RAINBOWS –OH WHAT WOULD I DO TO SEE THE MAGIC, GLORY AND BEAUTY OF NATURE IN THIS ARCTIC WEATHER?
With so much snow blanketing the UK recently and leaving us with a grey sky, you must agree that to see one of the most beautiful wonders of nature must be the sight of a rainbow arching its way across our sky.
Artists have celebrated rainbows in their paintings and poets have been inspired to write about it – like this poem by William Wordsworth in 1807:
When heart leaps up when I behold
A rainbow in the sky;
So was it when my life began;
So is it now I am a man;
So be it when I shall grow old,
Or let me die.
Musicians have sung about it – like Mary Hopkins’ I Can Sing a Rainbow and Judy Garland Somewhere Over a Rainbow to name just two.
The rainbow arch has seven brightly coloured bands that always appear in a constant order; red, orange, yellow, green, blue, indigo and violet. One easy way to remember the colour sequence is with the saying Richard of York Goes Battling in Vain. The first letter of each word represents the first letter of each colour as it appears.
How the rainbow is formed?
The spectrum of colour in the sky is caused by the reflection and refraction (or bending) of sunlight as it falls at a certain angle on raindrops. The raindrops act as a prism, an angled transparent object that bends the sunlight, and the mixture of colours and the raindrops bend some colours more than others. These colours are separated out into the colours of the rainbow. The brightness of the colours depends on the size of the raindrops.
Sunlight has to pass through raindrops at the low angle for the colours to show as a semi-circular bow. That’s why you normally see rainbows after showers in the early morning or late evening, not at midday.
You can also see rainbows in clouds of spray when the sun shines on them, for example through a waterfall. To see a rainbow, the sun must be behind you. From an aircraft or a mountain top you can sometimes see a rainbow below as a complete circle.
Sometimes you may be lucky enough to see a double rainbow – a second arc is seen outside the main arc. The second rainbow is caused by light reflecting twice inside the water droplet.
Myths and Legends
The bible tells us that after Noah and the animals bobbed around on the water for 150 days, God set a mighty bow of brilliant colour in the sky. He told Noah: ‘This is the sign of the covenant I am making between me and you and every living creature with you, a covenant for all generations to come. I have set my rainbow in the clouds and it will be a sign of the covenant between me and the earth. Never again will the waters become a flood to destroy all life. Whenever the rainbow appears in the clouds, I will see it and remember the everlasting covenant between God and all living creatures of every kind on the earth.’
In classical mythology, it was Iris, the goddess of the elements who filled the clouds with water from the rivers and lakes to benefit agriculture, and Iris became the Patron Saint of farmers.
It’s a well known myth that whoever finds the end of a rainbow can claim the pot of gold that’s meant to be there inspired by the fact that a rainbow’s end is so elusive. In Ireland legend tells us that leprechauns and pots of gold are hidden at the end of the rainbow. One French legend insists that a magic pearl lies there, waiting to be recovered by whoever is lucky enough to find it. But these are just a few of the many myths and legends surrounding the rainbow that have appeared in nearly every culture of the world for many thousands of years.
Some primitive cultures are actually afraid of the rainbow, and some Eastern European cultures see the rainbow as a giant snake that drained the water from the rivers and lakes.
In medieval Germany, many believed that for forty years before the end of the world, no rainbows would appear. Thus, people were relieved to see a rainbow; as the saying goes: ‘So the rainbows appear, the world has no fear, until thereafter forty years.’
On the other hand, in the past, Slavonic people believed that looking at the base of a rainbow would bring death. Others believed that pointing at the highest point of a rainbow would bring bad luck (anything from being struck by lightning to developing an ulcer to losing a finger).
In Italy the rainbow is an arch of lighting, whilst the North American tribes greet it as the ‘bride of God’. For the Japanese it is the ‘floating bridge of heaven.’ In Classical mythology it was Iris, goddess of the elements, who filled the clouds with water from the rivers and lakes to benefit agriculture, and Iris became the Patron Saint of famers.
Many cultures all over the world believed that rainbows led to God. Some tribes of North American Indians called the rainbow a “Pathway of Souls.” In Japan, some refer to a rainbow as the “Floating Bridge of Heaven.” In Hawaii and Polynesia, legends call the rainbow the “path to the upper-world.” Legends of the people of the Austrian Alps say righteous souls go to heaven via the rainbow, whilst New Zealand legend say that dead chiefs went up a rainbow to the afterlife.
Certain primitive people actually feared the rainbow, and some eastern European cultures saw the rainbow as a giant snake that drained waters from the rivers and lakes and sometimes even sucked children up into the sky. African Zulu myths are full of stories of men and cattle being swallowed by rainbows never to be seen again.
The Science of the Rainbow
The science of the rainbow is just as fascinating as its mythology. It was in 1637 that a French philosopher and mathematician called Rene Descartes first used mathematical calculations to determine why a rainbow is seen at an angle of 42 degrees. His experiments led him to assume that the rainbow is caused when sunlight is reflected inside a droplet of water.
Then in 1666, Sir Isaac Newton came up with the first scientific explanation when he discovered that light is made up of different colours that the human eye does not see separately. No two people see exactly the same rainbow because the light enters the eyes is different for each person. This means that the rainbow has no end as the end is always changing as you change position. He made a hole in his window blind so that a beam of light passed through it and then put a prism in the beam light. This separated it into the seven coloured bands that make up the rainbow. Newton originally only named five primary colours- red, yellow, green blue and violet. Later he included orange and indigo giving us the seven colours. Legends informs us that Newton included the colour indigo because he felt that there should be seven colours rather than six, because, being a religious man he considered seven to be a biblical number.
Very few people know that the moon can create a rainbow as readily as the sun. On nights when the moon is shining through rain or there is a light mist, look out for a night rainbow. These night rainbows contain the same colours as daytime rainbows, but the eye doesn’t detect them at such low light intensity. However, the careful observer may glimpse these great bands of white, black and grey arching their way across the night skies.
But whatever the myths or scientific explanations, most of us today, like our ancestors, find a rainbow a thing of magic, glory and beauty.