You've heard of “somewhere over the rainbow.” But how about “somewhere over the moonbow”?
A moonbow is a rare nighttime event. The Moon must be clearly visible in one part of the sky while rain falls in the opposite part.
Like a rainbow, a moonbow is an enormous arc in the sky but it is much less intense than a solar rainbow. It usually appears spooky white, although all of the spectral colors are present.
The size of the moonbow depends on the Moon's height: the lower the Moon, the bigger the moonbow. The tallest moonbows occur when the Moon is within an hour of rising or setting.
If you're a photographer, the colors of the moonbow will show up on high-speed film sufficiently exposed.