7 Colours of the Rainbow

rainbowHave you ever seen a rainbow? Sometimes when the sun is shining and it is rainy somewhere at the same time, you can see a rainbow. It's a huge arch of colours in the sky. It's caused by the light from the sun being broken up by water droplets in the atmosphere. The sun's light is "white", but the water droplets break it up into seven different colours, always in this order:

RED

ORANGE

YELLOW

GREEN

BLUE

INDIGO

VIOLET

There is an easy way to remember them (a mnemonic):
- Richard Of York Gave Battle In Vain

These colours are the "visible" part of the sun's radiation. But there are many other parts that are not visible to the human eye. For example:
- immediately below red is "infraRED"
- immediately beyond violet is "ultraVIOLET" (UV)

You can see more about colours here.

arch (noun): a curved symmetrical structure
atmosphere (noun): the air
colour (British English) color (American English)
droplet (noun): a very small drop of liquid
infra- (prefix): below
mnemonic (noun): a device or trick to aid the memory
ultra- (prefix): beyond

Contributor: Josef Essberger