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Article contradicts itself on twilight definitions[edit]

Diagram shows twilight as...

Civil Twilight: Sun 0-6º below the horizon
Nautical Twilight: Sun 6-12º below the horizon
Astronomical Twilight: Sun 12-18º below the horizon

The text in the article shows twilight as...

Civil Twilight: Sun 0-6º below the horizon
Nautical Twilight: Sun 0-12º below the horizon
Astronomical Twilight: Sun 0-18º below the horizon

The diagram is right, not the text. See this article by Cambridge University. Appple (talk) 01:30, 20 August 2015 (UTC)
See Bowditch's The American Practical Navigator, pp. 227-228 & table 1516, which agrees with the definition as given in the text. AstroLynx (talk) 14:16, 11 August 2015 (UTC)
Further note that the Cambridge web article cited above does not cite a reliable source but only WP (circular reasoning). AstroLynx (talk) 14:20, 11 August 2015 (UTC)

The American Practical Navigator is a good source you have there. It's possible that it's right. It shows twilight as...

Civil Twilight: Center of sun 0º50' - 6º below the horizon
Nautical Twilight: Center of sun 0º50' - 12º below the horizon
Astronomical Twilight: Center of sun 0º50' - 18º below the horizon

However, the Glossary of Marine Navigation which is put out by the same agency says differently.

“ civil twilight. . 1. The period of incomplete darkness when the upper limb of the sun is below the visible horizon, and the center of the sun is not more than 6° below the celestial horizon.”

“ nautical twilight. . 1. The time of incomplete darkness which begins (morning) or ends (evening) when the center of the sun is 12° below the celestial horizon. The times of nautical twilight are tabulated in the nautical twilight are tabulated in the Nautical Almanac; at the times given the horizon is generally not visible and it is too dark for marine sextant observations. See also FIRST LIGHT.”

“ astronomical twilight. . 1. The period of incomplete darkness when the center of the sun is more than 12° but not more than 18° below the celestial horizon. SEE ALSO CIVIL TWILIGHT, NAUTICAL TWILIGHT.”Appple (talk) 01:30, 20 August 2015 (UTC)
Evidently, there is much confusion about the definitions (even among those who should know). Perhaps it is best to mention this in the article, the reader can then decide which definition s/he finds most practical. AstroLynx (talk) 11:21, 16 August 2015 (UTC)
That sounds like a good plan.Appple (talk) 01:30, 20 August 2015 (UTC)
@Appple please sign your postings by typing four tildes at the end so that I know to whom I am responding. AstroLynx (talk) 08:06, 17 August 2015 (UTC)
Article updated with both definitions. Appple (talk) 03:09, 20 August 2015 (UTC)
As I mentioned earlier, the Cambridge reference ("Ask an Astronomer") is not reliable as it refers to WP as source - so what you have here is circular reasoning. Either substitute it with an another verifiable source or leave it out all together. AstroLynx (talk) 07:48, 20 August 2015 (UTC)
In addition, the "Glossary of Marine Navigation" which you cite for the other definition of twilight is the appendix printed at the end of the "American Practical Navigator". Apparently, the authors of the glossary did not check their facts with the information in the earlier chapters of the manual. AstroLynx (talk) 07:59, 20 August 2015 (UTC)
@AstroLynx: Why haven't you removed or at least tagged the unreliable source(s)? Readers and editors should be made aware of the sourcing problems. --Florian Blaschke (talk) 15:25, 22 September 2015 (UTC)
I already mentioned in this section that some of the sources used by Appple were unreliable. In the mean time I have been looking at some other twilight-related sources but have not yet decided how best to correct the current text. Please feel free to do so yourself if you cannot wait. AstroLynx (talk) 15:35, 22 September 2015 (UTC)

Restore "In Religion" section[edit]

An argument could be made to restore the "In Religion" section. This section was here for a while with no problem, until I expanded the part about how twilight is used in Christianity. The whole section was then removed because "This is an encyclopedia article about the technical aspects of, and the defining "Twilight"." But, I would argue that a high level encyclopedia article is about the notion of a thing. Just like the article for the "Sun" has a religious aspects section, so too, the twilight article warrants one. It's simply further information related to twilight. The notion of twilight isn't limited to its technical aspects. — Preceding unsigned comment added by Matt1618 (talkcontribs) 18:03, 24 March 2016 (UTC)

