Life above your head, or What is the Sun?

We are all accustomed daily to observe a bright heavenly body, giving us warmth and light. But does everyone know what the sun is? How is it arranged and what is it?

The sun is the closest star to the Earth, it takescentral place in the solar system. It is a huge hot gas ball (mostly hydrogen). The dimensions of this star are so large that it would easily accommodate a million planets like ours.

The sun played a decisive role in the development of life on theour planet and created the conditions for the formation of other bodies of its system. Observing the Sun at all times was an important occupation. People have always been aware of its life-giving power, they also used it to calculate time. Interest in solar energy and its capabilities is growing every day. Heating from the sun with the help of collectors is becoming more popular. Given the price of natural gas, such a free alternative seems even more tempting.

What is the Sun? Did it always exist?

It shines, as scientists have managed to find out, alreadymany millions of years and appeared along with the rest of the planets of the system from a huge cloud of dust and gas. The spherical cloud contracted and its rotation intensified, then it turned into a disk (under the influence of centrifugal forces). All the substance of the cloud has shifted to the center of this disk, forming a ball. So, probably, and the Sun was born. At first it was cold, but constant compression made it gradually hotter.

To imagine what the sun really is,very hard. At the center of this massive self-luminous body, the temperature reaches 15000000 degrees. The radiating surface is called the photosphere. It has a granular (granular) structure. Each such "grain" is a glowing substance as large as Germany. Often on the surface of the sun you can observe dark areas (sunspots).

Thermonuclear reactions to the Sun releasean unimaginable amount of energy that is radiated into space in the form of light and heat. To all other things, from here rushes and an incredible solar wind (a stream of particles).

Without the Sun, there would be no life on our planet. But along with heat and light, it also emits other forms of energy, such as X-rays and ultraviolet rays, which pose a threat to all living things. The ozone layer protects us, not missing most of the dangerous rays, but some of it passes, as evidenced by the tan on our skin.

The most powerful manifestation of solar activity isflash. In fact, it is an explosion caused by a plasma substance under the influence of a magnetic field. Although detailed flares have not yet been investigated, their occurrence is definitely of an electromagnetic nature.

Even preschoolers know what the sun is. But few people even think about the large-scale processes that occur on this fireball every second. The sun will not always be like this. Its fuel reserve is about 10 billion years. To find out how much more it will warm us and shine to us, it is necessary to clarify what part of life they have already lived. Lunar rocks and meteorites are no more than 5 billion years, which means that the age of the Sun is the same.

Previously it was believed that it would be just slowfade and cool down. Now they found out that this process will not be calm and quiet, a "dying" star is awaited with a real death agony. When the core is finally burned, the fire will eat the outer solar layers. The sun will turn into a massive red star, which will absorb Venus and Mercury and heat the Earth to incredible temperatures. The water will evaporate, life will cease to exist. Then a new energy source will appear in the outer layers of the Sun - helium. The shell will fall, the core will shrink to the state of a white dwarf.