Our place in this world
Milky Way - Shash Galaxy
Solar Atmosphere - Photosphere

Photosphere - The atmosphere of the Sun begins with a 200-300 km of deeper visible edge of the sun's edge. These deepest layers of the atmosphere are called the photosphere. Since their thickness is no more than one three thousandths of the solar radius, the photosphere is sometimes conventionally called the surface of the Sun.
The density of gases in the photosphere is approximately the same as in the earth's stratosphere, and hundreds of times less than that of the earth's surface. The photosphere temperature decreases from 8000 K at a depth of 300 km to 4000 K in the topmost layers. The temperature of that middle layer, the radiation of which we perceive, about 6000 K. Under such conditions, almost all gas molecules disintegrate into separate atoms. Only in the most upper layers of the photosphere relatively slightly simple molecules and radicals of type H 2, OH, CH.

A special role in the solar atmosphere is played by a negative hydrogen ion that is a proton with two electrons. This unusual compound occurs in the thin external, the coldest layer of the photosphere with "sticking" to the neutral hydrogen atoms of negatively charged free electrons, which are supplied easily by ionized calcium, sodium, magnesium, iron and other metals. In the occurrence of negative hydrogen ions emit most of the visible light. The same light of the ions are eagerly absorb, because of which the opacity of the atmosphere with depth is growing rapidly. Therefore, the visible edge of the Sun and seems to us very sharp.
Almost all our knowledge of the Sun is based on the study of its spectrum - a narrow multi-colored strip having the same nature as the rainbow. For the first time, putting a prism on the sunshine path, Newton received such a strip and exclaimed: "Spectrum!" (Lat. Spectrum - "Vision"). Later, dark lines were noticed in the spectrum of the Sun and found them the borders of flowers.
In a telescope with a high increase, thin parts of the photosphere can be observed: the whole it seems to be covered with small bright grains - granules, separated by a network of narrow dark paths. Granulation is the result of mixing overlap warmer gas flows and lowered colder. The temperature difference between them in the outer layers is relatively small (200-300 K), but deeper, in the convective zone, it is greater, and stirring occurs significantly more intense. Convection in the outer layers of the Sun plays a huge role, determining the overall structure of the atmosphere. Ultimately, there is a convection as a result of complex interaction with sunny magnetic fields It is the cause of all diverse manifestations of solar activity. Magnetic fields participate in all processes in the sun. At times in a small area of \u200b\u200bthe solar atmosphere, concentrated magnetic fields occur, several thousand times stronger than on Earth. Ionized plasma is a good conductor, it cannot move across the magnetic induction lines of a strong magnetic field. Therefore, in such places, mixing and the rise of hot gases is slow down at the bottom, and the dark area occurs - the solar stain. Against the background of the dazzling photosphere, it seems completely black, although in reality the brightness is weaker only ten.
Over time, the magnitude and shape of the spots change greatly. Arriving in the form of a barely noticeable pore, the stain gradually increases its dimensions to several tens of thousands of kilometers. Large stains, as a rule, consist of a dark part (kernel) and less dark - seventeen, the structure of which attaches a stain type of the vortex. The stains are surrounded by brighter parts of the photosphere, called torches or torch fields.
The photosphere is gradually moving into a more rarefied external layers of the solar atmosphere - the chromosphere and the crown.
Solar atmosphere - chromosphere

Chromosphere (Greek. "Sphere of color") is named so for its reddish-purple color. It is visible during complete solar eclipses as a roded bright ring around the black disk of the moon, just overshadowed the sun. The chromosphere is very heterogeneous and consists mainly of oblong elongated tongues (spikula), which give it the appearance of burning grass. The temperature of these chromospheric jets is two to three times higher than in the photosphere, and the density of hundreds of thousands of times less. The total length of the chromosphere is 10-15 thousand kilometers.
The temperature growth in the chromosphere is explained by the propagation of waves and magnetic fields penetrating it from the convective zone. The substance is heated in about the same way as if it happened in a gigantic microwave oven. The speed of thermal movements of particles increases, collisions between them are rapidly, and atoms lose their external electrons: the substance becomes a hot ionized plasma. The same physical processes support and the unusually high temperature of the most outer layers of the solar atmosphere, which are located above the chromosphere.
Often during eclipses (and with special spectral devices - and without waiting for eclipses) above the surface of the Sun, you can observe the bizarre forms of "fountains", "clouds", "funnels", "bushes", "arches" and other brightly glowing formations from chromospheric Substances. They are in absentia or slowly changing, surrounded by smooth curved jets, which flow into the chromosphere or flow from it, rising to dozens and hundreds of thousands of kilometers. These are the most grandiose formations of the solar atmosphere - protuboyrans. When observed in a red spectral line emitted by hydrogen atoms, they seem on the background of a solar disk with dark, long and curved fibers.

