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Why is the sky blue? Why are sunsets (and dusty stars) red?

SPU-21 Fall 2014

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This exercise will help you explore something about the colors of the Sun, by a simple analogy. The yellowish Sun of course has all colors, from violet to red, and beyond to both much shorter wavelengths (ultraviolet, x-rays, gamma rays, ...) and much longer wavelengths (infared, millimeter wave, radio, ...). The Earth's atmosphere, by preferentially absorbing and scattering certain colors of the Sun, creates the blue sky and the red sunsets.

What you'll need: