Okay so there’s lots of particles in the atmosphere, the sun shines white light, the light gets scattered and depending on the angle, the sky gets its color. But like, how?
In: Physics
So light from the sun is all colors combined or white light as you said. When that light hits gas molecules in the atmosphere it causes electrons and protons in the gas molecules to oscillate. These oscillations causes electromagnetic radiation (that’s what light is) of the same frequency but in all directions instead of the straight line that the light was originally traveling in. This is the scattering effect that Rayleigh Scattering refers to.
Now why blue though? Blue light has a shorter wavelength with a higher frequency than the other light, like red. This means blue light (contained in the white light from the sun) causes the air molecules to oscillate more and thus scatter more. Due to some fancy math stuff blue light gets scattered nearly 10 times more than red light so the sky appears blue.
What about sunset and sunrise though? Well what happens here is basically the opposite. Since the light is hitting our perceived sky at an angle, the blue scattered light is deflected away from us making the sky more clear while red light, which isn’t getting scattered nearly at all, gets beamed right at us so sunsets and sunrises look red.
Latest Answers