From a physics standpoint, the blue sky is a lesson in wave dynamics and eye biology. While violet light actually bounces around even more than blue light, our eyes are not very good at seeing violet. We have special light detectors in our eyes called cones that are highly sensitive to blue, green, and red. Because the sky scatters mostly blue and violet, but our eyes are tuned to blue, we see the sky as a bright, clear blue instead of a pale purple.