Protubereans have about the same density and temperature as the chromosphere. But they are above it and are surrounded by higher, strongly sprinkled upper layers of the solar atmosphere. Protubereans do not fall into the chromosphere because their substance is maintained by magnetic fields of active areas of the Sun.
For the first time, the French Astronomer Pierre Zhansen and his English colleague Joseph Lyoulomer and his English colleague, Joseph Lomer, and his English colleague, Skotroscope in 1868, were observed. In 1868, the spectroscope gap is so that she crosses the edge of the Sun, and if a protubean is near him, then you can see the range of its radiation. Directing the gap different sites Printing or chromosphere, you can study them in parts. The spectrum of protuberans, as well as chromosphere, consists of bright lines, mainly hydrogen, helium and calcium. The radiation lines of other chemical elements are also present, but they are much weaker.
Some protuberans, having spent a long time without noticeable changes, suddenly seem to explode, and their substance at a speed of hundreds of kilometers per second is emitted into the interplanetary space. The type of chromosphere also changes, which indicates the continuous movement of the components of its gases.
Sometimes something similar to the explosions occurs in very small areas of the atmosphere of the sun. These are the so-called chromospheric flashes (the most powerful explosion-like processes, can last only a few minutes, but during this time the energy is distinguished, which sometimes reaches 10 25 J). They are usually several dozen minutes. During outbreaks in the spectral lines of hydrogen, helium, ionized calcium and some other elements, the luminescence of a separate section of the chromosphere suddenly increases ten times. Especially growing ultraviolet and X-ray radiation increases: sometimes its power is several times higher than the total power of the radiation of the Sun in this short-wave region of the spectrum to the outbreak.
Spots, torches, protuberances, chromospheric flashes - all this manifestation of solar activity. With an increase in activity, the number of these formations in the sun becomes more.
Solar atmosphere - crown

Crown - Unlike the photosphere and chromosphere, the external part of the sun atmosphere has a huge length: it extends more than millions of kilometers, which corresponds to several solar radii, and its weak continuation leaves even further.
The density of the substance in the solar crown decreases with a height of much slower than air density in the earth's atmosphere. Reducing the density of the air when the upward rise is determined by the attraction of the Earth. On the surface of the Sun, the power of gravity is much more, and it would seem that his atmosphere should not be high. In fact, it is unusually extensive. Consequently, there are some forces acting against the attraction of the sun. These forces are associated with huge speeds of atoms and electrons in the crown, heated to a temperature of 1-2 million degrees!
The crown is best observed during the full phase of the solar eclipse. True, for those for several minutes that it lasts, it is very difficult to draw not only individual details, but even a general view of the crown. The eye of the observer is barely just begins to get used to the suddenly coming twilight, and the bright ray of the sun appeared because of the edge of the moon, the bright ray of the Sun is already announced about the end of the eclipse. Therefore, often sketches of the crown made by experienced observers during the same eclipse, varying. It was not possible to even accurately determine its color.
The invention of photography gave astronomers an objective and documentary research method. However, get a good shot of the crown is also not easy. The fact is that its closest to the Sun part, the so-called inner crown, is relatively bright, while the far exterior crown appears to be very pale radiance. Therefore, if the external crown is clearly visible in the photos, the inner turns out to be disturbed, and in the pictures where the parts of the inner crown are viewed, the external is completely imperceptible. To overcome this difficulty, during eclipses, you usually try to get a few snapshots of the crown at once - with large and small excerpts. Or the crown is photographed by placing a special "radial" filter before photoplastic, weakening the ring zones of bright inner parts of the crown. In such pictures, its structure can be traced to a lot of solar radius.
Already the first successful photos allowed to be discovered in the crown a large number of Details: Coronal rays, all sorts of "arcs", "helmets" and other complex formations, clearly related to active regions.
The main feature The crown is a radiant structure. Coronal rays have the most diverse form: sometimes they are short, sometimes long, there are rays straight, and sometimes they are very curved. Back in 1897, Pulkovsky Astronomer Alexei Pavlovich Ghansky discovered that the general type of solar crown changes periodically. It turned out that this is due to the 11-year-old solar activity cycle.
With the 11-year period, both the overall brightness and the shape of the solar crown is changed. In the era of the maximum of solar spots, it has a relatively rounded form. Light and directed along the radius of the sun rays of the crown are observed both in the solar equator and in the polar regions. When there are few stains, the coronal rays are formed only in equatorial and medium latitudes. The shape of the crown becomes elongated. Poles appear characteristic short rays, so-called polar brushes. In this case, the overall brightness of the crown decreases. This interesting feature The crowns, which is arguable, is associated with the gradual movement during the 11-year cycle of the area of \u200b\u200bpredominant stains. After a minimum, the stains begin to occur on both sides of the equator on the latitudes of 30-40 °. Then the staining zone is gradually lowered to the equator.
Careful studies have made it necessary to establish that there is a certain connection between the crown structure and individual formations in the atmosphere of the Sun. For example, bright and straight coronal rays are usually observed over stains and torches. In their direction, neighboring rays bent. Based on the coronal rays, the brightness of the chromosphere increases. This area is called usually excited. It is hot and tightly neighboring, unexcited areas. Above stains in the crown there are bright complex formations. Protubereans are also often surrounded by the shells of coronal matter.
The crown turned out to be a unique natural laboratory in which the substance can be observed in the most unusual and unattainable conditions on earth.
At the turn of the XIX-XX centuries, when plasma physics actually did not exist, the observed features of the crown were inexplicable mystery. So, the color of the crown is surprisingly similar to the sun, as if his light reflects the mirror. At the same time, however, in the inner crown, they completely disappear for the solar spectrum of the lines of the line. They again appear far from the edge of the sun, in the outer crown, but already very weak. In addition, the crown light is polarized: the planes in which the light waves oscillate are located mainly regarding the solar disc. With the removal from the Sun, the proportion of polarized rays first increases (almost up to 50%), and then decreases. Finally, in the spectrum of the crown appear bright emission lines, which are almost until the middle of the XX century. Failed to identify any of the known chemical elements.
It turned out that the main reason for all these features of the crown is a high temperature of a strongly sprinkled gas. At a temperature of more than 1 million degrees, the average rate of hydrogen atoms exceed 100 km / s, and the free electrons are in 40 times more. At such speeds, despite the strong affability of the substance (only 100 million particles in the cc, cm, which is 100 billion times raising air on Earth!), Comparatively frequent collisions of atoms, especially with electrons. The forces of electronic shocks are so great that the atoms of light elements are almost completely deprived of all their electrons and only "naked" nuclear nuclei remain from them. Heavier elements retain the deepest electronic shells, moving to a high degree of ionization state.
So, coronal gas is a highly elevated plasma; It consists of many positively charged ions of all sorts of chemical elements and a little more free electrons arising from the ionization of hydrogen atoms (one electron), helium (two electrons) and heavier atoms. Since mobile electrons play the main role in such gas, it is often referred to as electron gas, although it means that the presence of such a number of positive ions is implied, which would fully ensure the plasma neutrality as a whole.
White color The crown is explained by the dissimilar sunlight on free electrons. They do not invest their energy during dissipation: fluctuating the light wave tact, they only change the direction of the scattered light, while polarizing it. The mysterious bright lines in the spectrum are generated by the rapid radiation of highly angular iron, argon, nickel, calcium, calcium and other elements that occur only in conditions of severe permafrost. Finally, the absorption lines in the outer crown are caused by dissipation on dust particles, which are constantly present in the interstellar medium. And the absence of a line in the inner crown is due to the fact that when scattered on very fast moving electrons, all light quanta test such significant changes in frequencies that even the strong phraunga powers of the solar spectrum line are completely "closed".
So, the crown of the Sun is the most external part of its atmosphere, the most sparse and the hottest. We add that she and the closest to us: it turns out, it extends away from the sun in the form of a constantly moving plasma flow - solar wind from him. Near the Earth, its speed is an average of 400-500 km / s, and sometimes reaches almost 1000 km / s. Spreading far beyond the limits of the orbits of Jupiter and Saturn, the solar wind forms a giant heliosphere, a border with an even more rarefied interstellar medium.
In fact, we live surrounded by the solar crown, although protected from its penetrating radiation a reliable barrier in the form of an earth's magnetic field. Through the crown, solar activity affects many processes occurring on Earth (geophysical phenomena).
How the sun affects the ground

