A Lunar Corona over Paris

A Lunar Corona over Paris

Image Credit & Copyright:
Valter Binotto

Explanation:
Why does a cloudy moon sometimes appear colorful?

The effect, called a lunar
corona,
is created by the quantum mechanical
diffraction of light around individual, similarly-sized water droplets in an
intervening
but mostly-transparent cloud.

Since light of different colors has
different wavelengths,
each color diffracts differently.

Lunar coronae are one of the few
quantum mechanical color effects that can be
easily seen with the
unaided eye.

Solar coronae are also sometimes evident.

The featured image was taken last month from
Paris,
France.

The blue beacon emanating from the
Eiffel Tower
did not affect the
colorful lunar corona.