There is a lunar rainbow - rainbow generated by the Moon Bashny.Net

Moon Rainbow relatively paler than usual. This is due to the fact that the moon produces (reflected from the Sun) less light than the sun. Moon Rainbow is always on the opposite side of the moon from the sky.

At night, under the moon light is too weak to excite the sensors in our eyes - cones, so that the color to see the lunar rainbow difficult. As a result of the lunar rainbow is usually seen as white. However, the photographs with long exposures may get colors.

Best of all lunar rainbow is visible when the moon is full, or the phase of the moon, near full, since at this time the moon is the brightest. For the appearance of the lunar rainbow, other than those caused by the waterfall, the moon must be low in the sky (less than 42 degrees and preferably even lower) and the sky must be dark. And of course, I have to go rain in front of the moon. This combination makes the necessary requirements of the lunar rainbow is much more rare than the rainbow, also appeared under the influence of rain, but generated by the sun.

Source: ru.wikipedia.org

via factroom.ru