Solar system

Structure and composition of the Sun

Structure and composition of the Sun

From Earth we only see the outer layer of the Sun. It is called photosphere and has a temperature of about 6,000 ºC, with some colder areas (4,000 ºC) that we call sunspots.

The sun is a star. We can imagine it as a ball or onion that can be divided into concentric layers. From inside to outside they are:

Nucleus: It is the area of ​​the Sun where nuclear fusion occurs due to the high temperature, that is, the Sun's energy generator.

Radioactive Zone:: the particles that carry energy (photons) try to escape abroad on a trip that can last about 100,000 years because these photons are continuously absorbed and re-emitted in a different direction than they had.

Convective Zone: in this area the phenomenon of convection occurs, that is, columns of hot gas rise to the surface, cool and descend again.

Photosphere: It is a thin layer, about 300 km, which is the part of the Sun that we see, the surface. From here light and heat radiates into space. The temperature is about 5,000 ° C. In the photosphere there are dark spots and faculae that are bright regions around the spots, with a temperature higher than the normal photosphere and that are related to the magnetic fields of the Sun.

Chromosphere: It can only be seen in the totality of an eclipse of the Sun. It is reddish in color, very low density and very high temperature, half a million degrees. It is made up of rarefied gases and there are very strong magnetic fields.

Crown: large layer, high temperatures and very low density. It is made up of rarefied gases and gigantic magnetic fields that vary their form from hour to hour. This layer is impressive seen during the entire phase of a solar eclipse.

What is the sun made of?

The Sun is made with the same materials that are on Earth and on the other planets, since the entire Solar System formed at the same time in this area of ​​the Milky Way we occupy. However, these materials are not distributed in the same proportions, nor do they behave the same.

Chemical components Symbol %
HeliumI have7,8
NitrogenN 0,0084

Solar Energy: how does the sun work?

Solar energy is created inside the Sun, where the temperature reaches 15 million degrees, with a very high pressure, which causes nuclear reactions. Protons (hydrogen nuclei) are released, which fuse into groups of four to form alpha particles (helium nuclei).

Each alpha particle weighs less than the four protons together. The difference is ejected towards the surface of the Sun in the form of energy. A gram of solar matter releases as much energy as the combustion of 2.5 million liters of gasoline.

The energy generated in the center of the Sun takes a million years to reach the solar surface. Every second, 700 million tons of hydrogen are converted to helium ashes. In the process, 5 million tons of pure energy are released, so the sun is becoming lighter.

The sun also absorbs matter. It is so large and has such strength that it often attracts asteroids and comets that pass nearby. Naturally, when they fall into the Sun, they disintegrate and become part of the star.

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