The sun illuminates and warms our planet, without this, life on it is not only a person, but even microorganisms would be impossible. The Sun is the main (although not the only one) engine taking place on earth processes. But not only heat and light gets the earth from the sun. Different kinds Solar radiation and particle streams have a constant effect on her life.
The sun sends electromagnetic waves to the ground of all spectrum areas - from multi-kilometer radio waves to gamma rays. Earth's surroundings also achieve charged particles of different energies - both high and low and medium. Finally, the sun emits a powerful flow of elementary particles - neutrino. However, the impact of the latter on earth processes is dismissively small: for these particles, the globe is transparent, and they fly freely through it. Only a very small part of the charged particles from the interplanetary space falls into the atmosphere of the Earth (the rest rejects or delays the geomagnetic field). But their energy is enough to cause the polar radiances and perturbations of the magnetic field of our planet.
Electromagnetic perturbation is subjected to strict selection in the earth's atmosphere. It is transparent only for visible light and the nearest ultraviolet and infrared radiation, as well as for radio waves in a relatively narrow range (from centimeter to meter). All other radiation is either reflected, or is absorbed by the atmosphere, heating and ionizuya its upper layers.
The absorption of X-ray and hard ultraviolet rays begins on the outputs of 300-350 km; At the same heights, the longest radio waves coming from space are reflected. With strong splashes of solar x-rays from chromospheric flashes, X-ray quanta penetrates up to the heights of 80-100 km from the surface of the Earth, ionizuet the atmosphere and cause a violation of short waves.

Dark, ominous type of region in the left side of the solar disk are so-called coronal holes. These areas are located above the surface, where the power lines of the solar magnetic field go to the interplanetary space, are characterized by reduced pressure. Coronal holes began to intensively study from satellites since the 1960s in ultraviolet and X-ray light. It is known that they are sources of intensive solar wind, which consists of atoms and electrons flying away from the Sun along the open-powered magnetic field lines.

