Solar System is constantly used in reference to our Solar System, and I cannot find an example of "the Solar System" or "the solar system" being used to describe any other stellar system. James McBride (talk) 17:44, 24 February 2012 (UTC)

By the way, an analogy might be found with "Earths". The Kepler Mission's goal of finding habitable planets is often stated as "finding Earths" around other stars. Or, on their mission page, they say "Kepler looks at more than 100,000 stars so that if Earths are rare..." (Kepler: About the Mission). James McBride (talk) 17:54, 24 February 2012 (UTC)

The question is "what is common usage"? If more than on thing is called "solar system" then we have to specify. And we do have other things being called "solar system" IAU[28], NASA[29]. We don't do the original research to find word usage... dictionaries do. So a hard citation describing usage would be needed for the wording "the solar system". Fountains of Bryn Mawr (talk) 18:57, 24 February 2012 (UTC)

You did not seem to fully read my comment. The use of "the" is key. The Solar System. There is usage of "solar system" to describe other stars, but you have not provided evidence that "the Solar System" describes anything but the Sun and the bodies in orbit about it. James McBride (talk) 19:25, 24 February 2012 (UTC)

I should elaborate. Your citation of Merriam Webster does not actually include "the", and so is not a relevant "hard citation" describing usage. Moreover, I can just as easily cite dictionary.com, which makes no mention of other solar systems. James McBride (talk) 19:35, 24 February 2012 (UTC)

The New Oxford American Dictionary says simply "the collection of eight planets and their moons in orbit around the sun, together with smaller bodies in the form of asteroids, meteoroids, and comets." I agree that interpreting the phrase "the Solar System" (wikilinked to Solar System in case there's any ambiguity) is perfectly clear, correct, and unambiguous. However, what about saying "Earth" instead of "the Solar System"? Fundamentally, the Milky Way is more important to us than any other single galaxy because Earth is in it more than because the Solar System is in it. The inclusion of this detail is only useful for readers who don't know much about astronomy, and those readers may not know that we live in the Solar System but almost certainly know that we live on Earth. —Alex (ASHill | talk | contribs) 19:35, 24 February 2012 (UTC)

Re: providing "evidence that "the Solar System" describes anything but the Sun and the bodies in orbit about it"...per WP:BURDEN its not my job ... (no one can prove a negative) you have to prove it only has that use, its not up to me to disprove it. Dictionary.com link contains both descriptions. Re: Wikilinking to clear up ambiguity is not preferred - the meaning should be apparent in the sentence, a reader should not have to follow a link to understand a sentence (WP:BUILD). Re: switch to "Earth"... Ohio is the state that contains our room? Fountains of Bryn Mawr (talk) 22:43, 24 February 2012 (UTC)

It seems to me that you have the burden exactly backwards. All you need is a single example of a reputable source saying "the Solar System" to mean something other than our Solar System. Meanwhile, you think I should provide evidence that it is never used to mean anything other than our Solar System. James McBride (talk) 23:05, 24 February 2012 (UTC)

Again you are asking for a negative to be proven.... impossible... and against policy.... probably non-existant... and pointless. Even if some document existed re:"the Solar System" has only one technical meaning it would be of no use since it is not understood by a general audience (WP:TECHNICAL). Websters tracks the general audience meaning of terms... and they show "solar system" means more than "our solar system", causing the OPs question "Which one"? Fountains of Bryn Mawr (talk) 23:34, 24 February 2012 (UTC)

I asked you to find a single instance of "the Solar System" being used to mean something other than our Solar System. That is not asking you to prove a negative, no matter how many times you say it is. Moreover, you still fail to recognize that there is a distinction between "solar systems" and "the Solar System", just as there is a distinction between "earths" and "Earth, "Jupiters" and "Jupiter", etc. Anyway, I am done discussing this, as this is not accomplishing anything. James McBride (talk) 23:49, 24 February 2012 (UTC)

Huh? You haven't cited a source that says "the Solar System" can mean anything but the Solar System we live in. You also haven't cited a source that says "Solar System" (not "solar system") can mean anything but the Solar System we live in. Even if you did, when sources conflict, it's the most common usage that matters, not if you can find one source that supports your argument (though I still don't believe you have done even that). I'm unclear to which part of WP:BURDEN you're referring.

