Atmosphere

The atmosphere is a layer of gas that surrounds a celestial body. These gases are attracted thanks to the gravity of the bodies and in this way, they manage to stay in it if the force of gravity is sufficient and the temperature of the atmosphere is low. It is approximately 10,000 km thick and we find it surrounding the lithosphere and the hydrosphere at the same time. Formed of solid and liquid particles in a suspended statein addition to the gases included in it, which are attracted thanks to the earth’s gravity. Earth is not the only one that has an atmosphere, we can see it on other planets such as Mercury, Venus, Mars, Pluto, Uranus and even the sun.

Characteristics of the atmosphere

Among the main characteristics of the atmosphere we can mention the following:

• Its total mass is 5.1 x 1015 kg, however, that amount is variable depending on the amount of water vapor in it, time and place also influences the amount.
• Its density  is related to altitude , in this way, the higher the altitude, the lower the density.
• Factors such as temperature , humidity , the environment , are factors that directly influence the atmosphere.
• The atmosphere is divided into different layers, classified and named according to their variation in atmospheric temperature and pressure , creating a scale called the thermal-atmospheric gradient.

Composition of the atmosphere

It is made up mainly of gases , nitrogen and oxygen , ozone and carbon dioxide . At the same time, we can find a large amount of water vapor in it. The composition of the atmosphere varies, this because living beings also release and consume some types of gases that are in direct contact with the atmosphere.

Features

The atmosphere has important and vital functions for life. It allows the biochemical cycles to be adequate when it correctly supplies gases essential for life. It is responsible for preventing heat leaks and acts as a means of shielding against meteorites , due to the fact that the friction that these have when they come into contact with the air of the atmosphere disintegrate. It gives us important protection against solar radiation , without it we would be totally exposed to ultraviolet rays that are extremely harmful to living beings, to space objects that could collide with the earth and to important and dramatic variations in temperature and climate during the day and the night. The Oxigen What it provides is vital for our body, and necessary to be able to complete basic life functions.

Types of atmosphere

The atmosphere is divided into different layers, which vary according to temperature and pressure, thus forming a scale called the atmospheric thermal gradient. These layers would be the following:

• Troposphere : It is the lower layer, it is located in the first 6 to 20 kilometers high. Here the climatic and atmospheric phenomena occur .
• Stratosphere:  The layer ranges from 20 to 50 kilometers high and is arranged in various strata or phases of air. In it the transformation of oxygen into ozone occurs thanks to ultraviolet rays .
• Ozone:  The largest amount of ozone is produced in it and the ozone layer is located in it , which is responsible for giving protection to the planet from the direct impact of solar rays, absorbing more than 95% of them and protecting us against ultraviolet rays.
• Mesosphere:  This is the coldest layer. It can reach temperatures down to -80 ° C. It extends between 50 and 80 kilometers in height, and contains only 0.1% of the total mass of atmospheric air.
• Ionosphere:  It is also known as thermosphere . It ranges from 90 to 800 kilometers high, and in it the temperature increases depending on the degree of altitude, since the presence of the sun’s rays influences its temperature.
• Exosphere:  This is the outer layer . It starts around 800 kilometers and ends at 10,000 kilometers. In this atmospheric layer the atoms escape into space, and it is the transit zone between our planet and outer space.

Stages

The atmosphere has three different stages that are explained below:

• Prebiotic stage : The atmosphere underwent some important changes before having life, such as the condensation of water vapor that gave rise to the formation of the oceans and the dissolution of gases. The main gas it contains is nitrogen .
• Microbiological stage : In this stage, the formation of oxygen in the ocean began, which was used to oxidize substances in the ocean and the earth’s crust and then start the accumulation of said element in the atmosphere.
• Biological stage: Eukaryotic organisms with photosynthesis appeared. There was an increase in O2 until it reached its current concentration, which is 21%. The formation of the O3 layer originated, in charge of protecting us from ultraviolet rays.

Importance

The atmosphere is of utmost importance for life as it is protected by the Earth, absorbing a large part of the ultraviolet solar radiation from the ozone layer . In addition, it acts as a protective shield against meteorites and other space materials, which disintegrate into dust thanks to the friction they suffer when making contact with the air.

The atmosphere on other planets

There are several planets that have atmospheres, all with different characteristics:

• Venus : Its atmosphere is dense, it is made up mainly of CO2 and a small amount of carbon monoxide . Its temperatures are very high and it does not vary between day and night. Its winds are fast, approximately 360 km / hour.
• Mars : It is very tenuous, its pressure varies according to altitude, composed mainly of carbon dioxide and water vapor, among others. It is common to see winds and dust storms that last for months due to their density.
• Jupiter :  You can see clouds of different colors , which form at different heights and with different compositions.
• Saturn :  Saturn has dark bands and light areas, there are strong winds in the direction of the parallels .
• Uranus :  It has a thick atmosphere formed by a mixture of hydrogen, helium and methane, responsible for providing it with its characteristic color.
• Neptune :  It is made up of hydrogen , helium and a small percentage of methane gas , which gives it its greenish-blue color. Its particles are slightly further apart than they should be because of the temperature, which is –200 ° C.