It was around 1870 when the British physicist John William Strutt, better known as Lord Rayleigh, first found an explanation for why the sky is blue: Blue light from the Sun is scattered the most when ...

People across Europe were pretty confused last night, after a giant blue swirl appeared in the sky, lasting several minutes.

O n a clear, sunny day, the sky above us often glows a brilliant blue, a sight so commonplace that many of us rarely stop to ...

Of course, the sky is not always blue. And Rayleigh scattering also explains why the sky tends to be reddish when the sun is close to the horizon – at sunrise and sunset.

You might think that explaining why the sky is blue would be kind of simple. But even a brief explanation of it requires a lot of science. The colors of everything you see are produced in ...