I think the Ohio analogy is completely misplaced (and is only relevant if there's only one "the Solar System" anyway). What is your alternate proposed wording? "Earth's Solar System", which you proposed in the closed discussion above, is considerably worse, IMO; to use your analogy, that's "Elyria's Ohio" (if we lived in Elyria, Ohio). The reason the Milky Way is interesting is precisely the fact that we (and Earth, and the Solar System, and the Sun, and the Solar Moving Group, and the Local Arm) are inside it, and that's worth saying explicitly, right up front, as briefly and clearly as possible. I've been bold and made that change; if anyone has a better suggestion, go for it. If no one has a better suggestion, we're just talking to walls. —Alex (ASHill | talk | contribs) 00:32, 25 February 2012 (UTC)

(de-indent) Hunting down "instances" of use is WP:OR. "common usage" has already been cited, by the only sources that can give you that. Sorry... we can only prove statements here, not negatives. So the statement that "there is only one solar system" or "the solar system" only has one correct use has to be proven, not dis-proven. The current wording looks fine to me. Fountains of Bryn Mawr (talk) 13:55, 25 February 2012 (UTC)

Individually resolved

This shocked me: All the stars that can be seen in the night sky are part of the Milky Way galaxy. Another page tells me that Andromeda is one of the brighter Messier objects and can be seen with the unaided eye. Presumably all the light emanating from Andromeda is star light. So, there are points of light in the heavens which we mistake for stars, which are not part of the Milky Way. Corollary: some of the light we can see with the unaided eye is older than the diameter of the Milky Way. The original wording would make one think otherwise until a "huh" moment later on. — MaxEnt 10:05, 24 February 2012 (UTC)

"Star" means Star, there are allot of things people mistake for stars but we can't take that into account. Also "individually resolved" has to be defined "with what"? Any object can be classified as individually resolved if the equipment used is unlimited (the Andromeda Galaxy can be/was individually resolved with a 100 inch telescope and a photographic plate). I reworded some of the tortured writing in the sentence (mostly my own). Fountains of Bryn Mawr (talk) 16:35, 24 February 2012 (UTC)

Formation

The article is completely missing an important topic: the formation of the Milky Way. I've taken a stab at a structure which I believe can be effectively expanded to do this by making the Age section a subsection of a new "Formation" subsection (as I think that "age" is most interesting to the extent that it tells us about the formation of the Milky Way, and "age" is meaningless without such a discussion anyway -- there wasn't a moment when the Milky Way came into being like there is for a person). Though the stub that I've put in needs to be expanded, I don't envision an enormous amount of content here; the details should be in Galaxy formation and evolution. —Alex (ASHill | talk | contribs) 01:16, 25 February 2012 (UTC)

Diagram of our location

The "diagram of our location in the observable Universe" image is squashed beyond recognition for me in both Safari and Chrome on a Mac. Is that just me? As it is, the image is useless, so I'll delete it unless it looks better in another browser. —Alex (ASHill | talk | contribs) 00:50, 11 April 2012 (UTC)

It just suddenly squashed itself. I use Firefox and it looks just as squashed there. Not sure what went wrong. Serendi^podous 13:38, 14 April 2012 (UTC)

It was because of a corrupted thumbnail. Ruslik_Zero 16:22, 14 April 2012 (UTC)

Much better. Thanks. —Alex (ASHill | talk | contribs) 00:02, 15 April 2012 (UTC)

WP:LDR?

