Stars are the most different: small and large, bright and not very, old and young, hot and cold, white, blue, yellow, red, etc.

To understand the classification of stars allows the Herzshprung chart - Russell.

It shows the relationship between the absolute star magnitude, the luminosity, the spectral class and the temperature of the star surface. Stars on this diagram are not accidentally located, but form good distinguishable areas.

Most of the stars are on the so-called the main sequence . The existence of the main sequence is due to the fact that the hydrogen burning step is ~ 90% of the time of the evolution of most stars: the burnout of hydrogen in the central areas of the star leads to the formation of an isothermal helium nucleus, the transition to the stage of the red giant and the care of the star from the main sequence. About brief evolution Red giants, depending on their mass, to the formation of white dwarfs, neutron stars or black holes.

Being at various stages of its evolutionary development, the stars are divided into normal stars, the stars of dwarf, the stars of giants.

Normal stars, this is the stars of the main sequence. These include our sun. Sometimes such normal stars like the sun are called yellow dwarfs.

Yellow dwarf

Yellow dwarf - type of small stars of the main sequence having a mass from 0.8 to 1.2 mass of the Sun and surface temperature 5000-6000 K.

The lifetime of yellow dwarf is an average of 10 billion years.

After the whole stock of hydrogen burns, the star increases many times in size and turns into a red giant. An example of this type of stars can be Aldebaran.

The red giant throws out the external gas layers, thereby forming planetary nebula, and the kernel collaps into a small, dense white dwarf.

Red giant is a large star of reddish or orange. The formation of such stars is possible both at the stage of star formation and in the later stages of their existence.

At the early stage, the star radiates due to the gravitational energy highlighted in compression, until the compression is stopped by the beyond thermonuclear reaction.

In the later stages of the evolution of stars, after the burnout of hydrogen in their depths, the stars move from the main sequence and move to the region of the red giants and supergigants of the Herzshprung chart - Russell: this stage lasts about 10% of the time "active" life of stars, that is, the stages of their evolution In the course of which Nucleosynthesi reactions go in star departments.

The star giant has a relatively low surface temperature, about 5000 degrees. A huge radius reaching 800 solar and due to such large sizes is a huge luminosity. The maximum radiation falls on the red and infrared range of the spectrum, because they are called red giants.

The largest giants turn into red supergigants. The star called Bethelgeuse from the Constellation Orion is the brightest example of red supergigant.

The stars of dwarfs are the opposite of giants and can be the following.

White dwarf is what remains of the usual star with a mass that does not exceed 1.4 solar masses, after it passes the stage of the red giant.

Due to the lack of hydrogen, the thermonuclear reaction in the kernel of such stars does not occur.

White dwarfs are very dense. In size, they are not more than land, but they can be compared with the mass of the sun.

This is incredibly hot stars, their temperature reaches 100,000 degrees and more. They shine at the expense of their remaining energy, but over time it ends, and the kernel cools, turning into black dwarf.

Red dwarfs are the most common starry-type objects in the universe. Assessment of their number varies in the range from 70 to 90% of the number of all stars in the galaxy. They are quite different from other stars.

The mass of red dwarfs does not exceed a third of the solar mass (the lower mass limit is 0.08 solar, then brown dwarfs), the surface temperature reaches 3500 K. Red dwarfs have spectral class M or Late K. Stars of this type emit very little light, sometimes 10,000 times less than the sun.

Given their low radiation, none of the red dwarfs is visible from the ground with a naked eye. Even the closest to the Sun. Red Dwarf proxima Centauri (the closest star in the triple system) and the nearest single red dwarf, barnard star, have an apparent star magnitude of 11.09 and 9.53, respectively. At the same time, the unarmed look can be observed a star with a star magnitude to 7.72.

Due to the low flow rate of hydrogen, red dwarfs have a very greater life expectancy - from tens of billions to tens of trillion years (red dwarf with a mass of 0.1 mass of the Sun will burn 10 trillion years).

In red dwarfs, thermonuclear reactions involving helium are impossible, so they cannot turn into red giants. Over time, they gradually shrink and are increasingly heated until the entire supply of hydrogen fuel is consumed.

Gradually, according to theoretical ideas, they turn into blue dwarfs - the hypothetical class of stars, until one of the red dwarfs have yet managed to turn into a blue dwarf, and then in white dwarfs with a helium core.

Brown dwarf - subsidences (with the masses in the range of approximately 0.01 to 0.08 mass of the Sun, or, respectively, from 12.57 to 80.35 masses of Jupiter and a diameter of approximately equal to the diameter of Jupiter), in the depths of which, in contrast From the stars of the main sequence, the reaction of thermonuclear synthesis is not occurring with the conversion of hydrogen in helium.

The minimum temperature of the stars of the main sequence is about 4000 K, the temperature of brown dwarfs lies between 300 to 3000 K. Brown dwarfs throughout their lives are constantly cooled, with the larger than the dwarf, the slower it cools.

