Why is the sky blue simplified

However, the sky is not always blue. Sometimes, it appears yellow or red. The sky appears yellow whenever the air is clear and the sun is about to set because the sunlight has passed a long distance through the air and some of the blue light has been scattered away. Skies during sunsets appear red if the air has many small particles from natural sources or pollution caused by humans. Sunsets over the sea appear from red to orange because of the salt particles in the air.

Some opalescent materials, like the one shown here, have similar Rayleigh scattering properties to 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. From very high altitudes in the pre-sunrise or post-sunset skies, a spectrum of colors can be seen, 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.

With a large amount of atmosphere to pass through, light from the Sun or Moon reddens tremendously Farther away from the Sun, the sky turns gradually bluer. 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.

The total eclipse, as seen in Madras, Oregon in this picture, resulted in not only a spectacular 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.

Dust particles and water droplets are much larger than the wavelength of visible light. When light hits these large particles, it gets reflected, or bounced off, in different directions. The different colors of light are all reflected by the particle in the same way. The reflected light appears white because it still contains all of the same colors.

Gas molecules are smaller than the wavelength of visible light. If light bumps into them, it acts differently. When light hits a gas molecule, some of it may get absorbed. After awhile, the molecule radiates releases, or gives off the light in a different direction. The color that is radiated is the same color that was absorbed. The different colors of light are affected differently. All of the colors can be absorbed.

But the higher frequencies blues are absorbed more often than the lower frequencies reds. This process is called Rayleigh scattering. It is named after Lord John Rayleigh, an English physicist, who first described it in the 's. The blue color of the sky is due to Rayleigh scattering.

As light moves through the atmosphere, most of the longer wavelengths pass straight through. Little of the red, orange and yellow light is affected by the air. However, much of the shorter wavelength light is absorbed by the gas molecules. The absorbed blue light is then radiated in different directions.

For this reason, many cultures - including some Australian Aboriginal groups - associate lunar eclipses with blood. Rayleigh scattering works on other planets, too. Did you know that the sky on Mars is also blue?

When there are no big storms kicking red dust into the air, that is! This is a tricky question. But so do aeroplanes, and they fly more than 10, metres overhead. A majority of our atmosphere extends about 16 km upward, and this is where most of the Rayleigh scattering happens. Hello, curious kids! Ask an adult to send your question to us.