Can moonlight create rainbows?
Yes, the moon can create rainbows, but they are fairly rare. The conditions would be the same as for seeing an ordinary rainbow: rain drops in the air and a source of light — the sun or moon — shining on the rain from in back of you. Robert Greenler in Rainbows, Halos, and Glories says moon rainbows are usually reported as white, probably because when the light level is low, our eyes lose their color sensitivity. He gives a reference to a photo in Sky and Telescope magazine (59, 177 in 1980) that shows a lunar rainbow with the usual colors. But the photographer saw it as white.