Subcaric dwarfs

Subcaric dwarfs or brown subcarlics are cold formations, by mass underlying the limit of brown dwarfs. Their mass is less than about one cell mass of the Sun or, respectively, 12.57 masses of Jupiter, the lower limit is not defined. They are more commonly taken by planets, although to the final conclusion about what to consider the planet, and what - subcaric dwarf science community until it came.

Black Dwarf

Black dwarfs - cooled and as a result, which are not emitted in the visible range of white dwarfs. It is the final stage of the evolution of white dwarfs. The masses of black dwarfs, like the masses of white dwarf, are limited from above 1.4 masses of the sun.

Double Star is two gravitationally related stars, adding around the common center of mass.

Sometimes there are systems from three or more stars, in such a general case the system is called a multiple star.

In cases where such a star system is not too far removed from the ground, the telescope disks separate stars. If the distance is significant, then it is possible to understand that the double star is manifested before the astronomers only on indirect signs - gloss fluctuations caused by periodic eclipses of one star with another and some others.

New star

Stars whose luminosity suddenly increases 10,000 times. The new star is a double system consisting of white dwarf and companion stars located on the main sequence. In such systems, gas from the star gradually flows onto white dwarf and periodically explodes there, causing an outbreak of luminosity.

Supernova

The supernova star is a star that ends up its evolution in a catastrophic explosive process. The flash can be several orders of magnitude more than in the case of a new star. Such a powerful explosion is a consequence of the processes occurring in the star at the last stage of evolution.

Neutron Star

Neutron stars (NZ) are star formations with the masses of about 1.5 solar and dimensions, noticeably smaller than white dwarfs, the typical radius of the neutron star is, presumably, about 10-20 kilometers.

They consist mainly of neutral subatomic particles - neutrons, tightly compressed gravitational forces. The density of such stars is extremely high, it is commensurate, and according to some estimates, it can several times to exceed the average density of the atomic nucleus. One cubic centimeter of substance NZ will weigh hundreds of millions of tons. The force of gravity on the surface of the neutron star is about 100 billion times higher than on Earth.

In our galaxy, according to scientists' estimates, there may be from 100 million to 1 billion neutron stars, that is, somewhere on one to one thousand ordinary stars.

Pulsary

Pulsary - Space sources of electromagnetic emissions coming to the ground in the form of periodic bursts (pulses).

According to the dominant astrophysical model, the pulsars are rotating neutron stars with magnetic fieldwhich is tilted to the axis of rotation. When the Earth enters the cone formed by this radiation, then the radiation pulse can be fixed, repeating through the time intervals equal to the period of the stars. Some neutron stars make up to 600 revolutions per second.

Cefeida

Cefeida - class of pulsating stars with a fairly accurate dependence of the luminosity, named after the star Delta Cefheva. One of the most famous cefeid is a polar star.

The list of the main types (types) stars with their brief characteristicOf course, does not exhaust the entire possible manifold of stars in the universe.

The world of heavenly tel

People for a long time belong to the Sun with love and special respect. After all, in antiquity, they realized that without the sun, it was not a man nor a beast, nor a plant.
The sun is the closest star to the ground. Like a friend of the stars, this is a huge hot heavenly body, which constantly radiates light and warm. The sun is a light source and heat for all living on Earth.

Using information, write digital data into text.
The diameter of the Sun is 109 times larger than the diameter of the Earth. The mass of the sun is 330 thousand times more mass of our planet. The distance from the ground to the Sun is 150 million kilometers. The temperature on the surface of the Sun reaches 6 thousand degrees, and in the center of the Sun - 15 - 20 million degrees.

The man can see about 6 thousand stars in the night sky. Scientists are known many billions of stars.
Stars differ in size, color, brightness.
The color is distinguished by white, blue, yellow and red stars.

The sun refers to yellow stars.

Blue stars are the hottest, then there are white, then - yellow, the coldest - red stars.
The brightest stars, empty 100 thousand times more lightthan the sun. But those who shine a million times weaker than the sun are known.

Distinction

The sun and moving around him the celestial bodies make up the solar system. Build the model of the solar system. To do this, cut out the plane of the model planets and place them in the correct sequence on the cardboard sheet. Sign on the name signs planets and get them on your model.





Sold down the crossword.



open unfilled crossword \u003e\u003e

1. The biggest planet Solar system. Answer: Jupiter
2. The planet having a well-visible rings in the telescope. Answer: Saturn
3. The closest to the sun planet. Answer: Mercury
4. The most distant planet from the sun. Answer: Neptune
5. Planet on which we live. Answer: Earth
6. Planet - a neighbor of land, located closer to the Sun than the Earth. Answer: Venus
7. Planet - a neighbor of land, located on the sun than the earth.
Answer: Mars
8. Planet located between Saturn and Neptune. Answer: Uranus

Using various sources of information, prepare a message about the star, constellation or planet that you would like to learn more about. Record the basic information for your message.