Would anybody strenuously object if I apply WP:LDR to the citations in this article? In its current form the article is a little unwieldy and it should aid improvement efforts by moving the citations to their own section. As an example, WP:LDR is implemented on the Future of the Earth article. Thanks. Regards, RJH (talk) 19:01, 11 May 2012 (UTC)

I generally prefer that style and would love it if someone else were to put the work into it for this article! ;) —Alex (ASHill | talk | contribs) 02:55, 13 May 2012 (UTC)

Okay, thank you. I've only ever seen one person strenuously object to WP:LDR. Having used it for a while, I feel that the benefits (e.g. significantly uncluttering the article text) outweigh the drawbacks (e.g. having to do a whole-article edit to add citations). Regards, RJH (talk) 15:29, 14 May 2012 (UTC)

"shadow" of the galactic core is not a shadow

It is a total misnomer to label the region obscured by the galactic core a "shadow", as this is the direction where the greatest light of the galaxy is observed. Several Milky Way diagrams (including this current one from the article) are mis-labeled with that kind of wording. It would be a major improvement to switch this label to something like:

"region obscured by galactic core".

I expect that the motivation behind the "shadow" terminology was started because of the fact that there's a black hole at the center. However, even if this black hole were exposed, the extent of its "shadow" at most would be the diameter of its event horizon (and gravitational lensing would bend light near to that). However, the central black hole is not the reason why the opposite side of the galaxy is obscured. It's obscured by all the extremely bright stars that are gathered around that core. To call it a "shadow" is the exact opposite of what it is. I expect that fixing this mis-labeling on all of the Milky Way images will take collective effort.--Tdadamemd (talk) 01:06, 13 May 2012 (UTC)

I thought that the radio band was used to determine the shape of the Milky Way, rather than light. Regards, RJH (talk) 02:32, 13 May 2012 (UTC)

I see the original point as applying across the E-M spectrum, so I'm not sure I see what your distinction is advancing.--Tdadamemd (talk) 03:00, 13 May 2012 (UTC)

Well, conciseness. You specifically said light in italics. But no matter. I doubt that the black hole had anything to do with the "shadow" phrasing. Yes the phrasing is technically incorrect, but astronomy is full of peculiar terminology usage that comes from historical baggage. Take "early-type galaxy", for example, or "inferior galaxy". That being said, I'm not aware that "shadow" is commonly applied in this context. Regards, RJH (talk) 14:33, 13 May 2012 (UTC)

I was being very concise. The term I was objecting to, "shadow", refers to a lack of light. Whatever is beyond the galactic core is obscured by light, as well as radiation across the E-M spectrum. With all the feedback you've given, I still am not clear whether you are in support of this change or opposed to it. Yes, I'm well aware of how historical baggage gets carried down in science (like the convention of electrons having negative charge). But I'm not aware of any historical reason for calling this region in question a "shadow". In either case, I find it to be much smarter to weigh reason over tradition. Otherwise we'd still be calling Ceres and Pluto planets. Historical baggage runs the risk of painting you into a corner if not taken care of properly.--Tdadamemd (talk) 21:21, 13 May 2012 (UTC)

What change are you proposing? Please be bold; it's easier to discuss (and revert, if appropriate) an actual edit than an abstract one. The term "shadow" doesn't appear in the text, and "obscure" only in a completely inarguable context. The region obscured by the Galactic center region is a shadow at optical wavelengths, so the statement is true enough for an image label. Putting 5 words in an image label ruins the point of an image; that's what text is for. —Alex (ASHill | talk | contribs) 03:08, 13 May 2012 (UTC)

It is in various notations within images of the Milky Way, such as in the one I pointed to with the link in my first comments in starting this section. I don't have an .svg editor, or I'd make the change myself. I tried using the "easy" translator utility that Wikicommons provides, but it coughed up the new svg image when I tried to upload it as a replacement. I'm not a convert to svg yet. Some day I expect I will make the switch. I could easily convert the image to a .png or something to fix it that way, but I'm sure all the svg fans would not be thrilled by that approach.--Tdadamemd (talk) 04:05, 13 May 2012 (UTC)

Could you describe the change you're proposing (ie the text you want to replace and what you want to replace it with)? —Alex (ASHill | talk | contribs) 14:36, 13 May 2012 (UTC)

In the 'Spiral Arms' section of the article, it has this image:

That image at the bottom has this label: "Observation Shadow of GC".

