Assuming the sun is below the skyline,  light has to travel through a lot of air. Blue light diffuses and travels back and forth, while red light is definitely less diffuse and shows up in your eyes.  
During dawn/dusk or moonrise/moonset, the light coming from the Sun (or Moon) must itself pass through a huge climatic dimension . The closer you are to the skyline, the more  light should permeate your surroundings. Blue light scatters in all directions, while red light scatters less effectively. This means that both the light from the sun circle (or the moon) itself and the light from the sun and moon regions will have a reddish tint. It melts only once before it gets into your eyes, making it especially red.

Additionally, in total sun-dominated darkness, when the moon's shadow crosses you, blocking direct sunlight from hitting the vast swath of  climate around you, the skyline turns red, but that's the difference. No. Light hitting the outside climate for the entire path is scattered here and there. That's why in many places the sky  still looks blue. Near the skyline, this light that scatters in all directions can scatter again before reaching the eye. Red light is the  frequency of light that is most likely to pass through, and in the long run surprises blue light, which is more effectively diffused. Assuming that the light of the filtered frequencies is better diffused, why doesn't the sky appear purple? Certainly, the violet light emitted by the environment is at a more noticeable level than the  blue light, but at the same time there are many different types of light mixed together. There are three types of cones (to distinguish between types) and monochromatic poles in  the eye, so he must brain-decode each of the four codes to classify the types. In addition to 
bars, each type of cone is sensitive to different frequencies of light, but each is somewhat activated by the sky. Our eyes are more responsive to blue, cyan, and green light frequencies  than  violet. Despite the fact that there are more purple lights, it's not enough just to hit the area of ​​strength of the signs our minds are telling us. 
This is a mixture of three things: 
 daylight consists of a wide range of frequencies of light, 
 environmental particles are small and scatter more limited frequency light much better than longer frequency light. Thing, 
In addition, our eyes 
have various reactions  that cause the sky to appear blue to people. If you can see well in the light, the sky will almost certainly appear more purple and brighter. Assuming there are only two types of cones (such as canines), we can see the blue sky during the day, but not the reds, oranges, and yellows at dusk. Anyway, don't be fooled. If you look at the earth from space, the earth is also blue, but the air is irrelevant.