Our Sun.

Soft (long-wave) ultraviolet radiation can penetrate even deeper, it is absorbed at an altitude of 30-35 km. Here ultraviolet quanta are divided into atoms of oxygen molecules with subsequent ozone formation. Thus, it is not created transparent for ultraviolet "ozone screen", protecting life on Earth from the faded rays. Not absorbed part of the most long-wave ultraviolet radiation comes to the earth's surface. It is these rays that cause tan in people.
The radiation in the visible range absorbs weakly. However, it is dissipated by the atmosphere even in the absence of clouds, and part of it returns to the interplanetary space. Clouds consisting of water droplets and solid particles significantly enhance the reflection of solar radiation. As a result, it comes to the surface of the planet, about half of the falling light falling on the boundary of the earthly atmosphere.
The amount of solar energy coming to the surface of 1 sq. Meter, deployed perpendicular to the solar rays on the boundary of the earth's atmosphere, is called solar constant. It is very difficult to measure it from the ground, and therefore the values \u200b\u200bfound before the start of space studies were very approximate. Small fluctuations (if they really existed) knowingly "tone" in the inaccuracy of measurements. Only the implementation of a special space program to determine the solar constant made it possible to find its reliable value. According to the latest data, it is 1370 W / m 2 with an accuracy of 0.5%. Vibrations exceeding 0.2%, during the measurement time was not detected.
On Earth, radiation is absorbed by the land and ocean. The heated earth surface in turn radiates in the long-wavelength infrared area. For such radiation nitrogen and oxygen, the atmosphere is transparent. But it is greedyly absorbed by water vapor and carbon dioxide. Thanks to this small component, the air shell holds heat. This is the greenhouse effect of the atmosphere. There is an equilibrium between the advent of solar energy to the ground and its losses on the planet: how much does it come, so much and is consumed. Otherwise, the temperature of the earth's surface along with the atmosphere either constantly increased, or fell.

- All phenomena of solar activity are associated with the exit to the surface of the sun magnetic fields. Already the first measurements of the Effect of Zeeman, conducted at the beginning of the 20th century, showed that the fields in stains are characterized by the tension of the order of several thousand earsted, and such fields are implemented in areas with a diameter of 20,000 km. Modern instruments for measuring the fields in the Sun allow not only to measure the value of the field with an accuracy of 1 e, but also judge about the angle of tilt the tension of the magnetic field. It is found out, for example, that torches are areas with fields 5-300 E. In the shade of the fields of the fields reach 1000-4500 E. In the center of the spot, the field is directed upwards, along the radius of the sun, but the periphery increases its slope, and in half the field almost parallel to the solar surface. The field is concentrated in separate harnesses.

The sun is very restless. In this picture, presented in the conventional colors, is depicted an active area located on the edge of the Sun disk. Hot plasma breaks out of the solar photosphere and moves along the magnetic field lines. Very hot regions are marked red, indicating that in some loops of the magnetic field more hotstoth is distributed than other loops. The loop of the magnetic field is very high, so the earth can easily fit inside them.

Our Sun.

The middle surface of the solar surface has an order of 1 e, it consists, apparently, from individual cells with 10 e on their borders. Such a field is observed near the poles of the Sun, whereas on low latitudes it is often perturbed by strong fields of active areas. These strong local fields are indignant not only to the photosphere, but penetrate into the outer layers. In the chromosphere over the shadow of the spots, their value can reach 1000 e, above the half and the torches of 100 E. The indirect evidence says that the fields in the crown over the active region of 10-0.1 E. T., the active area (or the activity center) is identified With the place of high voltage magnetic field. The lower base of the active region is torches and stains - located in the photoosphere. The upper part is manifested as a chromospheric torch (floccul), and in the crown - like coronal condensation.
Most often, active areas are characterized by two poles of the opposite polarity - so-called. Bipolar centers, although there are both multipolar and unipolar areas. The opposite polarity poles are connected by the arches system with a length of up to 30,000 km and up to 5000 km high. The peaks of the archer are slowly raised, and about the poles gas flows down, towards the photosphere.
The development of the active area in time is peculiar. With the amplification of the magnet field in the photoosphere, a torch occurs, gradually increasing its area and brightness. After about a day, several dark points arise in it, which then develops in solar spots. The tenths - the eleventh days of the life of the region are characterized by the most stormy processes in the chromosphere and crown. At the same time, the size of large groups of stains reaches 20 helicual degrees in longitude and 10 by latitude or 2400 km x 12,000 km. After 1-3 months, the spots gradually disappear, the giant protubenets hangs over the region. After six months or a year, this area disappears.
For a medium spot with a field of 3000 e magnetic energy, at least 10 times greater than kinetic. Energy of convective movements. But in the convective cell necessarily there is a horizontal movement, perpendicular to the field direction. The field prevents horizontal movement, as a result of which convection in stains is significantly weakened. The difficulty of convection leads to a smaller flow of energy into the area of \u200b\u200bthe spots, since the energy in the deep layers is transferred by convective movements. Probably, the lower temperature and "black" spots are connected with this.
The granules observed in the shadows (with dimensions up to 300 km and the average life of 15-30 min) indicate the presence of a strongly modified convection. It consists here in the fact that separate elements Hot gas breaks through spots along the field to photospheric heights. There they are expanding, squeezing the ambient gas with the field. Dense gas is lowered, the movement of gas resemble the movement up and down in closely arranged pipes with a slightly changing cross section (i.e. with a minor deformation of the power lines). In many other cases, when moving gas in protuberances, in the coronal arches of the trajectory of the gas movement also coincide with the progress of power lines.
The degree of field effect on the structure of an external atmosphere depends on the size of the magnetic flux overlooking the surface (1017-1022 μs) and on how much it changes with height and in time.

