• Question: why is the sky blue and not any other colour

    Asked by jayden1234 to Stuart, Alexander, Josh, Serena, Simone on 19 Jun 2013. This question was also asked by joanna22.
    • Photo: Stuart Archer

      Stuart Archer answered on 19 Jun 2013:


      When sunlight hits the molecules in the air, it can be ‘scattered’ by a process called ‘Rayleigh scattering’ – you can think of it as bouncing off the molecules, although it’s a bit more complicated than that (I’m not a physicist – I don’t fully understand it myself!). Sunlight is made up of lots of different colours of light (all the colours you see in a rainbow). When the light is scattered, the blue light is scattered more than the red light, so we see more of the blue light when it reaches the ground, making the sky blue.

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