Sunlight is made up of all the different colors of light… and then some! The photosphere of our Sun is so hot, at nearly 6,000 K, that it emits a wide spectrum of light, from ultraviolet at the highest energies and into the visible, from violet all the way to red, and then deep into the infrared portion of the spectrum. The highest energy light is also the shortest-wavelength (and high-frequency) light, while the lower energy light has longer-wavelengths (and low-frequencies) than the high-energy counterparts. When you see a prism split up sunlight into its individual components, the reason the light splits at all is because of the fact that redder light has a longer wavelength than the bluer light.
Gjklnml


 fact that light of different wavelengths responds differently to interactions with matter proves extremely important and useful in our daily lives. The large holes in your microwave allow short-wavelength visible light in-and-out, but keep longer-wavelength microwave light in, reflecting it. The thin coatings on your sunglasses reflect ultraviolet, violet, and blue light, but allow the longer-wavelength greens, yellows, oranges, and reds to pass through. And the tiny, invisible particles that make up our atmosphere — molecules like nitrogen, oxygen, water, carbon dioxide, as well as argon atoms — all scatter light of all wavelengths, but scatter the shorter-wavelength light much more efficiently.

Because these molecules are all much smaller than the wavelength of light itself, the shorter the light’s wavelength is, the better it scatters. In fact, quantitatively, it obeys a law known as Rayleigh scattering, which teaches us that the violet light at the short-wavelength limit of human vision scatters more than nine times more frequently than the red light at the long-wavelength limit. (The scattering intensity is inversely proportional to the wavelength to the fourth power: I ∝ λ^-4.) While sunlight falls everywhere on the day side of Earth’s atmosphere, the redder wavelengths of light are only 11% as likely to scatter, and therefore make it to your eyes, as the violet light is.
When the Sun is high in the sky, this is why the entire sky is blue. It appears a brighter blue the farther away from the Sun you look, because there’s more atmosphere to see (and therefore more blue light) in those directions. In any direction you look, you can see the scattered light coming from the sunlight striking the entirety of the atmosphere between your eyes and where outer space begins. This has a few interesting consequences for the color of the sky, depending on where the Sun is and where you’re looking.

If the Sun is below the horizon, the light all has to travel through large amounts of atmosphere. The bluer light gets scattered away, in all directions, while the redder light is far less likely to get scattered, meaning it arrives at your eyes. If you’re ever up in an airplane after sunset or before sunrise, you can get a spectacular view of this effect.
It’s an even better view from space, from the descriptions and also the images that astronauts have returned.
During sunrise/sunset or moonrise/moonset, the light coming from the Sun (or Moon) itself has to pass through tremendous amounts of atmosphere; the closer to the horizon it is, the more atmosphere the light must pass through. While the blue light gets scattered in all directions, the red light scatters much less efficiently. This means that both the light from the Sun’s (or Moon’s) disk itself turns a reddish color, but also the light from the vicinity of the Sun and Moon — the light that hits the atmosphere and scatters just once before reaching our eyes — is preferentially reddened at that time.

And during a total solar eclipse, when the Moon’s shadow falls over you and prevents direct sunlight from hitting large sections of the atmosphere near you, the horizon turns red, but no place else. The light striking the atmosphere outside the path of totality gets scattered in all directions, which is why the sky is still visibly blue in most places. But near the horizon, that light that gets scattered in all directions is very likely to get scattered again before it reaches your eyes. The red light is the most likely wavelength of light to get through, eventually surpassing the more-efficiently-scattered blue light.
So with all that said, you probably have one more question: if the shorter-wavelength light is scattered more efficiently, why doesn’t the sky appear violet? Indeed, there actually is a greater amount of violet light coming from the atmosphere than blue light, but there’s also a mix of the other colors as well. Because your eyes have three types of cones (for detecting color) in them, along with the monochromatic rods, it’s the signals from all four that need to get interpreted by your brain when it comes to assigning a color.