The Sun is observed to be reddish when it is near the horizon, i.e., i

The Sun is observed to be reddish when it is near the horizon, i.e., in the morning and the evening. This is because

red light is least scattered by atmosphere

red light is most scattered by atmosphere

it is the colour of the Sun in the morning and evening

Earth's atmosphere emits red light

Answer is Right!

Answer is Wrong!

This question was previously asked in

UPSC NDA-1 – 2015

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The scattering of sunlight by particles in the atmosphere is described by Rayleigh scattering. According to Rayleigh scattering, the intensity of scattered light is inversely proportional to the fourth power of its wavelength (I ∝ 1/λ⁴). This means shorter wavelengths (like blue and violet) are scattered much more effectively than longer wavelengths (like red and orange). When the Sun is near the horizon, sunlight travels through a much greater thickness of the atmosphere. Most of the shorter-wavelength blue light is scattered away from the line of sight, leaving the longer-wavelength red and orange light to reach the observer, making the Sun appear reddish.

The reddish appearance of the Sun at sunrise and sunset is due to the atmospheric scattering of light, specifically the preferential scattering of shorter wavelengths.

The blue colour of the sky during the day is also a result of Rayleigh scattering, where the abundant blue light from the Sun is scattered in all directions across the sky.

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