  • Totally disagree. I was going to pull the religion section months ago, but have been busy with other projects. This article has slowly been turning into an excuse to pitch religious beliefs. Wikipedia educates the reader about science. Lots of things happen at twilight. We don't mention them all because this venue isn't the place for it, and there isn't enough gig space in the universe for all of it. The important things that do happen at twilight, other than plenty of folks sitting down for dinner, have their own articles. My suggestion is to go to the Christianity article, and write about Christian activities that occur during twilight. It will then be in the right place. Please don't take any of this personally my friend, but this isn't Bible class. It's Wikipedia. That section ABSOLUTELY does not belong in this article. This article is not the place for those preaching God, and that's just what that section was doing. This isn't the first article I've removed religious sales pitches from, and it won't be the last. Religious sections belong in religious articles. It would be like going to the Sun article, and mentioning that lots of people go to church when the sun is out. Then we will find in the the night article saying: "Lots of folks pray during the night". Also, you can't use the Sun article as a comparison, because the Sun was actually thought of "as a God" in ancient times, and that is the reference to it in the article. Apples and Oranges. Subject closed.-Pocketthis (talk) 18:29, 24 March 2016 (UTC)

I hear ya. I'm not a zealot or a fanatic or anything. I didn't intend to hijack the article for preaching purposes just to expand on how twilight is significant in the Christian arena. Wikipedia educates the reader "period" not just "about science." Going around taking out religious-related material seems a bit anti-religious. It's relevant information to the topic at-hand. Now, if it was blatant proselytizing, I would agree, that it's not proper. Perhaps there is a compromise? I could trim what I submitted to make it simpler, more directly related? I come with good will, with an open mind to your argument. But "subject closed" kinda shuts down the "Talk" doesn't it? Matt1618 (talk) 21:20, 24 March 2016 (UTC)

  • "Wiki educates people period" is the only thing we agree on. Thing is, Wiki educates people in the correct article. The article designed and created to educate the reader about the specific subject he is looking for. I wouldn't be going to the Christianity article to expand on the science of Twilight, just because I heard there was a paragraph there that dealt with what Christians do at twilight time. The subject is "CLOSED" because this is Wikipedia's protocol, and I've been helping enforce it for 5 years. You don't come with good will. You come with religion. You are a religious person. A person of faith. Please feel free to contribute to in the articles written by those who also live their lives on faith and not fact. No compromise. I'm sorry, take it where it will be appreciated. There isn't a religion in the world that doesn't have something going on at different times of the year, and all times of the day. Have fun writing about that in the articles designed to expand on them. Happy editing.Pocketthis (talk) 00:53, 25 March 2016 (UTC)

"You don't come with good will. You come with religion." Wow... so religious people are inherently ill-willed? I live by faith and fact. Faith and Reason are entirely compatible - but, this isn't the place for a discussion on that. I'm just sorry, as a relatively new contributor to wikipedia, to find people on here who squash relevant information just because it is religious in nature. "Articles must represent all significant views fairly, proportionately, and without bias." Matt1618 (talk) 06:15, 25 March 2016 (UTC)

And really all you had to say was, "Hey man, if you'd like to keep the 'In Religion' section, would you mind carving it out into a separate article? Then those who are interested can follow a link and those who aren't can ignore it" and I would have said, "Oh... yeah, sure, no problem." I'm creating a "Twilight (Religious use)" article now. Hopefully you won't mind my simply putting a link to it in the main article. Matt1618 (talk) 06:55, 25 March 2016 (UTC)

