Yet it is called - a night rainbow.
This light reflected from the surface of the moon.
Compared to the solar rainbow, lunar dimmer, because the light is not so bright.
This is a very rare natural phenomenon, which is difficult to see with the naked eye, it may seem colorless, so it is also called "white».
On the planet there are a few places where the phenomenon of night rainbow repeated often enough. Among them, Yosemite National Park, Cumberland Falls in Kentucky and Victoria in Australia