Sundog and 22-degree halo

Friday evening right before sunset I took the dogs out to walk around the house. I looked up the street and thought I saw the sun through the clouds, but then I realized that it was actually a sundog, or parhelion. It was one of the brightest sundogs I have seen. There was about a half of the 22-degree halo, with a bright spot where the upper tangent arc would touch the halo.

sundog7feb14_2

Of course I didn’t have my camera, so I dragged the dogs back to the house and got it. In the couple of minutes it took to get the camera and get back out on the street, the sundog and halo were not quite as bright as they were before. Atmospheric displays like these can be short lived.

After I got the insurance shot, I walked up the street to try to get a view without the trees in the foreground.

sundog7feb14The 22-degree halo was strongest from the sundog up through the top of the arc, but I think there is a faint continuation clockwise in the second photo. There might have been a second sundog on the right, but, unfortunately, it was hidden from my vantage point. We don’t get good views of the sunset on our side of the mountain.

6 thoughts on “Sundog and 22-degree halo

  1. Cool! I had been watching for these since Robin began writing and photographing them. Just by coincidence, I saw the first last week driving in to work at 5pm. Two rainbow patches on either side of the sun, presumably at the 22 deg location, with the red band toward the sun. Cirrus clouds were scattered and I guess were crossing at just the right place.

    We don’t seem to get cirrus very often here, or if we do they’re obscured by cumulus.

  2. Wayne — Sundogs are actually pretty common, but you have to be looking at the right time and place. Since they occur when the sun is relatively near the horizon, it’s hard to see them if there are trees or buildings around. I probably see them most often when I’m driving, so I don’t get a chance to photograph them. If there are scattered clouds, they can come and go as you drive and the critical angle passes through the clouds.

  3. So good to see those sundogs there and that 22 degree halo. We see them pretty often here, but I always stop to appreciate them. A beautiful moment of atmospheric optics.

  4. Robin Andrea — As I mentioned to Wayne, they are pretty common here. You can see them in clouds other than cirrus if the conditions are just right. In fact I have seen a photograph of a sundog in a jet contrail. The geometry has to be just right.

  5. If sundogs or a halo were visible here near sunset on Friday I missed them, but a little earlier there was a great deal of rapidly shifting iridescence in the western sky. I was driving under the influence of clouds.

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