Actual and Apparent Position - Atmospheric Refraction

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Do you know the reason why there is an apparent shift in the position of the sun during sunrise and sunset. Well if no, this video will explain the reason behind it. Atmospheric refraction is responsible for apparent shift in position of the sun during sunrise and sunset. Our atmosphere is not a single layer but is composed of many layers of different densities. Atmospheric refraction is caused by the varying density of air among the different atmospheric layers. The optical density of our atmosphere decreases as we go higher. Light from the sun undergoes multiple refractions in different layers of air. This bending of light shifts the apparent position of the sun. An observer on earth would observe the sun rise two minutes before the actual time.