The photosphere is the layer of the solar atmosphere, which we see into the telescope and perceive the eye as a surface, has a temperature of about 5,800 s. During the minimum of solar activity, the surface of the photosphere relative to the spacing. All the vortices of thermal reactions, giving a star to its energy, will be deep inside. But with the beginning of a new cycle, the energy of all these internal processes begins to break out. An increase in solar activity is a symptom of magnetic shifts under the surface of the Sun. During this period, the magnetic field of the star loses its polarity. On its surface, stains begin to appear - relatively cold areas, the temperature of which does not exceed 4,500 ° C. Against the background of a hotter photocheres, they look like dark. The magnetic field of spots is significantly higher than the surrounding space. In the area through which the so-called "twisted" filaments of the spot field pass, sometimes there are situations, with more possibly "re-browing" of magnetic fields. Here, solar flares are actively developing - the strongest manifestation of solar activity, influencing the ground. It affects all Threat to the solar atmosphere. Their development is accompanied by complex movements of ionized gas, its luminescence, acceleration of particles. The high solar outbreak energy reaches a huge value comparable to the amount of solar energy obtained by our planet for a whole year. This is approximately 100 times the most of the entire thermal energy, which could be obtained by burning all the explored oil, gas and coal reserves. Strong outbreaks are a very rare phenomenon, with a coaster, the energy is released in the upper chromosphere or lower crown, generating short-term electromagnetic radiation in a wide range of wavelengths - from rigid X-ray radiation to radio waves. Its main part is released in the form of kinetic energy of particles moving in the crown and interplanetary space with speeds up to 1000 km / s, and the energy of rigid electromagnetic radiation. The substance is thrown away from the surface of the Sun at a speed of 20 to 2,000 km / s. His mass is estimated at billions of tons. And its energy, spreading in space, in less than 4 minutes reaches Earth. The flow of corpuscular particles emitted by the Sun, with a speed of about 500 km / s cut into the magnetic field of the Earth, causing indignation in it and affecting the processes on our planet.

The sundespite the fact that it is listed "Yellow Dwarf" So great that we even hard to imagine. When we say that the mass of Jupiter is 318 masses of the Earth, it seems incredible. But when we learn that 99.8% of the mass of the entire substance falls on the sun - it just goes beyond understanding.

Over the past years, we have learned a lot about how "our" star is arranged. Although humanity has not invented (and is unlikely to ever invent) a research probe capable of physically approach the Sun and take samples of his substance, we are not bad about its composition.

Knowledge of physics and opportunities give us the opportunity to say exactly what the sun consists of: 70% of its mass is hydrogen, 27% - helium, other elements (carbon, oxygen, nitrogen, iron, magnesium and others) - 2.5%.

However, only this dry statistics are our knowledge, fortunately, are not limited.

What is inside the sun

According to modern calculations, the temperature in the depths of the Sun reaches 15 to 20 million degrees Celsius, the density of the stars reaches 1.5 grams per cubic centimeter.

The source of energy of the Sun is a constantly running nuclear reaction that flows deep beneath the surface, due to which the high temperature of the shone is maintained. Deep under the surface of the Sun, hydrogen turns into helium as a result of a nuclear reaction with concomitant energy release.
"The zone of nuclear synthesis" of the sun is called sunny kernel And has a radius of approximately 150-175 thousand km (up to 25% of the radius of the Sun). The density of the substance in the solar core is 150 times the density of water and almost 7 times is the density of the density substance on Earth: Osmia.

Scientists know two types of thermonuclear reactions of the stars under stars: hydrogen cycle and carbon cycle. In the sun mainly flows hydrogen cyclewhich can be divided into three stages:

• hydrogen cores turn into a deuterium kernel (hydrogen isotope)
• hydrogen kernels turn into an unstable helia isotope kernel
• the products of the first and second reaction are binding to the formation of a stable helium isotope (helium-4).

Each second, 4.26 million tons of stars substance turn into radiation, however, compared with the weight of the Sun, even this incredible value is so little that they can be neglected.

The heat yield from the bowels of the Sun is performed by absorbing electromagnetic radiation coming from below and its further re-ease.

