A circumzenithal arc appeared high over Hesketh Bank farmlands this afternoon.
The Circumzenithal arc is also know as the 'Upside down Rainbow', for obvious reasons.
This attractive phenomenon forms when sunlight refracts through horizontal ice crystals at such an angle that the light enters the crystal through its flat top face and exits through a side prism face, causing the distinctive upside-down rainbow effect. These arcs are linked to cirrus clouds. More data here...
They may occasionally be seen when sundogs are in the sky, yet can often be missed due to their high altitude.
See also...
Pat Regan ©
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