I think it's no secret to anyone that our sun and the stars that we see at night in the sky are the same. That's just the "night" stars are farther away from us than the sun.

Stars- These are huge spherical accumulations of hot gas. As a rule, stars consist of more than 99% from gas, the remaining fractions of a percent account for a huge number of elements (for example, there are about 60 of them in our sun). The temperature of the surfaces of various types of stars ranges from 2,000 to 60,000 degrees Celsius.

What makes stars emit light? Ancient thinkers thought that the surface of the sun was constantly on fire, and therefore radiated light and heat. However, it is not. First, the reason for the emission of heat and light is much deeper than the surface of the star, namely in core. And secondly, the processes occurring in the depths of stars are not at all like combustion.

The process that takes place in the interior of stars is called. In a nutshell, thermonuclear fusion is the process of converting matter into energy, and an incredible amount of energy is released from a minimal amount of matter.

From a scientific point of view, this is a reaction in which lighter atomic nuclei - usually isotopes of hydrogen(deuterium and tritium) merge into heavier nuclei - helium. For this reaction to occur, an incredibly high temperature is required - several million degrees.

This reaction takes place in our sun: at a core temperature of 12,000,000 degrees, 4 hydrogen atoms merge into 1 helium nucleus and an unimaginable amount of energy is released: heat, light and electromagnetism.

How could you guess the sun forever, it will "burn itself" over time. Scientists believe that there is still enough matter in it for about 4-6 billion years, i.e. somewhere as long as it has already existed.

Stars radiate huge amounts of heat and light for many billions of years, which requires a huge amount of fuel consumption. Until the twentieth century, no one could imagine what kind of fuel it was. The biggest problem in physics was the big question - where do stars get their energy from? All we could do was look up into the sky and realize that there was a huge “hole” in our knowledge. To understand the secret of the stars, a new engine of discovery was needed.

Helium was needed to unlock the secret. Albert Einstein's theory proved that stars can get energy from within atoms. The secret of the stars is Einstein's equation, which is the formula E \u003d ms 2. In a sense, the number of atoms that make up our body is concentrated energy, compressed energy, energy compressed into atoms (space dust particles) that make up our universe. Einstein proved that this energy could be released by colliding two atoms. This process is called thermonuclear fusion, it is this force that feeds the stars.

Imagine, but the physical properties of a small, subatomic particle determine the structure of stars. Thanks to Einstein's theory, we have learned how to release this energy inside the atom. Now scientists are trying to simulate the source of stellar energy in order to gain power over the power of fusion in the laboratory.

Inside the walls of the laboratory, near Oxford in England, is the machine that Andrew Kirk and his team are turning into a "star" laboratory. This installation is called Tokamak. It's basically a big magnetic bottle that holds a very hot plasma that can simulate conditions like the inside of a star.

Inside the Tokamak, hydrogen atoms oppose each other. To push the atoms against each other, the tokamak heats them up to 166 million degrees, at this temperature the atoms move so fast that they cannot avoid colliding with each other. Heating is a movement, the movement of heated particles is enough to overcome the repulsive force. Traveling at thousands of kilometers per second, these hydrogen atoms crash into each other and combine to form a new chemical element, helium, and a small amount of pure energy.

Hydrogen weighs a little more than helium, in the process of combustion the mass is lost, the lost mass is converted into energy. A tokamak can support the fusion of a fraction of a second, but in the interior of a star, the fusion of nuclei does not stop for billions of years, the reason is simple - the size of the star.

A star lives by gravity. That's why the stars are big, huge. To compress a star, you need a huge force of attraction in order to release an incredible amount of energy, sufficient for thermonuclear fusion. This is the secret of the stars, this is why they shine.

Synthesis in the core of the sun's star generates every second the power that would be enough for a billion nuclear bombs. A star is a giant hydrogen bomb. Why doesn't it just shatter into pieces then? The fact is that gravity compresses the outer layers of the star. Gravity and synthesis are waging a grand war, the attraction of which wants to crush the star and the energy of fusion, which seeks to blow the star apart from the inside, this conflict and this balance create a star.

