Is There Such a Thing as a Blue Moon?

The moon never changes its color, but there have been times when the moon did look blue to people on earth. In 1950, a huge forest fire in Canada sent tons of tiny cinders into the atmosphere.

These cinders absorbed some of the sun’s rays that bounce off the moon and reach earth, but didn’t absorb the blue rays. So for a few days after the fire, moonlight took on a bluish color, even for people thousands of miles away.

The moon has also looked blue after the eruption of powerful volcanoes, such as the 1883 eruption of Krakatoa in Indonesia, when tons of cinders were tossed into the air.