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Recently someone added a sentence about "sunbows", which allegedly involve sunlight passing through "vapor or mist". This is (a) questionable, as I've never even heard the term "sunbow", in contrast to "glory", "fogbow", and similar well-known optical phenomena, (b) irrelevant to the present article, as it does not refer to the same phenomenon as "sundog", which invariably involves ice crystals and has a different appearance, and (c) technically incorrect, because "vapor" is a gas, invisible and has no optical consequences whatsoever. I'm therefore deleting the sentence in question.
Gpetty15:37, 8 September 2007 (UTC)reply
Little Extra Explanation
Snow is ice (if you compress snow without melting it will compact to ice as occurs often at the bottom part of a snow pack towards the end of winter), and super cooled water droplets do not necessarily turn to ice at 0 C. Since they are so small the probability of nucleation occuring in the droplet is also small so that they usually remain liquid well below freezing. Nearly pure bulk water freezes at around 0 C because a single nucleation event is highly probable somewhere in the water. Once there is an ice nuclei, it starts a domino effect where nearby water molecules accumulate around it and so on until the entire thing is frozen. You can prevent freezing in bulk water at 32 C by keeping the water in motion which often occurs in waterfalls and rapidly moving streams. For them to freeze the temperature usually has to be well below 15 F for quite a while.
I think the reason sundogs are more commonly seen during winter is because the sun sets earlier, it spends more time near the horizon (which is needed to see a sundog), skies tend to be less cloudy and hazy across large chunks of North America and Asia, and cirrus occur at lower levels, so they are more likely to be seen in front of a setting sun.
In light of this, I think that the page should be updated so that it does not claim that sundogs are winter phenomena.
Comment
"it is only produced in clouds cold enough to be ice rather than water, which only occurs far below 0°C."
I'm a little confused, there is no water below zero degrees. Water freezes (and turns to snow) at zero degrees, not far below. In fact most clouds that high are frozen, even in summer. Perhaps the author meant "cold enough to be ice rather than snow".
At any rate, Personal observations tells me that sun dogs only appear on very cold days.
(
William M. Connolley 09:51, 24 Feb 2005 (UTC)) Water clouds will remain super-cooled down to quite low temperatures. Absolutely pure water droplets won't spontaneously freeze until it gets to something like -40 oC (I forget the exact number). Air contains
CCNs so I think water droplets in the atmos tend to freeze at about -20 oC ish.
Almost correct: It's not CCNs (cloud condensation nuclei) that cause supercooled droplets to freeze, but rather so-called ice nuclei (IN), which can trigger ice formation at various temperatures depending on particle composition, size, etc. Usually IN won't cause a cloud to fully glaciate; therefore pure ice (cirriform) clouds are usually found only at temperatures colder than -40. Sundogs may occur in any weather, any season, as long at the clouds contain ice particles of the right shape. Note also that sundog is spelled as one word by most meteorologists. -
Gpetty15:28, 8 September 2007 (UTC)reply
One word or two?
Is it sun dog or sundog? The title uses one form, the first sentence the other. Should be consistent. If both forms are correct, the first sentence should give both, with the first form matching the article's title: e.g. " A sun dog (or sundog) is a relatively common...." —
Franey12:46, 24 August 2005 (UTC)reply
m-w.com gives 'sun dog', AHD gives 'sundog'; 'sundog' outnumbers 'sun dog' on Google. There is probably no standard form, so both could be "correct" (really though, "correct" is POV applied to English spelling: there are no regulating bodies, only established usage).
I would consider the American Meteorological Society's
Glossary of Meteorology to be the most authoritative reference; it uses "sundog", as do most meteorologists I know. If I knew how, I'd change the page title and have the alternate spelling redirect. ---
Gpetty19:19, 8 September 2007 (UTC)reply
I think it is one word really. I'll add though that I'd only ever heard the term 'Parhelion' previously. Sundog is new to me. I'm in ireland so perhaps reasonably the term 'sun angel ' is known
Dorkinglad (
talk)
21:06, 5 April 2019 (UTC)reply
Usage
Does anyone know how widely the word "sun dog" is used, less or more so than parhelion? I've not heard of either term, so I don't know if it's common in Britain, but it does sound like an Americanism. Any ideas on this, and also where & why the term originated? --
User talk:El Pollo Diablo|Talk01:38, 26 November 2005 (UTC)reply
'Sundog' doesn't quite capture the beauty of what's happening, I wish there was a nicer name for it. So I use parhelion —Preceding
unsigned comment added by
Drumnbach (
talk •
contribs)
Aesthetic image added
I've added what I think is a beautiful picture of this phenomenon. I took it last year outside of New Ulm, MN.
