Weather explained: How do rainbows form?

Weather explained
How do rainbows form?

Double rainbow beginning on land, in Torquay, Devon, and ending in the Atlantic Ocean.

This double rainbow was snapped leaping off of land into the Atlantic from Torquay, Devon.

Question: How does a rainbow form?

Answer:

As raindrops pass through rays of light, a rainbow's colours become visible despite being white light from the Sun.

Each colour has a different wavelength, as light hits raindrops the sunlight is refracted into the spectral colours. The light we see reaches our eyes at a 42-degree angle, forming a circle, and from our perspective the classic rainbow shape.

Video explainer:

Weather & Radar editorial team

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Weather explainedHow do rainbows form?

Weather explained
How do rainbows form?