Have you ever seen a halo around the Sun?

This fairly common sight occurs when high thin clouds containing millions of tiny
ice crystals cover much of the sky.

Each
ice crystal acts like a
miniature lens.

Because
most
of the crystals have a similar elongated
hexagonal
shape, light entering one crystal face and exiting
through the opposing face refracts 22
degrees,
which corresponds to the radius of the Sun halo.

A similar Moon halo
may be visible during the night.

Pictured above, a nearly complete
sun halo was photographed high above the ancient
Bayon temple in
Angkor,
Cambodia.

Exactly how
ice-crystals form in clouds remains under
investigation.

Related Skylook Posts:

• A Sun Halo Beyond Stockholm
• The Belt of Venus Over Mercedes Argentina
• Red Aurora Over Australia