Mars - One of the five planets of the solar system, which can be seen from the ground with a naked eye. From the ground, it looks like a small red point, so Mars is sometimes called the red planet. The planet bears the name of the ancient Roman God of war, she has two satellites Phobos and Dimimos. These are the names of the two sons of God of war, they are transferred as "fear" and "horror." Mars is the fourth planet from the sun. For many characteristics, he is very similar to Earth. It has an atmosphere, the time of year is shown on Mars. On both poles of the planet, as on earth, are ice hats. The size of Mars is almost two times less than our planet.

We never think that it is possible to have some kind of life except our planet, except for our solar system. Perhaps some of the planets rotating around blue or white or red, and maybe a yellow star has a life. Perhaps there is another same planet the Earth on which the same people live, but we still do not know anything about it. Our companions, telescopes found a series of planets, which may have a life, but dozens of thousands of thousands and even millions of light years.

Blue Stars Retained - Blue Stars

Stars that are in the stellar columns of the ball type, the temperature in which above the temperatures of ordinary stars, and for the spectrum is characterized by a significant shift to the blue area than the stars of the accumulation with similar luminosity, the blue stars have been named. This feature allows them to stand out relative to other stars of this accumulation on the Herzshprung-Russell diagram. The existence of such stars refutes all the theories of the evolution of stars, the essence of which is that for stars that arose in the same period of time, it is planned to be placed in a clearly defined area of \u200b\u200bthe Herzshprung-Russell diagram. At the same time, the only factor that affects the exact location of the star is its initial mass. The frequent appearance of the blue retired stars beyond the limits of the aforementioned curve may be a confirmation of the existence of such a concept as an abnormal star evolution.

Experts trying to explain the nature of their occurrence have nominated several theories. The most likely of them indicates that the data of the blue color stars in the past were double, after which they began to occur or the merge process now began. The result of the fusion of two stars becomes the emergence of a new star having a much larger mass, brightness and temperature than stars of the same age.

If the loyalty of this theory is able to somehow prove, the theory of star evolution would lose their problems in the form of blue retired. As part of the resulting star, there would be a larger amount of hydrogen, which would lead himself similar to the young star. There are facts confirming such theory. Observations have shown that most often the stars are most often found in the central regions of ball clusters. As a result of the number of stars of a single volume prevailing there, close passages or collisions become more likely.

To verify this hypothesis, it is necessary to study the ripple of blue retired, because There may be some differences between the astrosheyshemical properties of the sprawling stars and normally pulsating variables. It is worth noting that it is difficult to measure pulsations. This process also negatively overcrowding the starry sky, small oscillations of pulsations of blue retired, as well as the rarity of their variables.

One of the examples of the merger could be observed in August 2008, then such an incident touched the object V1309, whose brightness increased several tens of thousands of times, and after several months, returned to the initial meaning. As a result of 6-year observations, scientists came to the conclusion that this object is two stars, the period of circulation of which each friend is 1.4 days. These facts pushed scientists to the idea that in August 2008 there was a merger process of these two stars.

For blue retarded characteristic is the high rotational moment. For example, the speed of rotation of the star, which is located in the middle of the cluster 47 of the Tukanan, is 75 times the speed of rotation of the sun. According to the hypothesis, their mass is 2-3 times higher than the mass of other stars, which are located in the cluster. Also, with the help of research, it was found that if the blue-color stars are close to any other stars, then the latter will have the percentage of oxygen and carbon lower than that of the neighbors. Presumably, the stars are pulling these substances from others moving along their orbit, resulting in their brightness and temperature. The "reserved" stars are found places where the process of turning the initial carbon in other elements occurred.

Blue Star Names - Examples

Rigel, Gamma Sails, Alpha Giraffe, Zeta Orion, Tau Big PSA, Jet stern

White Stars - White Stars

Friedrich Bessel, who led the Koenigsberg Observatory, in 1844 an interesting discovery was made. The scientist noticed the slightest deviation of the brightest star of the sky - Sirius, from his trajectory in the sky. Astronomer suggested the presence of a sirium in Sirius, and also calculated the approximate period of the stars around their center of the masses, which amounted to about fifty years. Bessel did not find due support from other scientists, because Satellite no one could detect, although by its mass he had to be comparable to Sirius.

And after 18 years, Alvan Graham Clark, who was engaged in testing the best telescope of those times, a dull white star was discovered next to Sirius, which turned out to be his companion who called Sirius V.

The surface of this star is white is warm up to 25 thousand Kelvinov, and its small radius. Given this, scientists concluded that the high density of the satellite (at the level of 106 g / cm 3 3, while the density of the sirium itself is approximately 0.25 g / cm 3, and the Sun is 1.4 g / cm 3). After 55 years (in 1917), another White Dwarf was opened, called in honor of the scientist who found him - the star Wang Mansen, which is in the constellation of fish.

White Star Names - Examples

Vega in the constellation Lyra, Altair in the constellation of the Eagle, (visible in summer and autumn), Sirius, Castor.

