Actually...
You don't need anything too high tech to scatter light and create a moderately convincing sky blue. A box of smoke will do it (not very practical), or a colloidal gel (very practical), so long as the particles are small compared with the wavelength of visible light.
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notoolsovernight you're all luvvly an' 'orrible, Wed 18 Feb 2015, 15:02,
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But to specifically scatter blue light, and not the other colours, you need a pretty specific particle size, right? And if the molecules in air are the right size, any nanoparticle that also only scatters blue light would have to be the same size? Is there another type of scattering other than Rayleigh (Raliegh?) scattering?
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FridgeBadger, Wed 18 Feb 2015, 15:26,
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But..
You don't have to scatter blue light 'specifically'. Scattering is not like a dye or a pigment that has a particular characteristic wavelength or set of wavelengths. Rayleigh scattering affects all wavelengths, it just affects the shorter end of the spectrum (blue) more than the longer end (red). All you need is random particles smaller than about 450nm and nature will do the rest.
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notoolsovernight you're all luvvly an' 'orrible, Wed 18 Feb 2015, 15:39,
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