  • This isn't the front gate at someone's home where you can leave a Watchtower, and those that are interested can read it, and those that aren't can throw it away. This isn't the inside of someone's home where you can pop up on the TV screen begging for dollars, promising the sick, the old and the poor redemption, simply by sending in their life savings. The answer is no. No links. No Carving a new article. No. Take it to the Christianity article, and I'm sure you'll have no problem finding interested people to read your new section on how twilight is special for Christians during certain "Holy" times and activities. It's really simple: Think of the encyclopedia Science Articles as you would a Public School. You can't pray here. Now think of the religious articles as your church. Keep it where it belongs, and all is good. -Pocketthis (talk) 15:50, 25 March 2016 (UTC)
  • Comment - I think the issue is the sources, and not necessarily the content, although that most certainly needs to be reworded. Contrary to Pocketthis's inappropriate rant, if it's relevant to the article's subject and the sources support it being included, it should be included. Matt1618, do you have any other sources that might show it should be included? I don't think that much needs to be included, but I'm not going to dismiss it out of hand without seeing what's what. - Aoidh (talk) 16:26, 25 March 2016 (UTC)
As for removing the religion section completely, Pocketthis, you'll need a better reason than an anti-religion rant. - Aoidh (talk) 16:29, 25 March 2016 (UTC)
  • Baloney. Here is what he can do: If he thinks that he can write a religious twilight article that is "noteworthy", and an admin will approve it for publication after reviewing it, please be my guest and go for it. As far as inserting religious propaganda in this And as far as "My Rant": If it weren't for "rants" similar to mine, this place would be "Wikibible".Pocketthis (talk) 16:34, 25 March 2016 (UTC)
  • That's not how article creation works on Wikipedia. "Admin approval" is not part of the process, and this isn't some attack on Wikipedia. To use your public school analogy, while they don't sell people on religion in public school, they certainly learn the facts surrounding them, especially in classes like history where omitting such things would be a glaring omission. Stating facts about something isn't the same as pushing the idea of that thing. - Aoidh (talk) 16:50, 25 March 2016 (UTC)

I write articles. They are reviewed and approved. If not by an admin, perhaps by a reviewer. Until that article is reviewed and approved, it is in limbo. OK "Admin approval" technically is incorrect, but the approval fact isn't incorrect.-Pocketthis (talk) 17:08, 25 March 2016 (UTC)

  • OK then. A general statement that says in essence: Many religions view the twilight time of the day as holy, and many activities in various religions are practiced during that time. I'm fine with that. Pocketthis (talk) 17:00, 25 March 2016 (UTC)
I am totally with Pocketthis over this. If a paragraph says that the practitioners of religion X often roll in mud during twilight, then this is a statement about religion X, not about twilight, and belongs in the article about religion X, if there is one, and not in this twilight article. DOwenWilliams (talk) 19:21, 25 March 2016 (UTC)
It's a statement about both, actually. A section on why twilight is significant to a large group of people is absolutely relevant to the article. It makes no sense to say "If a paragraph says that the practitioners of religion X often roll in mud during twilight, then this is a statement about religion X, not about twilight." You're literally saying it's relevant to both, and then trying to suggest it's not relevant to the one you'd rather it not be on. - Aoidh (talk) 19:30, 25 March 2016 (UTC)
  • I know I promised I was done here, but after that last comment, I must reply: If we were in the religion X article, and rolling in the mud during Twilight time was mentioned, then twilight would be bracketed, and that would be that. It would not invite a section about religion X rolling in mud being placed in the Twilight article. If it did, then every bracketed word would be cross cut to a special section in the bracketed article. Also, lets look at it from what this site is based on: Noteworthiness. If a noteworthy celebrity likes to shower in the nude in his yard during twilight, does it get its own section in the twilight article, or would the word twilight just be bracketed in the noteworthy celebrity's article. The latter I'll assume, so, I must agree with D0wen here 100%. Pocketthis (talk) 20:30, 25 March 2016 (UTC)

Atmospheric refraction[edit]

I don't see any comments on atmospheric refraction.

Definitions and illustrations by illumination[edit]

I changed Definitions by illumination to the above, and added 4 shots of basically the same scene from two different angles; two at 200mm and two at 80mm, (1st and 3rd: 200mm, 2nd and 4th: 80mm) of our three time periods identified in this article, plus nightfall. That is four comparison shots to end all speculation about what each looks like. I moved around a couple of the other photos that were mislabeled, or in a place with no rationale for it being there. This is the first time since I have been playing in this article, that it makes logical, rational sense to me, with clearly visible comparison photos of each period. Hope you all feel the same way→ Pocketthis (talk) 17:35, 13 May 2017 (UTC)

Nautical Dawn[edit]

