secondary rainbow


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secondary rainbow

[′sek·ən‚der·ē ′rān‚bō]
(optics)
A faint rainbow of angular radius about 50° which may appear outside the primary rainbow of 42° radius, and which has its colors in reverse order to those of the primary. Also known as secondary bow.
References in periodicals archive ?
1987: Appearance of supernumeraries of the secondary rainbow in rain showers.
The reversed colors of the secondary rainbow arise because the emerging light rays cross the incoming light rays.
It is even dimmer than the secondary rainbow, and much harder to find because instead of forming away from the Sun, a tertiary rainbow forms around the Sun.
Because most of the light leaks out after just one reflection, secondary rainbows are usually much fainter than primary ones.