Sun Dog?

The photographs below were taken the evening of August 10th 2004 at Citadel Landing, on the banks of the Fraser River in Port Coquitlam BC. I have seen many varieties of sun dog before but this one caught my eye as one of the more beautiful. The evening was a very warm one with the temperature around the 25 C mark at 8:45 pm, when the first of these shots was taken. The last shot was taken about twenty minutes later. The view was to the north west. The sun itself was out of my line of sight, below the bottom edge in each shot. Photography was with a Canon S50 digital camera in automatic mode and magnification at 2-3x (optical).

I believe that the term "sun dog" refers to apparent images to the left and or right of the sun. Clearly that is not the case here. Perhaps someone knows of a better term. I'd be happy to hear alternatives.

Images may be clicked for an enlargement.


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Visitor postings

I am assuming that the sun position is below the colours shown.  To me it looks like the arc curves upward on the outer edges so I would choose the "Upper Tangent Arc" shown in the Halos link.  Or if the arc curves down how about we say it is part of the 22 degree halo and there were only ice crystals at that location of the sky. 
(Dan Phelps)

I saw this quite clearly on the evening of Tuesday August 10th The 22 degree arc (AKA the small halo) was clear and nearly completely surrounded the sun, with a brighter concentration at the top part of the ring (the bottom was not fully visible). This brighter region, giving the halo a "diamond ring" appearance, is probably a bit of the upper tangent arc or the Perry arc (two slightly different arcs that are roughly tangent to the upper (and in the case of the tangent arc, lower) part of the small halo.

Also visible were bits of the large halo, in the "sun dog" position and distinctly rainbow like. It was VERY neat! I regret not having a camera with me!

For information on such phenonena I highly recommend the delightful book Light and Color in the Outdoors by M.G.J. Minnaert. It is extremely thorough and well written, and more is one of those rare works that conveys the writers personality and fascination in a way that is individual, dynamic, and infectious (Barnham's Celestial Handbook is another of these, I think). 
(Philip Freeman)

Thank you for the link to the website that explained what I saw on the morning of August 9. So what did I see? I reckon a halo, parhelia, the upper tangent arc, and the parhelic circle. To see photos, go to <http://www.bennythecat.net/20040809/index.html>.
(Jim Scott)

Peter Vogel
Vancouver BC
 

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