Closer to the surface of the Sun emitted from the bowels energy is transferred mainly in convection zoneSun using the process convection - stirring of the substance (warm flows of the substance rise closer to the surface, the cold are lowered).
The convection zone lies at a depth of about 10% of the solar diameter and comes to almost the surface of the star.

Atmosphere of the Sun.

Above the convection zones begins the atmosphere of the sun, in it the transfer of energy occurs again by radiation.

Photosphere They call the lower layer of the solar atmosphere - the visible surface of the sun. Its thickness corresponds to the optical thickness of approximately 2/3 units, and in absolute values \u200b\u200bof the photosphere reaches a thickness of 100-400 km. It is a photosphere that is the source of the visible radiation of the Sun, the temperature is from 6600 K (at the beginning) to 4400 K (at the top edge of the photosphere).

In fact, the sun looks like a perfect circle with clear boundaries only because on the border of the photosphere, its brightness falls 100 times in less than one second of the arc. Due to this land, the sun disc is noticeably less bright than the center, their brightness is only 20% of the brightness of the disk center.

Chromosphere - The second atmospheric layer of the sun, the outer shell of the star, a thickness of about 2,000 km surrounding the photosphere. The temperature of the chromosphere increases with a height of 4,000 to 20,000 K. Watching the sun from the ground, we do not see the chromosphere due to low density. It can only be observed during solar eclipses - an intense red glow around the edges of the solar disk, this is a chromosphere of a star.

Solar crown - The last outer shell of the solar atmosphere. The crown consists of protuberances and energy eruptions, outgoing and erupting a few hundred thousand and even more than a million kilometers into space, forming sunny wind. The average coronal temperature is up to 2 million k, but it can come up to 20 million K. However, as in the case of chromosphere - from Earth, the solar crown is visible only during eclipses. Too small density of the substance of the solar crown does not allow it to observe it under normal conditions.

sunny wind

sunny wind - the flow of charged particles (protons and electrons) emitted by the heated by the external layers of the star atmosphere, which extends to the borders of our planetary system. The lines every second loses millions of tons of their mass, due to this phenomenon.

Near the Orbit of the Planet Earth The speed of solar particles reaches 400 kilometers per second (they move along our star system with supersonic speed), and the density of solar winds from several to several tens of ionized particles in a cubic centimeter.

It was the solar wind that the atmosphere of the planets, "blowing out" the gases contained in it in it open space, he is largely responsible for. To resist the solar wind of the earth allows the magnetic field of the planet, which serves as invisible protection from the solar wind and prevents the outflow of atmospheric atoms into open space. In the collision of the solar wind with the magnetic field of the planet, the optical phenomenon occurs, which on the ground we call - polar Lightsaccompanied by magnetic storms.

However, the unemployment and the benefits of the solar wind - it is he "blows out" from the solar system and the space radiation of galactic origin - and therefore protects our star system from external, galactic radiation.

Looking for the beauty of polar radiances, it is difficult to believe that these rims are visible sign of the solar wind and the magnetosphere of the Earth

Stars are entirely made of gas. But their external layers are also called the atmosphere.

The atmosphere of the Sun begins 200-300 km. Deeper visible edge of the solar disk. These deepest layers of the atmosphere are called the photosphere. Since their thickness is no more than one three-thousandxal fraction of the solar radius, the photosphere is sometimes conventionally called the surface of the sun. The gas density in the photoosphere is approximately the same as in the earth's stratosphere, and hundreds of times less than that of the earth's surface. The photosphere temperature is reduced by 8000 K at a depth of 300 km. up to 4000 K in the uppermost layers. In a telescope with a high increase, thin parts of the photosphere can be observed: the whole it seems to be covered with small bright grain - granules separated by a network of narrow dark paths. Granulation is the result of mixing the pop-ups of more warm gas flows and descending colder. The temperature difference between them in the outer layers is relatively small, but deeper, in the convective zone, it is greater, and stirring occurs significantly more intense. Convection in the outer layers of the Sun plays a huge role, determining the overall structure of the atmosphere. Ultimately, it is convection as a result of complex interaction with solar magnetic fields is the cause of all diverse manifestations of solar activity. The photosphere is gradually moving into a more rarefied external layers of the solar atmosphere - the chromosphere and the crown.