What I've been saying here is that it is a misnomer to call it a shadow, as it is not. The proposal is to change the label to something like: "region obscured by galactic core"

It is analogous to the historical Planet Vulcan that had been theorized as being behind the Sun. You can't see what's back there because the Sun's light is obscuring that whole region. Now if you were to say that this hypothetical planet was in "the observation shadow of the Sun", then it would be a totally erroneous characterization. It is in the Sun's light. We can't see it because of the Sun's light. It is not a shadow at all.

Hopefully this will clear up whatever confusion had existed about the change being proposed here and why. The other point I made was that the problem is not limited to this article alone. The Commons has an entire category of "Milky Way maps" where there are other images that also call this region a shadow.--Tdadamemd (talk) 21:21, 13 May 2012 (UTC)

Thanks for clarifying. I disagree that that would be helpful in the image for the reasons I stated above. —Alex (ASHill | talk | contribs) 00:13, 14 May 2012 (UTC)

I'd be very interested to have your statement ("The region obscured by the Galactic center region is a shadow at optical wavelengths") explained to me, because that is the very thing I was objecting to. I don't see how a source of light can be considered to be casting a shadow. If the object that is blocking the light from whatever is behind it is producing its own light, then there is no shadow. You get more light.

Now if your point is that the light behind it is obscured, then it would be clear to me that "obscure" is the much more accurate description (as originally suggested).--Tdadamemd (talk) 04:53, 14 May 2012 (UTC)

If you want to say "obscured region", fine, whatever. I think it's perfectly clear what "shadow" means, and I always prefer using as few words as accurately conveys the message, particularly in an image label. The point of a sketch like this is that it should convey the point quickly and clearly, and the shadow we're talking about is far from the main point of this image anyway. —Alex (ASHill | talk | contribs) 12:17, 14 May 2012 (UTC)

I think this image is clear and concise, although I prefer the more-standard orientation of the one above. —Alex (ASHill | talk | contribs) 12:38, 14 May 2012 (UTC)

That's perfect! Thanks for finding that. I'd like to see that become the standard.--Tdadamemd (talk) 06:36, 15 May 2012 (UTC)

Unfortunately, this one is missing the outer arm, which is discussed in the text in reference to the figure, so the image would need to be edited to replace the existing one. I also think the inclusion of the H II regions helps, though it would help more if the caption referred to it. —Alex (ASHill | talk | contribs) 03:08, 17 May 2012 (UTC)

Here's what an "uncluttered" version of File:Milky Way Spiral Arm.svg looks like. Regards, RJH (talk) 17:44, 19 May 2012 (UTC)

Star chart?

Messier star chart

At present the article contains a surfeit of Milky Way photographs. However, what seems to be missing is a star chart like the one at right, but without the clutter of the Messier object information. I tried editing the image to remove the clutter, but at its base the SVG file is a bitmap where the messier object indicators are embedded in the core image. Does anybody have a suggestion for an alternative? I think it would be more informative to use a star chart than the long list of constellations in the Appearance section. Alternatively, the two can complement each other. Thanks. Regards, RJH (talk) 01:46, 17 May 2012 (UTC)

I agree. The paragraph listing the constellations really doesn't contribute much, but an image that does so in as uncluttered a fashion as possible would be great. I don't have a suggestion, alas.

Related, I agree that at least one of the five (!) visible-light panoramas of the Milky Way can be deleted. They're all pretty, but too many. I've gone ahead and deleted two that aren't really discussed in the text and therefore don't, I think, have encyclopedic value.

