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q |
Short wavelengths (blue and violet)
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of visible light are scattered more
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effectively than are longer
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wavelengths (red, orange). Therefore,
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when the Sun is overhead, an
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observer can look in any direction
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and see predominantly blue light that
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was selectively scattered by the gases
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in the atmosphere.
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q |
At sunset, the path of light must take
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through the atmosphere is much
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longer. Most of the blue light is
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scattered before it reaches an
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observer. Thus the Sun appears
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reddish in color.
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