Air is a mixture of gases, mainly nitrogen (78%) and oxygen O2 (21%). The bulk of the air (80%) is located in the lower layer of the atmosphere - the troposphere. The troposphere is located approximately 15 km above the Earth's surface. Above are the upper layers of the atmosphere, the air in which is so rarefied that they are unsuitable for life and are called "airless space".
The door to space
Above the troposphere, up to about 60 km in height above the Earth's surface, there is a huge airless space. This is the stratosphere. This layer is called "precosmos", or "door to space". Its main feature is the gradual increase in temperature along the vertical. From minus 60 оС at an altitude of 15-20 km from the Earth's surface to plus 2 оС, respectively, at the highest point of the stratosphere approximately at an altitude of 55-60 km.
The stratosphere is a stable layer of the atmosphere in which there is no air convection.
Water vapor in this layer is practically absent. But at an altitude of about 25 km, so-called "mother-of-pearl" clouds are sometimes observed. Their study and clarificationnature origin is being conducted by scientists all over the world.
The ozone layer is a protective barrier
An important discovery was the discovery in the stratosphere of the ozone layer, consisting of special oxygen molecules O3. This layer is only 2-3 mm thick, but it performs a very important function of protecting the planet and all life on it from the harmful effects of ultraviolet solar radiation. Studying the properties of the ozone shield, scientists found that freon gas, which was once actively used in industry, can destroy it. Currently, the use of freon is prohibited worldwide, since the destruction of the ozone layer will inevitably lead to the death of all life on Earth.
Beyond the earth's atmosphere begins an endless airless space. This is space. Scientists believe that the entire cosmos is made up of many galaxies. Each galaxy has its own structure. Humanity lives in a galaxy called the solar system, which consists of a star - the Sun - and the planets revolving around it.
Scientists distinguish such concepts as "near" and "far" space.
Near space objects are within the solar system. These are the planets and their satellites, the moon, meteorites, asteroids, comets. Deep space objects are located outside the solar system. These are stars, galaxies, nebulae, black holes. Their distances are measured in light years.
Airless space. Learning Difficulties
The main difficulty in studying the stratosphere is that at such a height the air is extremely rarefied. A person cannot survive here without a special spacesuit. In addition to the lack of oxygen for breathing, very low atmospheric pressure leads to the fact that the blood boils in the human body. Naturally, this is incompatible with life. Therefore, the study of the stratosphere began relatively recently - in the 30s of the 20th century, when the so-called stratostat was invented. For the first time, the Swiss O. Picard and P. Kipfer climbed to a height of 16 km on a stratospheric balloon. Three years later, in 1934, a Soviet crew climbed into the stratosphere. Unfortunately, this scientific expedition ended tragically - the entire crew died.
If the stratosphere is difficult to study, then space exploration is generally an incredibly complex, colossally expensive, and often impossible process at this stage in the development of science.
Spacecraft and interplanetary stations are used to study objects of the "near" space. Man has so far given way to machines in the direct study of space, since this place is extremely dangerous.
Studying "deep" space objects is only theoretically possible so far.
Anthropological use of vacuum
Vacuum is a space absolutely free from any kind of matter, including air, that is, it is also an airless space. In heavy and light industry, in medicine, constructionvacuum devices are widely used. In everyday life, this is a well-known vacuum cleaner. Getting absolute emptiness is incredibly difficult, and scientists are still on the way to this goal. A truly deep vacuum exists only in space.
The stratosphere is the perfect place for military pilots. Projectiles do not fly that high, and bombers or reconnaissance aircraft are practically invulnerable to air defense here. Unmanned balloons are launched to the "second floor" of the atmosphere, which help meteorologists predict the weather as accurately as possible.
The empty space called space is used to launch satellites that provide communication on the planet, help in the search for minerals, give forecasts of impending storms, cyclones and storms, and help prevent drought and floods.
The study of outer space has radically changed some of the ideas of scientists about matter.
In addition, the study of space is driven by endless human curiosity, the desire to "look through the window", to know the mysterious.