Friday, January 1, 2010

Rainbow beside me

Recently my nephew went cycling at Pasir Ris Park during his December school holiday. It rained suddenly and he was forced to take shelter temporary. He saw this rainbow just a few meters ahead of him. Using his phone camera he managed to capture it, but not as vividly as seen by him on the spot.



According to Wikipedia; "Rainbows can be observed whenever there are water drops in the air and sunlight shining from behind a person at a low altitude angle (on the ground)".

This must be the explanation as it was near evening when the phenomenon occurred.



Rainbow Visibility
Refraction and reflection in a raindrop, producing a rainbow.
White light separates into different colours (wavelengths) on entering the raindrop, as red light is refracted by a lesser angle than blue light. On leaving the raindrop, the red rays have turned through a smaller angle than the blue rays, producing a rainbow.


Source: english wikipedia, original upload 01. Jan 2003 by en:User:DrBob
http://en.wikipedia.org/wiki/Rainbow
http://en.wikipedia.org/wiki/File:Rainbow1.png



Religion and mythology
After Noah's Flood, the Bible relates that the rainbow gained meaning as the sign of God's promise that terrestrial life would never again be destroyed by flood (Genesis 9.13-17).


Picture: Noah's Thanks Offering (c.1803) by Joseph Anton Koch. Noah builds an altar to the Lord after being delivered from the Flood; God sends the rainbow as a sign of his covenant (Genesis 8-9).
http://en.wikipedia.org/wiki/Rainbow
http://upload.wikimedia.org/wikipedia/commons/f/f5/Joseph_Anton_Koch_006.jpg



Rainbow diagram showing the conventional arrangement of colours: Red Orange Yellow Green Blue and Violet. The colours shown do not necessarily correspond to actual wavelengths.



A vectorized version of Rainbow-diagram-ROYGBIV.PNG
Source:
http://en.wikipedia.org/wiki/Rainbow
http://upload.wikimedia.org/wikipedia/commons/thumb/c/c9/Rainbow-diagram-ROYGBIV.svg/800px-Rainbow-diagram-ROYGBIV.svg.png






Reference