Axda000214:55, 16 May 2006 (UTC)reply
Not so much an alternative name as an attention-grabbing headline. The article itself properly refers to the phenomenon as sundogs and parhelia, along with the sentences, "Some even compared the phenomenon to the appearance of an angel." and "Megan Tenaya Birchell added: 'These are the kind of things that helps you understand people believing in angels'." Unfortunately the photograph (actually a video still) is copyrighted by Håkan Hammar, so we can't use it. Thanks for trying though. It must have been a slow news day too as this video was originally aired over a month ago. Oh how I love the Daily Fail. nagualdesign04:29, 3 January 2018 (UTC)reply
Cleanup 2006-01-27
I liked this article but felt it needed a better disposition, so I rearranged things quite a bit. Let me know what you think and, if I messed anything up, don't hesitate to revert it.
/
Mats Halldin (
talk)
11:01, 28 January 2007 (UTC)reply
Didn't Edward IV actually see a Parhelion at Mortimer's Cross? I believe there are actually documented sources. The War of the Roses by Alison Weir mentions it, but I don't know it's source.
67.85.254.11123:06, 4 July 2007 (UTC)reply
i.e. / e.g.
This article repeatedly uses 'e.g.' when 'i.e.' would be more correct (in that they are clarifications rather than examples). Does anyone object to changing this?
212.84.102.22818:01, 19 October 2007 (UTC)reply
If you look for them regularly at the right times it may surprise you how often they do occur. Look for small bright patches of light or colored rainbow-like patches the same distance from the horizon as the sun. Best chances when the sun is low in the sky and with some high clouds. Its not necessarily a winter phenomenon, but there are several factors that contribute to them being more likely observed in the winter months. I have seen two in the last couple months and maybe a dozen or so in my lifetime and thats without actually deliberately looking for them on a regular basis. However, I've never seen them extremely pronounced as in the couple of very bright ones imaged in this article. I'm assuming these are a more rare event.
Racerx11 (
talk)
03:01, 27 January 2011 (UTC)reply
Clean up 18 July 09
Tidied the technical section, removing several erroneous statements. Clarified their appearance, where they can be seen and how often. --
Halos25 (
talk)
16:11, 18 July 2009 (UTC)reply
Nuremberg section
I think we should delete this section. Perhaps the woodcut itself has cultural significance, but it belongs elsewhere. The first source cited in this section comes from a site about paranormal activity (at the bottom it says "Return to UFO Home" with an alien picture above it), and the second is in German. I can`t verify that this artwork really is a depiction of sundogs and halos, and I`m convinced that this is likely speculation.
SweetNightmares (
talk)
17:15, 19 August 2010 (UTC)reply
The UFO page is protected, so I restored the section even if it doesn't fit I share your view that it has significance enough not to be simply removed. --
79.168.10.241 (
talk)
20:20, 8 November 2010 (UTC)reply
News notice printed in Nuremberg, describing the celestial phenomenon of 4th April 1561 in
Nuremberg. From
Wickiana collection in Zurich Library.
Nuremberg, Germany in 1561
Sun dogs might explain a remarkable phenomenon observed in Germany: on April 4, 1561, the skies over
Nuremberg,
Germany were filled with a multitude of celestial objects that were observed by many people in the city. The phenomenon was described in a News notice (an early form of newspaper) published in Nuremberg on April 14, 1561, along with a woodcut by Hans Glaser, depicted to the right.[1]
I went ahead and removed the Shackleton section. The passage itself was not notable and as far as I can tell was just a routine description of the phenomenon. After looking at the article's history I see that this paragraph may have been useful at some point as part of a larger section of "quotations," but at this point it no longer serves the article.
