The quickest and easiest answer to why the sky is blue is that The air in the Earth's atmosphere absorbs the light that reaches it from the Sun.. Blue light scatters more than other colors because it travels in smaller, wider waves. And blue light spreads throughout the air, making our sky appear blue most of the time.
But if you want to know more in detail about Why is the sky blue, then we will tell you the scientific foundation a little more complete, in addition to other curiosities.
Composition of the Earth's atmosphere
First of all, let's start with a brief introduction to the composition of the Earth's atmosphere. As the composition of the atmosphere influences the color of which we see the sky.
The atmosphere is the outermost layer of our planet, which is the lightest, it is made up of various gases in different proportions. These gases are necessary for all life to exist on the planet. The atmosphere also contains suspended solids and liquids of natural origin or derived from human activities. The gases that make up the atmosphere are: nitrogen, oxygen, carbon dioxide, argon, noble gases, methane, hydrogen, nitrous oxide, carbon monoxide, ozone, water vapor and aerosols. Here we will tell you a little about the most important ones.
Nitrogen
Nitrogen makes up about 4/5 of the atmosphere; the remaining 1/5 is argon. The component of the atmosphere with the largest volume is nitrogen.
Nitrogen is an element essential for soil fertility; It is one of the most common gases in the atmosphere. However, plants only absorb 1% of this element because nitrogen is a gas that does not burn and is difficult to combine with other gases. As a result, certain bacteria are required to break down these nitrogen molecules for plants to use them.
Oxygen
It is the second most abundant element in the universe.. It represents 21% of the volume of the gas; however, it is also essential for all living organisms to breathe and grow. Its presence is necessary for all combustion processes to take place.
The Oxigen It is an essential chemical element for all living beings.. More than a quarter of all molecules in all living things are oxygen. This makes it easier for oxygen to combine with other elements to form new molecules.
Carbon dioxide
Carbon Dioxide (CO2) is one of many gases in the atmosphere. Its proportion in the atmosphere can vary according to time and place. CO2 is produced through the decomposition of organic matter, the respiration of living things, and the burning of fossil fuels.. Also, photosynthesis in plants and oceans can compensate for this.
Before the Industrial Revolution, there were 280 parts per million of carbon dioxide in the air. Nevertheless, levels of this greenhouse gas have increased dramatically over the years due to loss of plant life. On average, 410 parts per million of carbon dioxide are currently in the air. This is because atrophic reasons cause more than half of the 410 parts per million in the air.
Methane
Before the industrial age, our atmosphere contained approximately 200% of the methane it contains today. Estimates suggest that the current atmospheric concentration of methane is about 2 parts per million.
Compared to carbon dioxide, the greenhouse effect of methane is 25 times more powerful. Unfortunately, the effect of carbon dioxide in the atmosphere is only 17% of the total. This is because the effect of C02 is much greater when it is in smaller concentrations.
Ozone
Ozone forms a layer of protection against ultraviolet radiation from the sun. If it weren't for ozone, the Sun's radiation would destroy all life on the planet. The atmosphere of this gas changes seasonally and varies according to your altitude and latitude. It usually ranges between 15 and 35 kilometers in altitude.
aerosols
They are mainly involved in the formation of condensation nuclei, which are critical in the cloud formation. In addition, they cause air pollution due to their presence in the atmosphere. Some are also considered liquid or solid suspended particles. Aerosol sources include organic matter, dust particles, smoke, ash, and salt crystals. Certain natural processes can also create aerosols, for example the movement of waves in the sea.
Why is the sky blue?
The rainbow contains all the colors of sunlight. Sunlight appears white, but it is actually all the colors of the rainbow.
A prism is a crystal that has a unique shape, and when white light passes through it, it separates the light into all its colors.
La NASA on its page it has an explained section for children called: The Land of Magic Windows. Here it shows that there are many different types of light around us, beyond what we can see.
Some lights move in short waves and some lights move in long waves. Blue light travels in shorter waves and red light travels in longer waves. Light also travels in waves, like the energy that circulates in ocean waves.
Unless light travels through an object, it travels in a straight line. If it travels through an object, one of the following things can happen to the light:
- That reflect: like mirrors reflect things or a pond reflects the sky.
- That double: such as prisms and other objects that deflect light.
- That scattered: the same thing that happens with the gases found in the atmosphere.
Earth's atmosphere is full of gases and particles, which scatter light in all directions as it enters the atmosphere. Blue light reaching Earth is scattered more than other colors because it collides with smaller molecules in the atmosphere. and because its waves are shorter and smaller. Most of the time, we can see a blue sky due to the scattering of blue light in all directions.
When the sun is low on the horizon, the sky appears white or pale blue.. Light that has passed through many meters of air has been scattered and deflected by air molecules several times. The Earth's surface has also reflected and scattered light. When all of these colors are mixed together again, we see more white and less blue.
If the sky looks blue, why is the sunset red?
As the Sun sets low in the sky, it shines through more sections of the atmosphere, scattering much of the blue light. Red and yellow light pass without moving, and we can see it with our eyes.
What color is the sky on Mars?
Sunset on Mars
Mars has a thin atmosphere that contains carbon dioxide and is full of tiny dust particles. The atmosphere scatters light differently than Earth's atmosphere, made of gases and larger dust particles.
On this planet, the sky takes on an orange or red color during the day and a bluish-gray color when the Sun sets.. NASA has photos showing this on their Rovers and Landers.