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Question
Why does the Sun look reddish at sunset or sunrise ?
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Solution
At the time of sunset or sunrise, the Sun and its surroundings appear red because of the scattering of light. At the time of sunset or sunrise, the light rays from the Sun have to travel a long distance to reach our eyes through the Earth's atmosphere. In other words, we can say that when we look towards horizon, we are looking through more of Earth’s atmosphere than when we look overhead. The light reaching our eyes is rich in red colour as blue light is largely scattered away by the particles present in the Earth's atmosphere.
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