Talk:Sun dog

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Deleting reference to sunbows[edit]

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. Gpetty 15:37, 8 September 2007 (UTC)

Little Extra Explanation[edit]

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[edit]

"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 containsCCNs 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. - Gpetty 15:28, 8 September 2007 (UTC)

One word or two?[edit]

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...." — Franey 12:46, 24 August 2005 (UTC)

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).
Ideally the same form would be used throughout the article—and it is, apparently; unfortunately it is not the form used in the title. —Muke Tever talk (la.wiktionary) 01:29, 25 August 2005 (UTC)

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. --- Gpetty 19:19, 8 September 2007 (UTC)

Usage[edit]

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|Talk 01:38, 26 November 2005 (UTC)

I say "sun dog" and I'm British. Parhelion is more technical. William M. Connolley 21:10, 6 December 2005 (UTC)

The term (sundog) is used in Canada. Hu Gadarn

'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 (talkcontribs)

Aesthetic image added[edit]

I've added what I think is a beautiful picture of this phenomenon. I took it last year outside of New Ulm, MN. Axda0002 14:55, 16 May 2006 (UTC)

  • It's a wonderful photo. Thanks for uploading it. Seventypercent 04:19, 28 January 2007 (UTC)

Name?[edit]

Anyone know why it's called a sun "dog" ? 68.39.174.238 04:55, 15 December 2006 (UTC)

<proposal>The extra suns are "dogging" on the real one?</proposal>
/ Mats Halldin (talk) 11:09, 28 January 2007 (UTC)

Cleanup 2006-01-27[edit]

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)

Quad Solar Dogs[edit]

--70.126.236.103 10:31, 25 February 2007 (UTC)

Cool! Thank you for the link, I've added it to the article.
/ Mats Halldin (talk) 16:18, 25 February 2007 (UTC)

Edward IV[edit]

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.67.85.254.111 23:06, 4 July 2007 (UTC)

i.e. / e.g.[edit]

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? 212.84.102.228 18:01, 19 October 2007 (UTC)


I have a question[edit]

How often do sun dogs occur? —Preceding unsigned comment added by 76.245.122.120 (talk) 02:00, 9 August 2008 (UTC)

I do not believe they happen very often, but they do occur more commonly than moondogs. Saturday, January 30th 2009. 8:32 AM EST —Preceding unsigned comment added by 49ersfanforlife (talkcontribs) 13:31, 30 January 2010 (UTC)

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)

Clean up 18 July 09[edit]

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)

Nuremberg section[edit]

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)

I support this view, it clearly doesn't relate to the phenomenon covered by the article. I will move it to the UFO article. --79.168.10.241 (talk) 20:16, 8 November 2010 (UTC)
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)
This section is appears to be original research, and in violation of Wikipedia's NOR policy (http://en.wikipedia.org/wiki/Wikipedia:NOR). As already noted, it seems both questionable and otherwise unrelated to the articles subject, so I am commenting it out. RBarryYoung (talk) 17:03, 17 February 2012 (UTC)
Moved below. -- Beland (talk) 03:17, 3 June 2012 (UTC)

Removed text[edit]

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[edit]

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]

  1. ^ Link to Zurich Library digital archive (2 scanned pages)

Shackleton section[edit]

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)

Second image[edit]

The second image has no sundog in it, just a lens flare. It should be removed. 99.172.153.118 (talk) 21:06, 22 November 2011 (UTC)

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)
Well, even if there is a sundog, it isn't clear at all and is a pretty poor image of it. Not really helping people to understand what a sundog is. 99.172.153.118 (talk) 16:07, 23 November 2011 (UTC)
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)
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)
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)
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)
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)
Read Wikipedia:Uploading images too. Regards, nagualdesign (talk) 22:48, 13 December 2011 (UTC)

Today in Tucson[edit]

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 (talkcontribs) 17:32, 10 April 2012 (UTC)

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)

Sun dog vs fog/cloud bow[edit]

What's the precise difference between these? And glories too? Turkeyphant 20:48, 1 March 2013 (UTC)

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)

Proposal to change the title into plural "Sun dogs"[edit]

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)

  • Support. Good point, it would stop a lot of confusion. And for what it's worth, Google Ngram Viewer shows that the plural forms are much more prevalent. nagualdesign 17:55, 19 December 2014 (UTC)