Yellow stars - yellow stars

Yellow dwarfs are customary to call small stars of the main sequence, the mass of which is within the mass of the sun (0.8-1.4). If you judge by the name, then such stars have a yellow glow, which is allocated during the implementation of the thermalide process of synthesis of hydrogen helium.

The surface of such stars is heated to a temperature of 5-6 thousand Kelvinov, and their spectral classes are in the range between G0V and G9V. Yellow dwarf lives about 10 billion years old. The combustion of hydrogen in the star becomes the cause of its multiple increase in size and transformation into the red giant. One example of the Red Giant is Aldebaran. Such stars can form planetary nebula, getting rid of the outer layers of gas. In this case, the transformation of the kernel in white dwarf, which has a large density.

If you take into account the Herzshprung-Russell diagram, then yellow stars are in the central part of the main sequence. Since the sun can be called typical yellow dwarf, its model is quite suitable for consideration by the general model of yellow dwarfs. But there are other characteristic yellow stars in the sky, whose names are Alhita, Dhabih, Toliman, Hara, etc. Star data do not have high brightness. For example, the same Toliman, which, if not to take into account the proxy centaur, is closer to the Sun, it has a 0th value, but at the same time its brightness is the highest among all yellow dwarfs. This star is located in the Centauro Constellation, it is also the link of a complex system, which consists of 6 stars. The spectral class of Toliman - G. But Dubih, located in 350 light years from us relates to the spectral class F. But its high brightness is due to the presence of a number of stars belonging to the spectral class - A0.

In addition to Toliman, the spectral class G has HD82943, which is located on the main sequence. This star, due to the chemical composition and temperature similar to the Sun, also has two large-sized planets. However, the form of data orbits of the planets is far from circular, so relatively often occur their rapprochement with HD82943. Currently, astronomers were able to prove that earlier this star had a much larger number of planets, but over time she was completely absorbed.

Yellow Star Names - Examples

Toliman, Star HD 82943, Hara, Dhai, Alhita

Red Stars - Red Stars

If you at least once in your life I have been able to see in the lens of your telescope Red stars in the sky that burned on a black background, then the memory of this moment will help more clearly imagine what it will be written in this article. If you never seemed to have similar stars, next time, be sure to find them.

If you take a list of the most bright red stars of the sky, which can be easily found even with the help of an amateur telescope, then you can find that they are all carbon. The first red stars were open back in 1868. The temperature of such red giants is low, in addition, their external layers are filled with a huge amount of carbon. If previously similar stars accounted for two spectral classes - R and N, now scientists have identified them into one common class - C. Each spectral class exists subclasses - from 9 to 0. In this case, C0 class indicates that the star has a larger temperature, but Less red than Stars class C9. It is also important that all the stars are in the composition of the carbon prevailing, inherently variables: long-period, half-way or incorrect.

In addition, two stars called in red semi-butter variables were also included in such a list, the most famous of which is M Cief. Its unusual red was interested in William Herschel, who dubbed her "garnet". For such stars, an incorrect change in the luminosity, which can last from a pair of tens to several hundred days of day. Such variable stars refer to the class M (the stars are cold, the surface temperature is from 2400 to 3800 K).

Given the fact that all stars from the rating are variables, it is necessary to make a certain clarity in the notation. It is generally accepted that the red stars are called, which consists of two components - the letters of the Latin alphabet and the name of the constellation of the variable (for example, t hail). The first variable, which was discovered in this constellation, is assigned the letter R and so on, to the letter Z. if there are many such variables, the double combination of Latin letters is provided for them - from RR to Zz. This method allows you to "call" 334 objects. In addition, you can designate the stars and with the letter V in conjunction with the sequence number (V228 swan). The first rating column is assigned to the designation of variables.

The two following columns in the table indicate the location of stars in the period 2000.0 year. As a result of the increased popularity of the Atlas "Uranometria 2000.0" among astronomy lovers, the last rating column displays the search card number for each star that is in the ranking. In this case, the first digit is the display of the volume number, and the second is the sequence number of the card.

Also in the ranking displays the maximum and minimum gloss values \u200b\u200bof star values. It is worth remembering that the large saturation of the red color is observed from the stars whose brightness is minimal. For stars, the variability of which is known, it is displayed as the number of days, but the objects that do not have the right period are displayed as IRR.

To find a carbon star, you don't need a big skill, enough to have the capabilities of your telescope to see it. Even if its size is small, its brightly pronounced red should attract your attention. Therefore, it is not necessary to get upset if it is impossible to immediately detect them. It is enough to take advantage of the atlas to find a short-range star, and then, move from it to red.

Different observers see carbon stars differently. Some of them resemble rubies or burning in the distance of the corner. Others are seen in such stars raspberry or blood-red shades. To start in the ranking there is a list of six brightest red stars, finding and which, you can enjoy the beauty to enjoy their beauty.

