Why would a cloud appear to be different colors?
A relatively rare phenomenon known as
iridescent clouds can show unusual colors vividly or a whole spectrum of colors simultaneously.
are formed of small
droplets of nearly uniform size.
When the Sun is in the
right position and mostly hidden by thick clouds,
thinner clouds significantly
diffract sunlight in a nearly coherent manner, with
different colors being deflected by different amounts.
will come to the observer from slightly
Many clouds start with uniform regions that could show
quickly become too thick, too mixed,
or too far from the Sun to exhibit striking colors.
This iridescent cloud was photographed last year from the
Top of the World Highway outside
Dawson City, in the
Yukon Territory in Northern
Credit & Copyright:
Charles Stankievech & Sophie Springer