There is a rainbow-color

If under the right conditions arise, the friend of all the rainbow may lose part of their tsvetov

Not every rainbow is multicolored. There is also an incredibly beautiful monochrome rainbow that appears under certain conditions. Sometimes a "cold" color just fall out of the rainbow, and there are strips of yellow, orange and red. Rainbow become monochrome, because it does not remain any other shades of color, which would create visible contrast. At sunset, the world sees a red dawn, because the gas in the atmosphere scatters blue light, like filtering it. During the day, this phenomenon is not too much, but when the sun sinks to the horizon, and between it and the observer there is the greatest distance, filled with atmosphere, a blue light is scattered. To a rainbow appeared, you need at least a little bit of water, and monochrome rainbow often occurs after heavy rains or during times of heavy fog. Water droplets scatter light in addition to a specific wavelength, thereby increasing the monochrome effect. The monochrome rainbow is not blue, green, and sometimes yellow. Usually this arc red. Sometimes people also see and white monochrome rainbow. When the fog particularly heavy, or when the clouds scatter light less accurate than the rain, so light can still form an arc in the sky. All colors of the spectrum there are mixed together, and the result is a white stripe. In fact, it looks like a cloud highlighted.

via factroom.ru