secondary rainbow

atmospheric phenomenon

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Last updated

July 13, 2026

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A secondary rainbow is an atmospheric phenomenon that appears as a fainter, concentric arc outside the primary rainbow. Unlike the primary bow, which involves one internal reflection of light within a raindrop, the secondary rainbow is formed by light that undergoes two internal reflections. This double reflection causes the order of colors in the secondary rainbow to be reversed compared to the primary bow, with red on the inside and violet on the outside. Both types of rainbows are created by the refraction and reflection of sunlight by water droplets in the atmosphere.123

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rainbow
Occasionally, a secondary bow may be observed, which is considerably less intense than the primary bow and has its colour sequence reversed. The secondary rainbow has an angular radius of about 50° and hence is seen outside of the primary bow. This bow results from light that…
Read More
Occasionally, a secondary bow may be observed, which is considerably less intense than the primary bow and has its colour sequence reversed. The secondary rainbow has an angular radius of about 50° and hence is seen outside of the primary bow. This bow results from light that…
Read More