Names of red stars - examples

Differences of Stars in Color

There is a huge variety of stars with indescribable color shades. As a result, even one constellation received the name "Jewelry Jewelry Box", the basis of which is blue and sapphire stars, and in his center there is a bright luminous orange star. If we consider the sun, it has a pale yellow color.

Direct factor affecting the difference in color stars is the temperature of their surface. This is simply explained. Light by nature is radiation in the form of waves. The wavelength is the distance between its crests, is very small. To imagine her, you need to share 1cm per 100 thousand identical parts. Several such particles and will be the wavelength of light.

Given that this number is quite small, each, even the most insignificant, its change will be the reason why the picture observed by us will change. After all, our vision is a different length of light waves perceives as different colors. For example, blue color have waves, the length of which is 1.5 times less than that of red.

Also, almost each of us knows that the temperature can have the most direct effect on the color of the tel. For example, you can take any metal object and put it on fire. During heating, it will become red. If the temperature of the fire increased significantly, the color of the subject would change - with red to orange, with orange on yellow, with yellow on white, and finally, with white on blue-white.

Since the sun has surface temperature in the region of 5.5 thousand 0 s, then it is a characteristic example of yellow stars. But the most hot blue stars can warm up to 33 thousand degrees.

Color and temperatures were associated with scientists with physical laws. The body temperature is directly proportional to its radiation and inversely proportional to the wavelength. Blue waves have shorter wavelengths in comparison with red. The hot gases emit photons whose energy is directly proportional to the temperature and inversely proportional to the wavelength. That is why for the hottest stars characteristic is a blue-blue radiation range.

Since nuclear fuel on the stars is not limitless, it has a property to be consumed, which leads to the cooler of stars. Therefore, middle-aged stars have a yellow color, and the old stars we see red.

As a result of the fact that the sun is very close to our planet, it is possible to describe its color with accuracy. But for stars that are in a million light years from us, the task is complicated. It is for this that the device called the spectrograph is used. Throughout it, scientists skip the light emitted by the stars, as a result of which you can spectally analyze almost any star.

In addition, with the help of a star color, you can determine its age, because Mathematical formulas allow you to use spectral analysis to determine the temperature of the star, which is easy to calculate its age.

Video Secrets Stars Watch Online

Each person knows how stars look in the sky. Tiny, shining with cold snow-white lights. In antiquity, people could not come up with explanations for this phenomenon. Stars considered the eyes of the gods, souls of the dead ancestors, keepers and intercessors who guard the peace of man in the night darkness. Then no one thought that the sun was also a star.

Many centuries passed before people understood that they were stars. Types of stars, their characteristics, ideas about chemical and physical processes occurring there are new Region. knowledge. Ancient astrologists could not even assume that such a luminous was actually not a tiny light, but unimaginable sizes a ball of hot gas, in which the reactions of thermonuclear synthesis occur. There is a strange paradox in the fact that the lack of star light is a dazzling shine nuclear reaction, and cozy solar heat is the monstrous heat of millions of Kelvinov.

All stars that can be seen on the sky with a naked eye are in the Milky Way Galaxy. The sun is also part of this star system, and it is located on its outskirts. It's impossible to imagine yourself how the night sky would look if the sun was in the center Milky Way. After all, the number of stars in this galaxy is more than 200 billion.

A little about the history of astronomy

The oldest astrologers could also tell the unusual and fascinating about the stars in the sky. Already, Sumerians allocated separate constellations and a zodiacal circle, they also calculated the division of a full angle to 3600. They also created moon calendar and were able to synchronize it with sunny. The Egyptians believed that the Earth was in the center of the Universe, but at the same time they knew that Mercury and Venus were spinning around the sun.

In China, astronomy, as a science, they were already engaged in the end of the III Millennium BC. er, and the first observatory appeared in the XII century. BC e. They studied lunar and solar eclipses, at the same time to understand their reason and even having calculated the forecast dates, the meteorological flows and trajectories of Comet were observed.

The most ancient Inca knew differences between stars and planets. There are indirect confirmations that they were known to the Galilean satellites of Jupiter and the visual blur of the outlines of the Venus disk, due to the presence on the planet of the atmosphere.

Antique Greeks were able to substantiate the shag-formation of the Earth, put forward the assumption about the helium-centeredness of the system. They tried to calculate the smoke of the Sun, let and mistakenly. But the Greeks were the first to those who, in principle, suggested that the sun is greater than the Earth, before everything, relying on visual observations, believed differently. Greek Hiparch for the first time created the catalog Luminous and allocated different types of stars. Systematization of stars in this scientific labor Rely on the intensity of the glow. Hipparch highlighted 6 brightness classes, there were 850 luminaries in the catalog.