Are you sure that picture at the bottom with a lot of colors is nautical dawn? At nautical dawn the human eye finds it difficult, if not impossible, to discern traces of illumination near the sunset or sunrise point of the horizon as it says in the article. But in that picture it's extremely visible. Nautical dawn is the end of astronomical twilight so it is slightly distinguishable from night, the sky is very dark and that picture has a really bright sky with lots of colors. That picture is probably civil twilight so is too bright for even civil dawn. Showing this at nautical dawn or even civil dawn seems very misleading. This picture needs to be changed.Theultimateboss123 (talk) 21:00, 15 July 2017 (UTC)

  • I am fine with that photo being moved to the gallery, because the article was getting a bit crammed with photos. I just want you to know: Mr. Boss, lol...I don't agree with one word you said. It is astronomical dawn that is close to an evening sky, not nautical dawn. Nautical dawn is when the sky gives us the most contrasted and dramatic colors. In the morning, the Sun is rising, not setting, so as the earth rotates to reveal more sun, the sky becomes more illuminated every second. Near the end of nautical twilight, under the right atmospheric conditions, is when you will find your most colorful sky. Once we enter civil twilight, the colors begin to wash out until they are completely gone from lack of angle and increased brightness. In that sense, morning twilight, and evening twilight, are two varied and different light shows. Also, before moving a photo, you should click on it, and follow it to its origin in commons, where you would have discovered that approx: 15 countries in the world disagree with you completely, and use this photo as their nautical dawn photo. I'll be visiting Dawn to see what you did there as well. Thanks. Pocketthis (talk) 18:03, 16 July 2017 (UTC)
In my experience, nautical dawn, the beginning of morning nautical twilight, is easy to discern at the horizon in the direction of the sun, even when urban light pollution interferes with it. (Only in inner cities it may be difficult.) As nautical twilight progresses, it grows steadily brighter, and you find the sky to be colourful indeed. As nautical twilight ends and civil twilight begins, by civil dawn, it's already quite bright outside and you have no trouble orientating outdoors (unless it's really overcast, perhaps). Civil twilight is so bright that you would be hard-pressed to call it night. It's the nautical twilight phase that I'd describe as the true transition from night to day (or vice versa). In contrast, astronomical twilight is extremely faint except at the end, and I personally cannot discern its darker half (the first half in the morning) at all – the start of the second half (when the Sun is about 15 degrees below the horizon) is just barely discernible if there are clouds at the (northern, in my case) horizon to provide contrast, and only as nautical dawn approaches it finally becomes clearly visible. Astronomical dawn I cannot discern at all with the naked eye, but it sounds conceivable to me that in regions with no or very little light pollution this is different – I have yet to witness early dawn in such a region. It is probably telling that it is morning nautical twilight that is known as "first light" and evening nautical twilight that is called "nightfall", as that is when it gets truly obviously light or dark for the lay observer. This is also the high point of the so-called blue hour. --Florian Blaschke (talk) 15:00, 18 July 2017 (UTC)
  • Morning nautical twilight is sometimes referred to by photographers as "the Pink Hour". Both AM and PM nautical twilight periods are called: "Sweet light". Problem with capturing a morning nautical twilight shot under perfect conditions is, "you have to be awake, outside, and camera in hand" when everyone else is still sleeping. Thanks Pocketthis (talk) 17:00, 18 July 2017 (UTC)
Thank you, I hadn't heard of the expression "Pink Hour" before, but it reminds me of Homer's "rosy-fingered dawn". I'm a nocturnal person who tends to find broad daylight too bright, especially around noon, so twilight is my favourite time of day, along with the golden hour; when I can engage in free-running sleep, I often end up going to bed only in the morning. --Florian Blaschke (talk) 10:41, 20 July 2017 (UTC)
  • One of my best friends in Florida had the same affliction. He became the biggest owner of night clubs in Ft. Lauderdale, and remained the biggest for 40 years. He never went to bed until dawn. Today, he is 75, retired, and still hasn't really learned to fall asleep before dawn. When I flew to Florida last trip, I tried to teach him photography so he could cash in on his habits, but he never caught the bug, didn't have the eye, and that was that. Take care, and enjoy your beautiful city. Pocketthis (talk) 15:28, 20 July 2017 (UTC)