Also, there are two images that show the spiral structure of the Galaxy (the R. Hurt artist's conception and the schematic). I don't think both are necessary. I generally prefer the artist's conception. However, the labels in the artist's conception are illegibly small, and the schematic is referred to directly and moderately extensively in the text, so it can't be delated without a substantial edit. Perhaps delete the artist's conception and keep the version of it further down that shows Galactic longitude? —Alex (ASHill | talk | contribs) 02:56, 17 May 2012 (UTC)

The schematic diagram of the spiral structure does list the constellations through which the Milky Way passes fairly cleanly. However, I think that image is too cluttered for its main purpose (including as discussed in the previous talk thread). —Alex (ASHill | talk | contribs) 03:03, 17 May 2012 (UTC)

The concern I have there is that neither of the two images clearly communicates all of the information. The artist's concept is better at showing the dust lanes, while the schematic is good for its clear labeling. It's too bad we can't use the mouse-over image swap that's available with JavaScript. That way we could use a dynamic overlay. I suppose we could use an animated gif file. Regards, RJH (talk) 14:48, 17 May 2012 (UTC)

Please do not use an animated gif, they are soo distracting. When moving images are needed, a ogg file is preferred since it is a still image until the reader decides to show it. I (and probably very many more people) have a very hard time reding articles whit moving images. The User 567 (talk) 10:09, 18 May 2012 (UTC)

Okay. Regards, RJH (talk) 14:21, 18 May 2012 (UTC)

Hmm, we could overlay a transparent SVG version of the schematic on top of the artist's concept. Other options are to use an image map or the annotated image template. RJH (talk) 16:54, 17 May 2012 (UTC)

I have restored one deleted image, Milky Way.jpg. The section "Appearance" specifically needs a real world (showing the horizon) undistorted (shorter exposure, non-fisheye) image showing visual information "close to" actual "Appearance" (per WP:IMAGE). The fisheye Milky Way Arch.jpg image seems to also give visual information per how big the Milky Way is in the night sky, although fisheye shots can be harder to understand. Fountains of Bryn Mawr (talk) 21:26, 17 May 2012 (UTC)

Okay. WP:IDD may apply. Regards, RJH (talk) 22:25, 17 May 2012 (UTC)

I have restored Milky Way Arch.jpg. The "Appearance" section should answer two questions image wise:what does the Milk Way look like and how big is it? Milky Way.jpg and Milky Way Arch.jpg do this. Milky Way Arch.jpg is not a redundant version of Milkyway pan1.jpg since the first is a real world (including horizon) fisheye panorama image and the second is a constructed mosaic of the galaxy on axis showing a complete picture of it. The second seems to fit its section because it is a full picture ("composition"). I am not sure where WP:IDD applies, the only applicable points seem to be image overload or size. Size constraints are for images next to text (taged for "left" or "right"), not panoramas, and "overload would be that IMHO.Fountains of Bryn Mawr (talk) 19:58, 18 May 2012 (UTC)

It is redundant because it adds no new information that isn't present in the other images. Presenting as a fish-eye view is novel, but nothing more. Being a poorly stitched mosaic, it isn't even a particularly good image and it doesn't resemble how one would normally view the Milky Way. The multitude of other images already demonstrate the relative size of the Milky Way against the sky. The same information (and more) is available from the 360-degree panorama. Hence this image is clutter and adds a second broad (>220px) image. It is unnecessary IMO; one or the other of the two images in that section needs to go. I'll leave it there for the moment while it's being discussed. Regards, RJH (talk) 20:11, 18 May 2012 (UTC)

For the record, I agree that Milky Way Arch.jpg is not helpful; pretty, but doesn't add to the presentation. —Alex (ASHill | talk | contribs) 04:08, 19 May 2012 (UTC)

