Color isn’t wavelength

Color is a visual phenomenon. Some would say that the essence of color is the qualia of seeing color (see Mary the color scientist). Qualia or no, it’s incorrect to make a direct association between color perception and the wavelength or frequency of light. They are related, of course. A source that produces monochromatic light…

Why do sunsets look like that?

During the day, the sky is blue and the sun appears a bright yellow. As the sun sets, it dims and reddens while the sky turns pink and orange. What causes that? You may have heard before that the sky’s blue color is due to something called Rayleigh scattering. As it turns out, the way…