On a bright, clear day, the sky stretches above us in a brilliant shade of blue. But have you ever wondered why? The answer lies in a fascinating phenomenon known as Rayleigh scattering, discovered by ...

When I was much younger, I would have said that blue was my favorite color. I had a blue 10-speed bicycle, and I loved to stare up into a brilliant blue sky. As I got older, though, I realized that I ...

When you take the sky and the ocean out of the equation, blue is surprisingly rare in nature. Less than one in ten plants have blue flowers, and it isn't common in animals, either. One reason is that ...