Terry Pratchett. Education = "Telling lies to children". :) The term appeared in the book The Science of Discworld. http://en.wikipedia.org/wiki/Lie-to-children "the simplification of technical or difficult-to-understand material". http://wiki.lspace.org/mediawiki/index.php/Lies-To-Children
Why is the sky blue? (and also, why is the sun yellow?)
So, then. Why _isn’t_ the sky violet?
I think a more complete explaination is Rayleigh scattering of wavelengths with short (blue and violet) wavelengths being scattered more AND we have better perception of blue than violet with our eyes. See the natural daylight/sunlight spectrums below. Blue is slightly higher but our measurements and perceptions of light (and sound) is logarithmic so a small increase in intensity scale dominates more in our perception. I think. ☺
Pretty! I think I can see a little violet :)
“Our eyes don't work as well on violet as they do on blue.”
Hey kids. What colour would the sky be if there was no atmosphere?
Draw a diagram of the paths different colours of light takes from sun, into atmosphere and down to you.
What colour is the Sun?
Our sun is a yellow dwarf, because its visible radiation is most intense in the yellow-green portion of the spectrum and although its color is white, from the surface of the Earth it may appear yellow because of atmospheric scattering of blue light.
Now. :) Why do rainbows always appear ... over there. At a certain angle to the sun each time. ?
Of course we can't go away without looking at some spectral graphs for light from electric light bulbs.