This is a struggle for power that continues throughout the life of a star. It is these fights on the stars that create the light and each ray of the stellar journey makes an incredible journey, the light travels 1080 million kilometers per hour. In one second, a beam of light can circle the earth seven times, nothing in the universe moves so fast.

Since most stars are very far away, light travels hundreds, thousands, millions and even billions of years to reach us. When the Hubble orbiting space station peers into the far corners of our universe, it sees light that has traveled for billions of years. The light of the Etequilia star that we see today set off on a journey - 8,000 years ago, the light of Betelgeuse has been flying since Columbus discovered America - 500 years ago. Even the light of the Sun flies to us for as long as 8 minutes.

When the sun synthesizes helium from hydrogen, a particle of light, a photon, is produced. This beam of light has a long and difficult journey to the surface of the Sun. The whole star prevents it, when a photon appears it crashes into another atom, another proton, another neutron, it doesn't matter, it is absorbed, then reflected in a different direction and moving so chaotically inside the Sun, it has to break out.

The photon will have to rush wildly, crash into the atoms of the gas billions of times and desperately rush out. It's funny, in order to get out of the core of the Sun, it takes a photon thousands of years and only 8 minutes to fly from the surface of the Sun to the Earth. Photons are sources of heat and light, thanks to which diverse and amazing life is supported on our planet Earth!

It is calculated that on average the amount of radiation emanating from each square meter of the solar surface is 62 thousand kilowatts, which is approximately equal to the power of the Volkhovskaya hydroelectric power station. The radiation power of the entire Sun is equivalent to the work of 5 billion billion (5 10 18) such power plants!

Let's give one more figure: each square meter of the solar surface emits as much light as 5 million 100-watt light bulbs could give it ... So, tirelessly, our radiant luminary "works" not for centuries or even millennia, but for billions of years !

What happens on the Sun? Where does it continuously draw a truly colossal amount of energy?

In 1920, the eminent English astronomer Arthur Eddington (1882-1944) first suggested that thermonuclear fusion could be the source of solar energy. Subsequently, other scientists developed this idea. According to modern concepts, nuclear reactions take place in the depths of the Sun and similar stars, that is, processes during which not chemical compounds are formed, but the nuclei of new chemical elements. And in the hot bowels of the luminary, where the temperature can reach 15 million degrees, the nuclei of hydrogen atoms - protons, overcoming the force of mutual repulsion, approach each other and, "merging", form helium nuclei. This process of converting hydrogen into helium consists of a chain of three consecutive nuclear interactions, called proton-proton cycle, as a result of which one helium nucleus is formed from four hydrogen nuclei. But the mass of a helium nucleus is somewhat less than the mass of four protons. So, in the synthesis of 1 g of hydrogen, the "mass defect" is 7 mg. Knowing this and using it discovered by Albert Einstein (1879-1955) the law of the relationship of mass and energy, we can calculate that only when "burning" 1 g of hydrogen, 150 billion calories are released! In a solar thermonuclear "boiler", 564 million tons of hydrogen should "burn" every second, that is, turn into 560 million tons of helium. And if half of the remaining hydrogen reserves on the Sun went to thermonuclear fusion, then the Sun would shine and warm the Earth with unrelenting force for another 30 billion years. This means that the thermonuclear process can be that inexhaustible source of solar energy, which for so long could not be established.

Thermonuclear reactions proceed only at temperatures above 10 million degrees. Such a high temperature can dominate only in the most "central" region of the Sun with a radius equal to about a quarter of the solar one. The energy in this self-controlled thermonuclear reactor is released in the form of hard gamma rays.

The "leakage" of radiation from the center of the Sun to the surface is extremely slow. In this case, in the process of energy transfer from layer to layer, gamma quanta are crushed. First, they turn into X-ray quanta, then into ultraviolet ... It will take about 10 million years before the gamma quanta born in the bowels of the star come out of it as photons of visible light. Thus, the light emitted by the Sun today was generated at the end of the Tertiary period, that is, long before the type of modern man appeared on Earth.

But the optical (visible) radiation of the Sun does not reflect the physical essence of the phenomena occurring in the depths of the star. And if so, then solar thermonuclear fusion is just a hypothesis that needs to be proven.