Orange Suede Sofa (
talk)
02:51, 27 November 2010 (UTC)reply
It does look a little bit like a lens flare but there are subtle differences. Each 'spot' within a lens flare is
bokeh-like: a projection of the camera's aperture, with curved facets. The sun dog in the image has a smeared appearance above and below which follow a curve centered around the Sun. My guess would be that the photo was taken with a wide-angle lens, and the subsequent cropping has altered the relative positions of the Sun and sun dog and made them appear more flare-like. Regards,
nagualdesign (
talk)
23:38, 22 November 2011 (UTC)reply
It is a picture of a sun dog. That 'flare' to the left of the Sun is the sun dog. How could it be clearer? Perhaps you could find a better picture. ;-) The article explains what a sun dog is and the images show examples. Deleting or removing an image because you don't like or understand it will not improve Wikipedia.
nagualdesign (
talk)
21:20, 23 November 2011 (UTC)reply
I'm not going to remove an image because I don't like it or understand it. I just do not think it is necessary or a very good picture because an average person cannot distinguish it from the lens flare next to it. I have a great understanding of halos, and have many other pictures of ordinary sundogs that are much better than this one. I'm just worried it could confuse someone.
99.172.153.118 (
talk)
02:13, 28 November 2011 (UTC)reply
I you have another, possibly better image then I'd suggest that you
upload it. You are right that sometimes less is more, but we should always try to add value to an article. If other contributors believe that 2 images are better than one then it's good practise to offer an alternative image, rather than removing one. If your image(s) showed a pair of sun dogs, as is the norm, that might be an improvement.
nagualdesign (
talk)
04:23, 28 November 2011 (UTC)reply
How exactly do you upload an image on wikipedia? I do have plenty of images that are better, I think a image of an average sundog would be good, the others show exceptional cases.
99.172.153.118 (
talk)
21:21, 13 December 2011 (UTC)reply
Assuming that you've already tried the link I provided and perhaps didn't get the same page that I get, maybe you have to be a
registered user and sign-in before you can upload? Just a guess. You could try looking for more info at
Wikipedia:Upload and
Wikipedia:Picture tutorial. Also, when I'm signed in there's a link near the bottom of each image page that says Upload a new version of this file, but I only use that if I have a better copy of the same picture. I think new images should be uploaded separately. Hope that helps.
nagualdesign (
talk)
22:15, 13 December 2011 (UTC)reply
Every articles on sun dogs talks about ice. What about today in Tucson, a beautiful halo around the sun,
80 degrees? Could there really be ice up there, or maybe this isn't a sun dog. April 10, 2012. JDRIS — Preceding
unsigned comment added by
Jdris (
talk •
contribs)
17:32, 10 April 2012 (UTC)reply
Cirrus clouds (thin, wispy strands) vary in temperature from -20 °C (-4 °F) to -30 °C (-22 °F) and form at 4,000 m (13,000 ft) to 12,000 m (39,000 ft) above sea level. Even above Arizona the air gets pretty cold that high up - higher than the top of Mt. Everest! (
diagram) Besides, if you can see Sundogs close to the horizon from Tucson they're much further away than you might think.
nagualdesign (
talk)
19:53, 10 April 2012 (UTC)reply
You could have a look around
http://www.atoptics.co.uk for details. In short: sun dogs (and other ice halos) are caused by refraction in ice crystals. Fog/cloud bows and glories are all formed by liquid water droplets, of varying sizes. Large water drops form rainbows (opposite the Sun), while smaller ones tend to form fog bows, as diffractive effects starts to matter/dominate in smaller droplets. Glories and fog bows can occur together, with the glory typically being small, and the fog bow being roughly the same size as a rainbow.
Aeluwas (
talk)
21:59, 13 November 2014 (UTC)reply
Proposal to change the title into plural "Sun dogs"
Even though it appears very common among laypeople to refer to any ice halo phenomenon (especially the 22° halo) as "sun dog", the term only refers to either of the two spots to the left and right of the sun. Each of them is a separate sun dog; see
http://www.atoptics.co.uk/halo/parhelia.htm. For this reason I would propose to change the title of the page into the plural Sun Dogs (or Sundogs), and/or perhaps add a small section explaining the common misconception.
