Video narration
Why does a clear daytime sky look blue, even when there's no ocean nearby? Sunlight seems white, but it carries a mix of colors. The colors are all there in sunlight. Between the Sun and your eyes is air, filled with tiny molecules. But the air isn't simply blue. Those molecules scatter blue light more strongly than red light, sending it away from the Sun and across the sky. So when you look up, blue light is reaching you from all directions-not just from the patch of sky near the Sun. Sunset checks the same idea. Sunlight travels through more air on its way to you, so more blue light scatters out of the direct path. Reds and oranges are left more prominent. That's why the daytime sky looks blue: air scatters blue sunlight toward your eyes from across the sky.