Why the sky is blue and sunsets turn it red ??

 The sky does not have a colour of its own  !!!

When sunlight enters the atmosphere, tiny gas molecules scatter blue wavelength of light strongly than other colours.

This scattered blue light comes from all directions, our eyes perceive the sky as blue  !!!

Although violet light scatters  more strongly than blue light, our eyes are more sensitive to blue light.

That's why sky looks blue.

When the Sun is high on the sky ,  sunlight travels a shorter distance through the atmosphere before reaching our eyes.

These continue travelling through atmosphere and reach our eyes.

But when the Sun is near the horizon like early in the morning or later in the evening, sunlight must pass through a much thicker layer of air..

At this point, most of violet and blue light are scattered away from our eyesight.

What is remaining is longer wavelength of light i. e. reds, oranges and yelows  !!!

Result  :

Colours of the sky are not coming from Sun itself, but from Earth's atmosphere  !!!