The mass of the Sun is 99.9% of the mass of the entire solar system. The main elements of which it consists are hydrogen (73%) and helium (25%). Other elements include iron, nickel, nitrogen, oxygen, sulfur, silicon, carbon, magnesium, calcium, chromium, neon. The density of the star is low - 1.4 g / cm 3, and its type is a yellow dwarf. If we compare the Sun with, then the ratio of diameter will be 109:1, mass 333,000:1, and volume 1,300,000:1. The age of our luminary is 4.57 billion years.

sunny wind

sunny wind- a continuous stream of plasma of solar origin, propagating from the atmosphere of the Sun and filling the solar system. Due to the high temperature of the solar corona, the pressure of the overlying layers cannot balance the pressure of the corona matter. This substance is ejected into space in the form of the solar wind, spreading to a distance of up to 100 a.u. a.u. - astronomical unit 1 astronomical unit = 149,597,871 kilometers. This is the average distance from the Earth to the Sun.

In the figure, the empty field in the center covers a space 32 times the size of the Sun. The diameter of the image is half the diameter of the orbit. The points behind the sun are the stars.

Why does the sun shine

The glow of the sun- the result of the release of huge energy released as a result of the occurrence of a thermonuclear reaction in its core. Little substance is spent, a lot of energy is released (millions of times more than with conventional combustion).

It used to be believed that the Sun shines due to the burning of the elements that make up its composition. But according to rough estimates, even rough ones, it cannot “burn out” for billions of years, the Sun should have died out quite a long time ago, having lost mass, thereby violating the gravitational balance in the system of planets. But the Sun has been shining for billions of years and is not going to go out anytime soon.

Solar eclipse

A solar eclipse is an astronomical phenomenon in which the Moon completely or partially blocks the Sun from a person on Earth. During an eclipse, the sun's corona can be observed.

supernovae. According to the main theory, the Sun and the solar system formed from a gas and dust cloud, which was precisely the remnant of a supernova explosion.

Several twins of our star are known. They are similar in mass, luminosity, age, and temperature. These are 18 Scorpio, 37 Gemini, Beta Canis Hounds, HD 44594 and HIP56948.

The vital activity of all life on earth is supported by sunlight. He is a source of warmth, growth, development. For many centuries, mankind has been wondering where the endless power comes from in the luminary? Especially what is the cause of such a glow, and how long will it last?

Failed assumptions about the glow of the Sun

For centuries, scientists have been convinced that the Sun is very dense, composed of combustible material and constantly burning. But it is known that no metal, stone or other substance can do this indefinitely. The fire will one day run out.

The age of the red-hot star has long been established. It has been giving light around itself to the planetary system for many billions of years (long before the appearance of the first man). Only the surface temperature is 6000 degrees. It becomes clear that the "fuse" would not be enough until today. It should have been burned to the ground.

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Other planets and planetary systems

Other men of science have looked for the secret of permanent light in the endless collisions of a celestial body with the millions of meteorites that it attracts. But this theory turned out to be wrong. According to strict mathematical calculations, the mass of meteorites significantly exceeded the mass of the Sun in the multibillion-year history of existence. It would have been destroyed by similar bombers.

: The distance from the Earth to the Sun is on average 150 million km. Sunlight overcomes it in 8.3 minutes.

Versions were put forward about the excessive attraction of solar particles, causing compression of the volume of a luminous star. But every time new flaws were revealed.

Only at the beginning of the last century, physicists turned their attention to the internal structure and the processes associated with its features.

The sun is a hot gaseous ball, exceeding the mass of the earth by more than 1.3 million times. In the center is the core, the temperature of which exceeds 15,000,000 degrees. It performs the function of a nuclear reactor. Following from it to the surface, several zones are distinguished: radiative transfer, convective, photosphere, chromosphere, corona. The sun is made up of:

• hydrogen (74%)
• helium (25%)
• another 60 items (approximately 1%).

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Why do the stars shine?

The glow of the sun

With every second, lighter hydrogen is burned in the center, which converts it into heavy helium. For the formation of 1 helium core, the fusion of 4 hydrogen cores is required. This process is identical to the reactions in the atomic bomb, only slower. And it's called thermonuclear fusion.