What did antique astrologers draw

Initial systematization of stars was based on their brightness. After all, specifically, this criterion is the only easily accessible for the astrologer, armed only by a telescope. The brightest either possessing unique visible stars properties even received their own names, and each people they have their own. So, Denb, Rigel and Algol - Arabic names, Sirius - Latin, and Antares - Greek. The polar star in each people has its own name. This is perhaps one of the most principled in the "practical sense" of stars. Its coordinates at the night sky are unchanged, despite the rotation of the Earth. If the remaining stars move across the sky, passing the way from sunrise to sunset, the polar star does not change its location. Therefore, it was specifically used by sailors and travelers as a reliable reference point. By the way, contrary to common misconception, it's not the most bright Star in the sky. The polar star outside does not stand out - neither size nor the intensity of the glow. You can find it only if you know where to watch it. It is located at the very end of the "Arm of the Bucket" of the Small Malar.

What is the basis of star systematization

Modern astrologers, answering the question of which types of stars are, the brightness of the glow or the location at the night sky will be mentioned. Is that in the order of a historical excursion either in a lecture calculated on the audience completely distant from astronomy.

Modern systematization of stars is based on their spectral analysis. At the same time, they usually also indicate the mass, luminosity and radius of the celestial body. All these indicators are given in the ratio with the Sun, that is, specifically its characteristics are taken as units of measurement.

Systematization of stars is based on such a criterion as an absolute star value. This is the visible degree of brightness of the celestial body without the atmosphere, conditionally located at a distance of 10 parses from the observation point.

In addition, it takes into account the variability of the brilliance and the size of the star. Types of stars are currently determined by their spectral class and is already more detailed - subclass. Astrologers Russell and Herzshprung independently of each other analyzed the dependence between the luminosity, the absolute star magnitude, the temperature surface and the spectral class of shone. They built a diagram with the corresponding axes of coordinates and found that the result is not at all chaotided. The luminaries on the chart were distinctly distinguished groups. The diagram allows, knowing the spectral class of the star, determine at least with an approximate accuracy of its absolute star magnitude.

How stars are born

This diagram served as visual confirmation in favor. modern theory The evolution of these celestial bodies. The graph clearly shows that the most numerous class is related to the so-called the main sequence of the star. Types of stars belonging to this segment are in the most common at this point in the Universe Development Point. This stage of development of the shine, in which the energy spent on the radiation is compensated by the resulting in the process of thermonuclear reaction. The duration of stay at this stage of development is determined by the mass of the celestial body and the percentage of elements heavier than helium.

The theory of stars generally recognized at this moment says that at the initial stage of development, the luminais is a discharged cyclopic gas cloud. Under the influence of one's own burden, it is compressed, gradually turning into a ball. The stronger the compression, the better the gravitational energy goes into thermal. Gas is late, and when the temperature achieves 15-20 million k, the alemonuclear reaction is launched in a newborn star. After that, the gravitational compression process is suspended.

The main period of life of the star

At first, the reactions of the hydrogen cycle prevail in the depths of a young shone. This is the longest star life. Types of stars located at this stage of development, and are represented in the most mass major sequence described above the diagram. With the times, hydrogen in the nucleus of the shine is completed, turning into helium. After that, thermonuclear combustion can only be on the periphery of the kernel. The star becomes brighter, its outer layers are significantly expanding, and the temperature decreases. Heavenly body turns into a red giant. This period of life is much shorter than the previous one. The upcoming fate is seriously studied. There are various assumptions, but they have not yet been accompanied by confirmation. The most common theory says that when helium becomes too much, the starry core, without holding its own mass, shrinks. The temperature grows until helium enters the thermonuclear reaction. Monstrous temperatures lead to another expansion, and the star turns into a red giant. The upcoming fate of the shone, on the assumptions of scientists, is depending on its mass. But theories relating to this, just the result of computer simulation, not confirmed by observations.

Cooled stars

Presumably, the red giants with a small mass will shrink, turning into dwarfs and gradually cooling. The middle mass stars can transform into planetary nebulae, while in the center of such education will continue its existence of an external cover of the kernel, gradually cooling and turning into a snow-white Liliput. If the central star emitted substantial infrared radiation, the conditions for activation in the expanding gas shell of the planetary nebula of the cosmic Maser appear.

Massive luminaries, compressing, can reach this level of pressure that electrons are practically ground in atomic nuclei, turning into neutrons. Because there are no electrostatic repulsions between these particles, the star can be sized up to the size of several km. In this case, its density exceeds the density of water 100 million times. Such a star is called neutron and is, in fact, a huge atomic core.

Supermassive stars continue their existence, sequentially synthesizing in the process of thermonuclear reactions from helium - carbon, then oxygen, from it - silicon and, finally, iron. At this stage of the thermonuclear reaction and a supernova explosion occurs. Supernovae, in turn, can turn into neutron or if their mass is quite large, continue compression to a critical limit and form black holes.