One factoid is "Something like 60 percent of the people in the United States have never seen the Milky Way", don't know what that is world wide. But that is what we are up against in an "Appearance" section. It needs to describe the Milky Way to someone who has never seen the Milky Way. Milky Way.jpg and Milky Way Arch.jpg do that because they have a (relatively) short exposure and throw in a horizon for reference. All the other images in this article (the ones that are not diagrams) are very bright exposures or false color, so have very little relationship to real world "Appearance". So the other images give you some "bright glowing thing" with no idea of relative size. Milkyway_pan1.jpg can not give the reader scale, no way to tell if that is the whole sky or just a .1 degree segment of some Hubble image. It is also a borderline poor image since it is only 700 pixels across, barely large enough to even tel you what it is trying to tell you. All of these images could be better, but I would replace them with better ones as the come along. Fountains of Bryn Mawr (talk) 12:46, 21 May 2012 (UTC)

Sorry but no. The first image is redundant with the header, which already shows a visual scale; the second image is redundant with the panorama from the "Size and composition" section. People don't have fish-eye vision and they can only clearly see part of the sky at a time, so the view is distorted, unrealistic and choppy. Even the image page description says it is "somehow distorted". It is far too bright compared to what the actual eye can see, so your statement about exposure seems incorrect. The image from Nevada has a weird green cast that is unrealistic. Regards, RJH (talk) 14:49, 21 May 2012 (UTC)

Like I said, none of them are perfect and they all have something odd about them for the reader who comes across this article (for example the lead image has the Milky Way being shot with a laser beam for some un-explained reason). In this example we tell the story with "visual information" and a "reasonable level of variety" (WP:IMAGE). New sub on the lead looks good BTW. Fountains of Bryn Mawr (talk) 16:12, 21 May 2012 (UTC)

Having "something odd" about all of the images is no reason to keep the patchwork fish-eye image nor the green horizon image. For example, the images below are all better quality fish-eye pics and communicate the same information without needing to take up the whole page width. Regards, RJH (talk) 17:10, 21 May 2012 (UTC)

• 
  Example
• 
  Example
• 
  Example

Re:should there be a star map? The list of constellations that contain the Milk Way is boarder line trivia and WP:NOTMANUAL IMHO. After many years of observing the night sky I personally don't know (and have never needed to know) what constellations those were. If you are at a basic knowledge level (the implied reader of this encyclopedia) it won't be useful (as in TMI), if you are advanced in your knowledge of the night sky you know how to pull out a star map to get this information. We could create a Commons category "Category:Star charts that contain the Milky Way" and put the link somewhere in the "Appearance" the section. Fountains of Bryn Mawr (talk) 19:58, 18 May 2012 (UTC)

Well, as an astrophysicist, who has used the Hubble Space Telescope and many others, I can say authoritatively that practicing astronomers are very aware of the constellations. Most of them do not need to "pull out a star map" to get this information. (If FOBM truly had "advanced knowledge" of the night sky, he would know the constellations too.) I would consider a list and/or map of the constellations in the Milky Way to be both appropriate and helpful for this article. I really like the "Messier Star Chart" shown above, and I propose that it be put into the article. 88.62.85.185 (talk) 05:56, 27 May 2012 (UTC)

Yes, as presented, the list of constellations is unhelpful. Regards, RJH (talk) 20:18, 18 May 2012 (UTC)

I've deleted the list of constellations. Should someone want to retrieve it, see the diff. —Alex (ASHill | talk | contribs) 00:26, 22 May 2012 (UTC)

Sentient species in the Milky Way galaxy (Mutter's Spiral)

How many sentient species are there in the Milky Way galaxy since there are 200 billion stars in there? Dantescifi —Preceding undated comment added 00:48, 1 July 2012 (UTC)

Around 12,000, according to astrobio.net. — Preceding unsigned comment added by 79.184.68.147 (talk) 13:40, 23 March 2013 (UTC)

Satellite galaxies

I came to this article looking for information about how many satellite galaxies the Milky Way has, and was surprised not to find any discussion of them at all. Eventually I noticed a few words in the lead section, linking to the article that answers my question; and there's also a navbar down at the bottom.

But I think there needs to be something in the body of the article. It should mention the Magellanic Clouds (and how they got his name when they were visible in prehistoric times), it should say when other satellite galaxies were discovered, and it should talk about how many there are, what the range of sizes and distances is, and any uncertainty in those numbers. I figure a couple of hundred words should do it, together with a repeat of the link that's in the lead section.

