In the mornings, the skies are bluish in color because of the Rayleigh effect. This effect affects short wavelengths of light more than longer wavelengths. On the other hand, atmosphere is warmer during evenings, and there are also water molecules in the form of moisture. These molecules are larger than air molecules and are thus able to scatter longer wavelengths of air making the skies appear more orangish and reddish than at the time of sunrise. Also, during the course of the day, there is a lot of human activity, in addition to dust particles and pollutants rising up in the air.
All these particles make it possible for scattering of large wave lengths of light, making the skies more colorful and reddish during sunsets. According to atmospheric physicists David Lynch and William Livingston, the answer is "yes, and no. All "twilight phenomena" are symmetric on opposite sides of midnight, and occur in reverse order between sunset and sunrise, the authors note in "Color and Light in Nature" Cambridge University Press, That means there's no inherent, natural cause of a major optical difference between them.
However, two human factors break their symmetry. The first is in our heads. Some hues may be lost or perceived in a manner peculiar to sunset. At sunrise, however, the night's darkness has left us with very acute night vision and every faint, minor change in the sky's color is evident.
Human activities also drive a divergence between them. The dawn is clearer than any other time of day. Sunsets in the evening, and it always sets in the west direction. Sunset also lasts for almost 12 hours a day. The intensity of sun rays decreases as time passes. Sunsets never harm skin or body. Instead, they cool them off. Sunrise happens because the solar disk crosses the horizon and brings along some atmospheric effect too.
People just know the fact that the sun rises in the morning and sets in the evening but are unfamiliar with the mechanism that entitles this phenomenon every day. Sunrise only appears, for instance, when the upper limb of the sun excursus on the horizon.
Morning twilight occurs when the sky is brightening, but the sun is not up yet. When white rays pass through the surface, most of the shorter wavelength components are eliminated, i.
Blue and Green, while longer-wavelength rays are stronger; thus, they appear when the sun rises, i. Thus, the observer can see only these colors during sunrise.
Atmospheric refraction is so high in the evening that rays start to become distorted to the extent that the solar disk goes below the horizon. Evening twilight is different during the evening. Twilight occurs in three stages in the evening.
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