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Parhelic
Circle over the Dead Sea imaged
by Koby Harati ( Photography
site) on March 7, 2007. The camera is pointing straight upwards.
The white parhelic circle passes through the sun and circles around
sky, everywhere at the same altitude. The coloured halos
at top right are fragments of a 22
degree halo, circumscribed arc
and, on the parhelic circle, two sundogs.
Had
the sun been any higher the sundogs would not have formed. Image ©Koby
Harati, shown with permission. |
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The parhelic circle is a white band circling the sky and always at
the same height above the horizon as the sun. Most of the time
only fragments are seen, usually extending from sundogs in the directions
away from the sun. When you see these long tails it is worth checking
carefully all around the sky because the colourless parhelic circle
can at first be difficult to distinguish from cloud.
Millions of ice crystals with their
vertical faces each mirroring the sun around the sky form the circle.
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