Dimensions

Systematization of stars in size can be implemented double. The physical size of the star can be determined by its radius. The unit of measurement in this case protrudes the radius of the Sun. There are Liliputs, high-size stars, giants and supergiant. By the way, the sun itself is just a Liliput. The radius of neutron stars can reach only a few km. And the Orbit of the planet Mars is placed entirely in the whole nichrite. Under the size of the star can also be understood its mass. It is closely related to the shone diameter. The star is more, the lower its density, and vice versa, than the lumplement less, the density is higher. This criterion is viring not so much. Stars that could be more or less than the sun 10 times, very little. Most of the luminaries are placed in an interval from 60 to 0.03 of the solar masses. The density of the sun, received for the starting indicator, is 1.43 g / cm3. The density of snow-white dwarfs is achieved 1012 g / cm3, and the density of rarefied supergiant can be in millions of times less solar.

In the standard systematization of stars, the mass distribution scheme is as follows. Small referred to luminous with a mass of 0.08 to 0.5 solar. To moderate - from 0.5 to 8 solar masses, and to massive - from 8 and more.

Systematization of stars . From blue to snow-white

The systematization of the stars in color actually relies not on the visible glow of the body, but on the spectral characteristics. The object radiation spectrum is determined by the chemical composition of the stars, its temperature depends on it.

The most common is Harvard systematization, created first of the 20th century. According to the following standards, the systematization of stars in color implies division into 7 types.

So, the stars with the highest temperature, from 30 to 60 thousand k, refer to the luminas class O. They are blue, the mass of such celestial bodies achieves 60 solar masses (s. M.), And radius - 15 solar radius (p. R.). The lines of hydrogen and helium in their spectrum are rather weak. The luminosity of such celestial objects can reach 1 million 400 thousand solar luminosities (s. P.).

Class B stars include shone with a temperature of from 10 to 30 thousand K. These are the celestial bodies of white and blue, their mass begins from 18 s. m., but radius - from 7 s. m. The lowest luminosity of objects of this class is 20 thousand s. p., And hydrogen lines in the spectrum are enhanced by reaching medium values.

In stars of class and the temperature ranges from 7.5 to 10 thousand to, they are snow-white. The minimum mass of such celestial bodies starts from 3.1 s. m., but radius - from 2.1 s. R. The luminosity of objects is within the borders from 80 to 20 thousand s. from. The hydrogen lines in the spectrum of these stars are strong, metal lines appear.

Class F objects are actually yellow-white, but looks snow-white. Their temperature ranges from 6 to 7.5 thousand k, the mass varies from 1.7 to 3.1 S.M., radius - from 1.3 to 2.1 s. R. The luminosity of these stars varies from 6 to 80 s. from. The hydrogen lines in the spectrum weaken, the metal lines, on the contrary, are amplified.

Thus, all types of snow-white stars fall within the classes from A to F. Next, according to the systematization, the yellowish and orange luminas are followed.

Yellowish, Orange and Red Stars

Types of stars in color are distributed from blue to red, as temperature drops and reduce the size and luminosity of the object.

The stars of class G, to which the sun applies, achieve temperatures from 5 to 6 thousand k, they are yellowish. The mass of such objects is from 1.1 to 1.7 s. m., radius - from 1.1 to 1.3 s. R. Luminativity - from 1.2 to 6 s. from. Spectral lines of helium and metals are intense, hydrogen lines are weaker.

The luminaries relating to the class K, have a temperature of from 3.5 to 5 thousand. K. They look yellow-orange, but the real color of these stars is orange. The radius of these objects is between 0.9 to 1.1 s. r., Mass - from 0.8 to 1.1 s. m. Brightness ranges from 0.4 to 1.2 s. from. Hydrogen lines are almost invisible, metal lines are very strong.

The coldest and small stars are class M. Their temperature is only 2.5 - 3.5 thousand to and they seem red, although in fact these objects of orange-red. The mass of the stars is between 0.3 to 0.8 s. m., radius - from 0.4 to 0.9 s. R. The luminosity is only 0.04 - 0.4 s. from. These are dying stars. Their colder is only recently open brown liliputs. For them allocated a separate class Mr.

Three aggregate states of the substance are known - solid, liquid and gaseous. What will happen to a substance with consistent heating to high temperatures in a closed volume? - Sequential transition from one aggregate state to another: body Body - Liquid Gas (due to an increase in the speed of molecules with the increase in temperature). With further heat heating at temperatures above 1,200 ºС, the decay of gas molecules to atoms begins, and at temperatures above 10,000 ºС - partial or complete decay of gas atoms to their components elementary particles - electrons and cores of atoms. Plasma is the fourth state of a substance in which molecules or atoms of the substance are partially or completely destroyed under the action of high temperatures or for other reasons. 99.9% of the substance of the Universe is in a state of plasma.

Stars are a class of cosmic bodies with a mass of 10 26 -10 29 kg. Star is a split plasma spherical cosmic body, as a rule, in hydrodynamic and thermodynamic equilibrium.

If the equilibrium is broken, the star begins to pulsate (its size, luminosity and temperature change). Star becomes a variable star.

Variable star - This is a star that changes the brilliance over time (visible brightness in the sky). The causes of variability may be physical processes in the depths of the star. Such stars are called physical variables (for example, Δ Cepheva. Similar to it, variable stars began to call cepheidami).


