The sky in Stuttgart, Germany has turned to sulfur. Why is this rare weather?

This phenomenon is caused by the refraction effect of the atmosphere. The earth's atmosphere is full of different gas molecules, and different atmospheric molecules have different scattering effects on light. In the earth's atmosphere, nitrogen molecules and oxygen molecules have the most content, while nitrogen molecules and oxygen molecules have stronger scattering ability for blue light. Therefore, the thicker the atmosphere, the more oblique the angle of the sun, and the closer the color of the sky will be to yellow and orange.

Different gas molecules in the atmosphere have different light scattering effects, so they will show different sky colors.

1, Rayleigh scattering? Let the sky appear in various colors:

The color of the sky is mainly determined by sunlight. Although the sun we see in various photos is yellow and orange, the sun is actually white and contains all colors of light. If you really want to give the sun a color, then the color that occupies the most spectrum in sunlight is actually green.

Although there are differences in the spectral colors of sunlight, the difference between each color is very small, so it will not have a decisive impact on the color of the sky. The atmospheric composition of the planet is the key to determine the color of the sky.

At noon, the sun is closest to the ground, and the influence of Rayleigh scattering is not obvious, while the human eye is most sensitive to blue, so at noon, the sky we see is generally blue or white; In the evening, the sun gradually reaches the other hemisphere, and the light needs a longer distance to reach the ground, and the effect of Rayleigh scattering will be more obvious. Blue light will gradually be scattered, and we will see a yellow, orange or even red sunset.

2, different planets have different colors of the sky:

The color of the sun will not change, but different planets have different atmospheres.

For example, on a planet with a thin atmosphere like Mars, the scattering of solar light has been very weak, so if we live on Mars, the sky is white and blue at noon or at night, and no other special colors will appear.

On Titan, because there is a lot of methane in the atmosphere, the scattering effect is very obvious. The sky is yellow and orange during the day. At night, the color of the sky will turn brown, thus forming a unique brown sunset. Other planets can even have green sunsets.

Why is the sky blue? This is a very difficult problem. With the introduction of Rayleigh scattering principle, this problem has been solved.

All the colors in the world are actually given by the sun, and even the color of the sky is closely related to the sun. The sun selflessly provides all the colors. What color the sky chooses depends on various molecules in the sky. Everything turns yellow in foggy days, which is actually a manifestation of Rayleigh scattering.