Chromosphere (Greek. "The Sphere of Light") is named so for its reddish-purple color. It is visible on time full of solar eclipses like a roded bright ring around the black disk of the moon, just overshadowed the sun. The chromosphere is very heterogeneous and consists mainly of oblong elongated tongues (spikula), which give it the appearance of burning grass. The temperature of these chromospheric jets is 2-3 times higher than in the photosphere, and the density is hundreds of thousands of times less. The total length of the chromosphere is 10-15 thousand km. The temperature growth in the chromosphere is explained by the propagation of waves and magnetic fields penetrating it from the convective zone. The substance is heated in about the same way as if it happened in a gigantic microwave oven. The speed of thermal movements of particles increases, collisions between them are rapidly, and atoms lose their external electrons: the substance becomes a hot ionized plasma. The same physical processes support and the unusually high temperature of the most external layers of the solar atmosphere, which are located above the chromosphere. Often during eclipses above the sun surface, you can observe the bizarre forms of "fountains", "clouds", "funnels", "bushes", "arches" and other brightly luminous formation of chromospheric substance. These are the most grandiose formations of the solar atmosphere - Protuberans. They have about the same density and temperature as the chromosphere. But they are above it and are surrounded by higher, strongly sprinkled upper layers of the solar atmosphere. Protubereans do not fall into the chromosphere because their substance is maintained by magnetic fields of active areas of the Sun. Some protuberans, having spent a long time without noticeable changes, suddenly seem to explode, and their substance at a speed of hundreds of kilometers per second is emitted into the interplanetary space.

Unlike the chromosphere and the photosphere, the most outer part of the atmosphere of the Sun - the Crown - has a huge length: it extends more than millions of kilometers, which corresponds to several solar radius. The density of the substance in the solar crown decreases with a height of much slower than air density in the earth's atmosphere. The crown is best observed during the full phase of the solar eclipse. The main feature of the crown is a radiant structure. Coronal rays have the most diverse form: sometimes they are short, sometimes long, there are rays straight, and sometimes they are very curved. General form The solar crown changes periodically. This is due to the eleven-year-old solar activity cycle. Changes both the overall brightness and the shape of the solar crown. In the era of the maximum of solar spots, it has a relatively rounded form. When the stains are not enough, the shape of the crown becomes elongated, while the overall brightness of the crown decreases. So, the crown of the Sun is the most external part of its atmosphere, the most sparse and the hottest. We add that she and the closest to us: it turns out, it extends away from the sun in the form of a constantly moving plasma flow from him - solar wind. In fact, we live surrounded by the solar crown, although protected from its penetrating radiation with a reliable barrier in the form of an earth's magnetic field.

When we see a sunny summer landscape, it seems to us that the whole picture as if filled with light. However, if you look at the sun using special devices, we will find that the entire surface is reminded by a giant sea, where fire waves will be laughed and stains move. What are the main components of the solar atmosphere? What processes occur inside our stars and what substances enter into its composition?

common data

The sun is a heavenly body, which is a star, and the only one in the solar system. Planets, asteroids, satellites and other space objects rotate around it. The chemical composition of the Sun is about the same at any point. However, it changes significantly as the star approaches the center, where its core is located. Scientists have found that the solar atmosphere is divided into several layers.

What chemical elements are included in the sun

Not always, humanity has placed those data about the sun, which today has science. Once supporters of religious worldview argued that the world is impossible to know. And as a confirmation of his ideas, they led the fact that a person is not given to know what the chemical composition of the sun. However, progress in science convincingly proved the fallacy of such views. Especially advanced scientists in the study of the star after the invention of the spectroscope. The chemical composition of the Sun and Stars scientists are studied using spectral analysis. So, they found out that the composition of our star is very diverse. In 1942, researchers discovered that even gold is present in the sun, although it is not so much.

Other substances

Mainly, the chemical composition of the Sun includes elements such as hydrogen and helium. Their prevalence characterizes the gaseous nature of our star. The content of other elements, for example, magnesium, oxygen, nitrogen, iron, calcium is slightly.

With the help of spectral analysis, researchers found out what substances are not exactly on the surface of this star. For example, chlorine, mercury and boron. However, scientists suggest that these substances, in addition to the main chemical elements, which are part of the Sun can be in its core. Almost 42%, our star consists of hydrogen. Approximately 23% accounted for all metals that are in the sun.

Like most of the parameters of other celestial bodies, the characteristics of our star are calculated only theoretically with the help of computing technology. As initial data, such indicators are as the radius of the star, the mass and its temperature. Currently, scientists have determined that the chemical composition of the Sun is represented by 69 elements. Spectral analysis plays a large role in these studies. For example, thanks to him, the composition of the atmosphere of our star was established. An interesting pattern was also discovered: a set of chemical elements in the composition of the sun is surprisingly similar to the composition of stone meteorites. This fact is an important evidence that these heavenly bodies have a general origin.

Fire Crown

It is a layer of a strongly rareered plasma. Its temperature reaches 2 million Kelvinov, and the density of the substance exceeds the density of the earth's atmosphere hundreds of millions of times. Here, atoms cannot be in a neutral state, they constantly face and ionize. The crown is a powerful source of ultraviolet radiation. Our entire planetary system is exposed to solar wind. Its initial speed is equal to almost 1 thousand km / s, but as it removes from the star, it gradually decreases. The speed of the solar wind at the surface of the earth is approximately 400 km / s.

General ideas about the crown

Sunny crown is sometimes called the atmosphere. However, it is only its ourselves. The easiest of all the crown is observed during a complete eclipse. Nevertheless, it will be very difficult to sketch, because the eclipse lasts only a few minutes. When the photo was invented, astronomers were able to get an objective view of the solar crown.

