By Bob Berman
March 2, 2011

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.


The 2005 Old Farmer's Almanac


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Sailing from Hawaii to

Sailing from Hawaii to California I experienced a full arc moon bow. Very bright night. An amazing site. The dolphins following the boat were pretty nice also.

I was living on Oahu in

I was living on Oahu in Makiki on the 8th floor and I was looking west at the Downtown Honolulu city lights. We were sitting on the lanai having dinner and could see that it was raining down there, but when the Moon rose (which would have been to our backs) we saw an incredible specimen of a Moonbow. It was mostly purple but we could even see all of the other vivid colors of white, pink, green, purple and was A MAZE ING!

Thank you for asking this question, it brought back a wonder memory!

I had always wondered about

I had always wondered about this, and as I was riding over Rocky Mt. National Park on my way home to Grand Lake via motorcycle, about 9:30 PM, on a mid-August night in 1985, a rain blew in from the West and the full moon shined down from the East. A full Moonbow lit the park just below Fall River Pass. Incredible. There are no words to describle the beauty. About four cars had stopped to watch. I stayed until it faded and continused down the mountain. Once in the switchbacks, I rode into the rain and out of it again several times. I should be so fortunate to see another.

Moonbows are amazing. I

Moonbows are amazing. I observed one as a teen during a camping trip at Pohoiki, Hawaii, 1977. It was shimmery white and it extended over the entire bay, a complete moonbow. It was beautiful and it's memory has never left me.