Two Types of Bewildering Sunset Mirages
October 26, 2022
Photographer: Mila Zinkova
Summary Author: Mila Zinkova
Have you ever seen a sun that just doesn’t want to set? Well, on September 4, 2022, I did, over the Pacific Ocean near San Francisco. Of course, the sun set at the time it should have. I was watching miraged images of the sun and, believe me, this miraged sun was in no hurry to set. A few times, miraged images of the sun appeared at the same level they disappeared from a few minutes before, giving an appearance of the rising, rather than the setting sun. And then, for a few minutes the miraged sun hardly changed or moved at all. It was as if the world suddenly stood still. Actually, I was observing a beautiful Novaya Zemlya sunset mirage. The photo at top is a screenshot from a video I filmed. Click here to see it.
On the very next day, September 5, 2022, during a heat wave in California, I filmed another confounding sunset mirage (bottom photo). Click here to see the video. The atmospheric optics are quite complex. Because sometimes the density differences of the air are so great, rays become almost trapped within the air layers. This is referred to as ducting. It may take some time and large distances before the rays can escape these layers. Dr. Andrew Young helped interpret this odd sunset.
"It starts out looking like a fairly typical leaky-duct sunset, with a moderate amount of wave modulation within the duct (inversion layer). But then at the end, you do indeed have a blank strip that fails to close up; the Sun simply fades away in the extinction (loss of light in the atmosphere)."
In the video, you'll notice a green-flash bit or two in the early part of the display, before the Sun dips down into the really thick part of the extinction.
Dr. Young continues, "As always in these extreme Type B sunsets, the path length of the rays through the air becomes longer and longer as the Sun's geometric position goes farther below the astronomical horizon."
Mirages such as this can be confusing to try to understand, but they're a joy to behold.
San Francisco, California Coordinates: 37.7749, -122.4194
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