Whether it's Saint Patrick's Day or National Find A Rainbow Day (April 3), everyone loves finding a rainbow - and maybe a pot of gold at the end. I can't tell you how to find a pot of gold, but I can ...

Double rainbows are two arcs of colour decorating the sky – literally two for the price of one. The main rainbow is usually brighter and of the usual pattern (red on top, violet at the bottom), and ...