Moon Ring | Hexagonal shape Ice crystal refraction Upper level atmosphere |
U
se whatever is available. Although I was thinking star trails, a cloud cover prevented their appearance. But the night was still interesting, offering up its own visual wonders, including this distinctive ring around the moon. Caused by the refraction of reflected sunlight off the moon by hexagonal ice crystals comprising cirrostratus clouds close to the thermal tropopause, this halo is 22 degrees across the sky. Substantial cirrus cloud presence sometimes indicates an approaching frontal system or upper air disturbance. This often signifies an imminent weather transformation strongly implying a pending storm.
“The night walked down the sky with the moon in her hand.” - Frederic Lawrence Knowles
