Ann & Steve Toon/naturepl.com
I have seen many double rainbows, but can you get triple or quadruple ones? If so, where are the best places to see them? What is the maximum number that could occur at the same time?
Len Winokur, Leeds, UK
We mostly only see rainbows when the sun is behind us. The reason is that light from the sun is internally reflected by the back of raindrops to re-emerge towards us. As it enters and leaves the drop, the white light is split into colours. Redder wavelengths emerge at wider angles than bluer ones, hence why red always appears as…
