Can a Sun Dog Appear Without Clouds?

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The discussion centers around the observation of sun dogs, which are bright spots that appear on either side of the sun, typically visible when ice crystals are present in the atmosphere. The original poster noted that they initially saw only one sun dog due to wispy clouds and questioned whether a cloud is necessary to see a sun dog. They referenced a Wikipedia article confirming that the visibility of sun dogs is indeed dependent on the presence of ice crystals, which are not always located between the viewer and the sun. Another participant shared a personal experience of witnessing a bright light near the sunset while driving, noting unusual weather conditions, including fog and unseasonably warm temperatures. This anecdote highlighted the intriguing atmospheric phenomena that can accompany sun dogs and other optical effects.
Jimmy Snyder
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I don't know what forum this belongs in. Move it at will. I have already posted this on the APOD discussion site.

Today on the way home from work, I saw a pair of sun dogs. At first I could only see the left one which was in a location where there were some wispy clouds. On the right, I could not see anything except a brightness that was more wishful thinking than sun dog. However, there were no clouds where that sun dog would be. Within 5 minutes, some wispy clouds appeared there and so did the sun dog. I assume therefore that you can't see the sun dog without the background cloud. Is this correct?
 
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cristo said:
The wikipedia article seems to suggest you are correct:
I had assumed that because sun dogs are symmetrically arrayed that the ice crystals were between me and the sun. Now that I think about it, that is not necessarily so. And according to the site, it is not so. That's why there must be a cloud for you to see the sun dog.
 
neutrino said:
If it helps...
It does. Thanks. It confirms that the location of the ice crystals is at the sun dog and not between the viewer and the sun as I had supposed.
 
wow..I saw something last night as well, driving home from work at about 6:10 pm. I was just south of Pearson airport headed west on the 401 in stop and go traffic. The sunset was beautiful. Just above and a little to the west of the sun was a verry bright light. I was looking at this for 10 minuits or so. I should have took a picture as i had a camera with me. Now the weather here was very strange yesterday. 10 or 12 degrees above normal. Very clear humid day, however there were fog patches all over the city all day yesterday. As I got west of Pearson I drove into a fog bank and for several seconds I could see this light shining thru the fog, even though the setting sun was blocked. I was going to post this last night but home life overtook me. Oh yea I did come out of the fog into the clear 10 miniuts later and the sun was down and the light was gone...spookey!
 
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