Drabkikker (
talk)
06:58, 19 December 2014 (UTC)reply
Splendid. There then; I took the liberty of adding section 2 'Terminology'. I think the most appropriate place is before 'Etymology', but feel free to edit, move or elaborate on the section. Oh, and merry Christmas to y'all!
Drabkikker (
talk)
10:51, 25 December 2014 (UTC)reply
Looks good. I moved the article. If anyone objects we can revert and discuss further. I also standardized the spelling as "sun dogs" (two words rather than one) across the whole article to be consistent with the spelling in the title. Interestingly, the OED spells it "sun-dog" but the Canadian OED uses "sun dog."
Meters (
talk)
18:11, 25 December 2014 (UTC)reply
Oppose. (See above) Fair point, but there are exceptions, including "articles on groups of distinct entities that are nevertheless often considered together. [..] In rare circumstances, we
ignore the rules here in order to make the encyclopedia better." (from
Wikipedia:Naming conventions (plurals)#Exceptions) Sun dogs generally form in pairs, whereas things that are often mistaken for sun dogs don't come in pairs. nagualdesign21:36, 26 December 2014 (UTC)reply
I don't think that applies, see "... preceded almost invariably by the word 'the')..." that you omitted. There aren't necessarily two sundogs visible. And it is different from scissors, glasses, pants, etc.
Bubba73You talkin' to me?08:36, 28 December 2014 (UTC)reply
The proposal to change the name was up for almost one week. Three people supported it and no-one opposed it, so I made a bold edit and changed it. I also clearly said that we could undo it and continue the discussion if someone objected. There's no need for the hyperbole that there was only one word or two on the subject.
Meters (
talk)
20:18, 28 December 2014 (UTC)reply
In Bubba's defense, there was no hyperbole. I believe he was referring to the section above titled
One word or two?, which dealt with a different issue. So
Bubba73, do you have any reason you'd like to change the title back? Perhaps you could state your reasons rather than asking if other people think the title should be changed, then we'd have something to discuss. Regards, nagualdesign22:32, 28 December 2014 (UTC)reply
Perhaps I misunderstood. If that was in relation to my decision to standardize the article to two words rather than one word, I simply went with the usage of the article title since the article text was more or less evenly split.
Meters (
talk)
22:50, 28 December 2014 (UTC)reply
It should be Sun Dog. A good test would be how you apply the indefinite article. You would say "this is a shoe", even though shoes almost invariably come in pairs. The exception is for where you wouldn't say for example "this is a Maxwell equation", you would say "this is one of Maxwell's equations". But you wouldn't say "that is one of a pair of Sun Dogs" or "that is one of the Sun Dogs", you would say "That is a Sun Dog".
Very well put. You've convinced me that I should not have moved it. I am in favour of moving it back to the original, singular title.
Meters (
talk)
19:37, 8 January 2015 (UTC)reply
I photographed a single sun dog on Dec 25 (left of the Sun). Today my daughter spotted a single one to the right of the Sun and I saw it too. The one on Dec 25 - a cold front was coming through and there were clouds to the left of the Sun (where the sun dog was) but not to the right. That might have something to do with seeing a single one.
Bubba73You talkin' to me?08:28, 10 January 2015 (UTC)reply
An argument in favour of using the plural is the common error (as a quick web search will show) of calling the
22° halo a "sun dog". Of course sun dogs can appear on their own if the ice crystals are distributed unequally across the sky, but their distinguishing feature is that they tend to come in pairs. Then again, so do
nostrils, so I can see your point.
Drabkikker (
talk)
15:42, 10 February 2015 (UTC)reply
Etymology.
I can recall, a long long time ago (as in like 50 years ago!), reading that it was called a "Sun Dog" because it follows close to the Sun like a deog does to its owner. It was so long ago that I cannot recall the source. — Preceding
unsigned comment added by
1.129.97.105 (
talk)
12:14, 20 May 2016 (UTC)reply