If the weather ()

The sky we see is often blue, especially after a heavy rain. The sky is as blue as autumn water, which makes people feel relaxed and eager to fly. Why is the sky blue?

The atmosphere itself is colorless. The blue of the sky is atmospheric molecules,

, water drops, etc. And the sun * * * create the same picture.

When sunlight enters the atmosphere, long-wavelength colored light, such as red light, has great transmission power and can penetrate the atmosphere and shoot to the ground; Violet, blue and cyan light with short wavelength meets atmospheric molecules,

, water drops, etc. It is easy to happen.

. Scattered purple, blue and cyan light fills the sky, making it appear blue.

Why is the sky blue, not green or red?

First of all, you have to understand a truth: we

Things are colored because.

Catch them. Although sunlight looks white, all colors: red, orange, yellow, green, cyan, blue and purple exist in sunlight.

There are so many colors in the sky, why do I usually only see blue? You might ask.

If you think of light as a wave, you will solve the mystery. Light actually moves like a wave. Let's start.

A drop of rain fell on the ground.

Scenes in the movie. When this drop of rain falls on the water, it will be produced.

Waves, waves converge into a larger circle and spread in all directions. If these waves hit pebbles or other obstacles, they will bounce back and change the direction of the waves.

When the sun falls from the sky, it will continue to encounter some obstacles. Because the air that light must penetrate is not empty, it is made up of many tiny particles. Ninety-nine percent of them are either nitrogen or oxygen, and the rest are other gas particles and tiny floating particles, which come from automobile exhaust, factory smoke,

or

From the ashes of rocks. Although oxygen and nitrogen particles are just a drop of rain

A third, but they can still block the way of the sun. The light bounced back from these small stumbling blocks and naturally changed direction.

But so many colors of light have changed direction, why only see blue? You probably still don't understand.

We have to go back to what we just said.

inch

In the lake, if the small waves meet pebbles, the water surface will be chaotic; But if it is a "

",just like the kind you lift with your hands by the puddle."

",it is possible to simply overflow from the stone and reach the opposite puddle unimpeded. Well, it's like

and

Like waves, light waves of all colors have different "waves", that is, wavelengths: but unlike waves of water waves, their size can't be seen with the naked eye, because they are unimaginably small, only 1% of a hair! It must be very sensitive.

Can be accurately measured.

according to

The wavelengths of blue light and purple light are relatively short, which is equivalent to "

Wave "; The wavelengths of orange light and red light are relatively long, which is equivalent to "

"。 When encountering obstacles in the air, blue light and purple light are "scattered" everywhere because they can't cross those obstacles, covering the whole sky-the sky, so they are "scattered" into blue.

This "scattering" phenomenon was discovered.

call out

He found it 130 years ago, and so did he.

.

With the phenomenon of "dispersion", it can be explained as follows.

Of:

For example, the sky above you is blue, but in

Where heaven and earth meet, the sky looks almost white. Why? This is because the sun from

It takes longer to reach your destination-and what it brushes along the way-than it does to fall directly from the air.

Naturally, there are many. These huge numbers

Light is scattered many times in this way, so it looks white and transparent.

. I suggest you do a small experiment to verify it: take a glass of water, put it on a dark background, put a drop of milk and take another cup.

Light up one end of the cup and get close to it.

Light will appear in the water

Color. If you put more milk into water, the water will be whiter, because the light is repeatedly scattered by many milk particles, and the result is white. The truth followed.

The sky is white.

When the sun goes down in the evening, the sky turns red instead of blue, and the setting sun turns dark red. Due to the countless particles that the sunset glow encountered on the way to your place, the purple and blue parts of the sunlight scattered in all directions, leaving only a little orange-red light visible to the naked eye-because of their long wavelength and "big waves", they crossed the obstacles on the road.

However, if you look closely, you will find that,

A period of time after sunset will also appear dark blue. This used to be

Care about a strange thing, but not many.

50 years ago, the mystery was solved: the blue color that caused the dusk sky was a special substance. This special substance gathers into a thick layer at a height of 20 to 30 kilometers from the earth's surface, called

. This gas gives the falling sunlight a bright color.

The effect is that it blocks the sunlight.

Part of it lets the blue part pass almost unimpeded. Be the last one.

When it disappears, all the colors disappear in the night.

Ozone not only causes dusk.

Swallow a special light that you can't see:

Light, or

. You must have heard of it,

How dangerous it is to all living things (including you, of course). If it shines on your bare skin for too long, you will get

There is enough thickness everywhere to block as much ultraviolet rays as possible: this is extremely important for all life on our planet.

Unfortunately, today, this life-threatening protective layer has become thinner in many places, and even a big hole has been formed over the South Pole. And the killer of ozone destruction is "

"-a kind of hair gel that people use.

Or a substance used for refrigeration of refrigerators and air conditioners. This is a right.

Especially harmful substances, so many countries no longer use this "ozone killer".

Today we know why the sky in our eyes is blue. In fact, it is the same from the outside of the earth: the sea water covering two-thirds of our earth is also being distributed.

Although the land is brown and the forest is green, the sky is always blue-from the perspective of the universe, the whole earth is wrapped in a soft blue.

. from

Seen the earth outside.

This situation has been reported.

So the earth is called "

"Exactly. Its unique blue color is

. (copied from Baidu)