Question

what does clear sky blue

Answer 1

clear cloudless day-time sky is bluebecause molecules in the air scatterblue light from the sun more than they scatter red light. When we look towards the sun at sunset, we see red and orange colours because the blue light has been scattered out and away from the line of sight.

Answer 2

Due to atomspheric refraction .

The red light has a wavelength greater than blue light . So blue scatter more . Thus sunlight passes atmosphere,the finer particles in air scatter the blue light more strongly than red. So blue light enters in our eyes . Thusthe colour of the clear sky is blue