And what's an atmospheric refraction?
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The atmosphere is curved like a giant convex lens.
As the air has a higher refractive index than a vacuum, light from below the horizon is bent slightly.
So we see the sun from slightly before it reaches the horizon.
Refraction is the term given to this bending,
and
Atmospheric states that it is caused by the atmosphere.
As the air has a higher refractive index than a vacuum, light from below the horizon is bent slightly.
So we see the sun from slightly before it reaches the horizon.
Refraction is the term given to this bending,
and
Atmospheric states that it is caused by the atmosphere.