Escape the Spectre

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The splitting of light when it travels into a prism is called dispersion. The splitting is caused by refraction. Refraction occurs when light moves from one material to another. Each wavelength of light is refracted through a different angle, so the colours separate.


electromagnetic radiation - Why do prisms work (why is refraction frequency dependent)? - Physics Stack Exchange



One of the most famous effects of dispersion is the rainbow. These are always good to see, but there are many more atmospheric light effects to look out for.


A sun halo, sundogs and more | Today's Image | EarthSky


In this image, you can see a halo around the sun, two sundogs (parhelia) on the left and right of the halo, an upper tangent arc (on top of the halo), a parhelic arc (going through the two sundogs) and infralateral arcs (far left and right of the image). These are all caused by ice crystals refracting light.



Look here for some other light effects you may see in the atmosphere. I would really like to see the spooky Brocken Spectre. The light really is fantastic.


Take up my escape challenge by clicking on the image below.




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