--142.205.241.254 (talk) 22:53, 12 July 2012 (UTC)

Yes, I agree this would be a good idea indeed. Anyone is welcome to begin doing this. Casliber (talk · contribs) 23:42, 12 July 2012 (UTC)

Isn't this the environment section of this article, which talks about the Local Group? —Alex (ASHill | talk | contribs) 00:14, 13 July 2012 (UTC)

Hubble sequence type wrong?

The article lists the Milky Way as Hubble sequence type SBc, citing a paper posted on the arxiv in 2002. But:

• The article says the best evidence for the galaxy's shape was found in 2005.

• The Hubble_sequence article says: "Our own Milky Way is generally classed as SBb, making it a barred spiral with well-defined arms. However, this classification is somewhat uncertain since we can only infer how our galaxy would appear to an outside observer."

• SBc looks rather extremely shaped to me (a non-expert), inconsistent with the "artist's conception" pictures here.

Can someone find current sources to resolve this? — Preceding unsigned comment added by 65.127.215.157 (talk) 04:22, 17 July 2012 (UTC)

Also, the cited arxiv paper says Sbc, not SBc. — Preceding unsigned comment added by 65.127.215.157 (talk) 05:03, 17 July 2012 (UTC)

Rotation period

I removed this sentence from the intro: "The rotation period of the Galaxy varies from the inner parts to the outer edge with a spiral pattern rotation period of once every 50 million years and a bar pattern rotation period 15–18 million years." A couple reasons:
1) It's misleading (bordering on incorrect) to the bar and spiral pattern speeds are the "rotation period". Nothing physically rotates at that speed; the period of the Sun's orbit, for example, is 200 Myr.
2) Explaining these subtleties is too much for the lede, particularly given that I don't see it mentioned at all in the text. Including these numbers in the infobox is useful, but I don't see the need to duplicate the information in prose in the lede. I think that expanding the discussion in the velocity section with this information, next to the rotation curve discussion, would make sense. (A new subsection or separate subsection for internal kinematics and rotation of the Milky Way may make sense too.) I'll try to take a stab at some point, but I'm traveling so it may be a few weeks. —Alex (ASHill | talk | contribs) 06:55, 19 July 2012 (UTC)

Re-added and expanded. Not "mentioned at all in the text" is an oversight, not a guide on how to write the rest of the article. The rotation of the Milky Way is a standard question[30] and should be answered in the lead and in the article body (if it is missed in the article that is where we have to expand). Info about rotation is scattered around the article and is given in a technical form. Infoboxes are an independent summary of a prose article, they do not replace lead summaries (infoboxes summarize articles, not the other way around).

The body of the article has problem re: explaining rotation:

• One short prose paragraph is not enough to explain rotation. Yes, it does need expanding.
• Referring the readers to a diagram is WP:TECHNICAL, going beyond a "general audience". It should all be explained in prose. The value "kpcs" is unexplained, linking abbreviations is unacceptable re:MOS:ABBR. Wikilinking is not a substitute for explaining a term in prose.
• There is a content fork between the prose and the diagram description re:":"Milky Way (decaying curve) is attributed to dark matter.[92]" and "The difference is due to dark matter or perhaps a modification of the law of gravity.[91][92][93]"
• differential rotation was missed in the article.

Fountains of Bryn Mawr (talk) 14:46, 19 July 2012 (UTC)

My point (which I think we agree on) was that there should be more in the body and that detail should be added there; the minimal bit about rotation that's in the article body is just jargon. The newly added text is better and more useful than the jargon about pattern speeds that had been in the lede before. I agree that the infobox should summarise the article and that every number in the infobox should be described in the text; I don't think that every number in the infobox should be mentioned in the lede. —Alex (ASHill | talk | contribs) 15:52, 19 July 2012 (UTC)