"I live in Kent, in the Southeast of England and so don't usually expect complexity in a halo display as the conditions are never quit right. Today, however, I was amazed and excited to photograph sundogs, a partial 22deg halo, an upper tangent arc, a Parry arc, circumzenithal arc and a partial supralateral arc. I've photographed all but the supralateral arc separately before but never all together! These photos were taken between 15.34 and 15.41UT but overall the display lasted for approx 20 minutes with the circumzenithal arc lasting the longest."
In the matching HaloSim ray tracing simulation. The sun was set to 21° high. 32% random oriented crystals produced the weak 22° halo, 35% columns made the upper tangent arc and 30% hexagonal plates the sundogs and circumzenithal arc. The finely etched Parry arc needed only 3% of its peculiarly oriented crystals.
If you have HaloSim installed, run the simulation yourself after downloading the simulation file kent.sim
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