Already after the first pictures were made, the researchers managed to detect areas that are associated with the increased activity of the star. The crown of the sun has a radiant structure. It is not only the hottest part of his atmosphere, but also in relation to our planet is closest. In fact, we are constantly within it, because the sunny wind penetrates the most distant corners of the solar system. However, from its radiation impact we are protected by the Earth's atmosphere.

Core, chromosphere and photosphere

The central part of our star is called the core. Its radius is about a quarter of the total sun radius. The substance inside the nucleus is very compressed. Closer to the surface of the star is the so-called convective zone, where there is a motion of a substance that generates a magnetic field. Finally, the visible surface of the sun is called a photosphere. It is a layer of more than 300 km thick. It is from the photosphere to the Earth comes solar radiation. Its temperature reaches approximately 4,800 kelvins. Hydrogen here is preserved almost in a neutral state. A chromosphere is located above the photosphere. Its thickness is about 3 thousand km. Although the chromosphere and the crown of the Sun are above the photosphere, scientists do not spend clear boundaries between these layers.

Protuboyrans

The chromosphere has a very low density and radiation is inferior to the solar crown. However, here you can observe an interesting phenomenon: the gigantic flames whose height is several thousand kilometers. They are called solar protubers. Sometimes the protuberances rise to a height of a million kilometers above the surface of the star.

Research

Protubereans are characteristic of the same density indicators as the chromosphere. However, they are located directly above it and surround it with sparse layers. For the first time in the history of astronomy, the protuberances were observed by a researcher from France Pierre Zhansen and his English counterpart Joseph Lokimer in 1868 their spectrum includes several bright lines. The chemical composition of the sun and protuberances is very similar. It is mainly represented by hydrogen, helium and calcium, and the presence of other elements is insignificant.

Some protuberans, having existed a certain period of time without visible changes, suddenly explode. Their substance with a giant speed reaching several kilometers per second is thrown into the nearby outer space. Appearance The chromosphere is often changing, which indicates the various processes occurring on the surface of the Sun, including the movement of gases.

In areas of stars with increased activity, not only the protuberances can be observed, but also stains, as well as the amplification of magnetic fields. Sometimes with the help of special equipment in the sun, outbreaks of particular dense gases are found, the temperature of which can reach huge variables.

Chromospheric flashes

Sometimes the radio emission of our star increases hundreds of thousands of times. Such a phenomenon is called chromospheric flash. It is accompanied by the formation of spots on the surface of the sun. First, the flashes were seen as an increase in the brightness of the chromosphere, but subsequently it turned out that they are a whole complex of various phenomena: a sharp increase in radio emission (X-ray and gamma radiation), ejection of mass from the crown, proton flares.

We draw conclusions

So, we found out that the chemical composition of the Sun is represented mostly by two substances: hydrogen and helium. Of course, there are other elements, but their percentage is low. In addition, scientists did not discovered any new chemicals that would be part of the star and there would be no absent on Earth. In the solar photosphere, the formation of visible radiation. It, in turn, has tremendous importance for maintaining life on our planet.

The sun is a hot body that continuously emits its surface is surrounded by a cloud of gases. Their temperature is not as high as the gases inside the star, however it is impressive. Spectral analysis allows you to find out what the chemical composition of the sun and stars. And since the spectra of many stars are very similar to the spectra of the Sun, this means that their composition is about the same.

Today, the processes occurring on the surface and inside the main shone of our planetary system, including studying it chemical compositionLearn astronomers in special solar observatory.

Protuboyrans

The surface of the Sun, which we see, is known as a photosphere. This is an area where light from the kernel finally reaches the surface. The photosphere temperature is about 6000 K, and it glows with white light.

Right over the photosphere, the atmosphere extends several hundred thousand kilometers. Let's consider the building of the atmosphere of the sun.

The first layer in the atmosphere has a minimal temperature, and is located at a distance of about 500 km above the surface of the photosphere, with a temperature of about 4000 K. For the star it is quite cool.

Chromosphere

The next layer is known as a chromosphere. It is only about 10,000 km from the surface. At the top of the chromosphere, the temperature can reach 20,000 K. The chromosphere is invisible without special equipment, which uses narrowband optical filters. Giant solar protubers can rise in a chromosphere to a height of 150,000 km.

Above chromosphere is a transition layer. Below this layer, gravity is the dominant force. Over the transition region, the temperature rises quickly, because helium becomes completely ionized.

Solar crown

The next layer is a crown, and it spreads from the sun to millions of kilometers in space. You can see the crown during a complete eclipse when the disc drive is closed by the moon. The temperature of the crown is about 200 times the hot surface.

While the temperature of the photosphere is only 6000 K, the crown can reach 1-3 million degrees Kelvin. Scientists still do not fully know why it is so high.

Helliosphere

The upper part of the atmosphere is called Heliosphere. This is a bubble of space filled with solar wind, it extends about 20 astronomical units (1 AE. This is the distance from the ground to the Sun). Ultimately, the heliosphere is gradually moving into an interstellar medium.