MARGARET AMALFITANO: Hello, my name is Margaret Amalfitano, and I'm living in Peachtree City, Georgia. And I'd like to ask a question for my children: Why is the sky blue?</s>ANN KELLAN, CNN SCIENCE CORRESPONDENT: Hey, that's a great question. Now, think of being in a bright sunny day with the sun shining overhead. The sun shines all different colors of the spectrum: yellow, red, orange, blue, violet. Now, the blue and the violet are shorter wavelengths than the red, yellow and orange, and those shorter wavelengths bounce off the molecules in the atmosphere and spread out all over the air. And that's why we see blue and violet, we see blue skies. Now, during a sunset, the sun sets further away from us in the atmosphere, and that gives those longer wavelengths a chance to scatter through the particulates and the molecules in the air. And that's why we see the beautiful reds and yellows of a sunset.
Ask CNN: Why Is the Sky Blue?