Meet I. estimated variables Stars, the cause of the variability of which are mutual eclipses of their components(for example, β Persea - Algole. Her variability first discovered the Italian economist and astronomer Geminian Montanari in 1669).


Stretch-variable stars are always double, those. Consist of two closely arranged stars. Variable stars on star maps are indicated by a circle:

Not always stars - balls. If the star rotates very quickly, then its shape is not a spherical. The star is compressed from the poles and becomes similar to the mandarin or pumpkin (for example, Vega, Regul). If the star is double, then the mutual attraction of these stars to each other also affects their shape. They become egg-shaped or melon (for example, double-star components β lira or spikes):


Stars are the main inhabitants of our galaxy (our galaxy is written with a capital letter). It has about 200 billion stars. With the help of even the biggest telescopes, it is possible to consider only half apler from the total number of galaxy stars. In the stars, more than 95% of the total substance observed in nature are concentrated. The remaining 5% is the interior gas, dust and all non-simulating bodies.

In addition to the Sun, all the stars are from us so far that even in the largest telescopes they are observed in the form of glowing points of different colors and gloss. The nearest to the Sun is the α centaution system, consisting of three stars. One of them is a red dwarf called Proxima - is the closest star. Up to her 4.2 light years. To Sirius - 8.6 sv. years, to Altair - 17 sv. years. Before VEGI - 26 st. years. To the polar star - 830 st. years. Until Deneba - 1,500 sv. years. For the first time, the distance to another star (it was Vega) in 1837 was able to determine V.Ya. Struve.

The first star, who has been able to obtain a disk image (and even some spots on it) - Bethelgeuse (α Orion). But this is because the diameter of Bethelgeuse exceeds the sun 500-800 times (the star pulsates). Altair disk (α α) was also obtained, but this is because Altair is one of the nearest stars.

The color of the stars depends on the temperature of their external layers. Temperature range - from 2,000 to 60,000 ° C. The coldest stars are red, and the hottest is blue. According to the color of the star, it is possible to judge how strongly its external layers are rapid.


Examples of red stars: Antares (α of Scorpion) and Bethelgeuse (α Orion).

Examples of orange stars: Aldebaran (α Taurus), ArkurTur (α Volopasa) and Pollux (β twins).

Examples of yellow stars: the sun, the chapel (α of the eating) and Toliman (α centaution).

Examples of yellowish-white stars: a probe (α of small ps) and canopus (α keel).

Examples of white stars: Sirius (α large PSA), Vega (α lira), Altair (α Eagle) and denb (α swan).

Examples of bluish stars: Regul (α lion) and spice (α virgin).

Due to the fact that very little light comes from the stars, the human eye is able to distinguish between the color shades only in the brightest of them. In binoculars and especially in the telescope (they catch more light than the eye) the color of the stars becomes more noticeable.

With depth, the temperature is growing. Even the coldest stars in the center the temperature reaches millions of degrees. At the sun in the center about 15,000,000 ° C (also used Kelvin scales - the scale of absolute temperatures, but when it comes to very high temperatures, a difference of 273 º between Celvin and Celsius scales can be neglected).

What does the star subsoil warms so much? It turns out, there are happening thermonuclear processesAs a result of which a huge amount of energy is distinguished. Translated from the Greek "Thermos" means warm. The main chemical element from which the stars are hydrogen.It is he who is fuel for thermonuclear processes. In these processes, the nuclei of hydrogen atoms into the core of helium atoms is accompanied, which is accompanied by the release of energy. The number of hydrogen nuclei in the star decreases, and the number of helium nuclei increases. Over time, other chemical elements are synthesized in the star. All chemical elements from which there are molecules of various substances, once in the depths of the stars were born. "Stars are the past of a person, and a person is the future of the stars," it is sometimes figuratively spoken.

The process of emitting the star of energy in the form of electromagnetic waves and particles is called radiation. Stars emit energy not only in the form of light and heat, but also other types of radiation - gamma rays, x-ray, ultraviolet, radio emission. In addition, the stars emit threads of neutral and charged particles. These streams form a star wind. Stellar wind - This is the process of the expiration of the substance from the stars in the outer space. As a result, the mass of the stars constantly and gradually decreases. It is the star wind from the Sun (Sunny Wind) leads to the appearance of polar radiances on earth and other planets. It was the solar wind that deflects the tails of comet in the opposite side of the sun.

Stars appear, naturally, not from emptiness (space between stars is not an absolute vacuum). The material serves gas and dust. They are distributed in space unevenly, forming shapeless clouds of very small density and enormous length - from one to two to dozen light years. Such clouds are called diffuse gas-dust nebula. The temperature in them is very low - about -250 ° C. But the stars are formed in each gas-dust nebula. Some nebulae can exist without stars for a long time. What conditions are needed to start the process of nucleation of stars? The first thing is the mass of the clouds. If the matter is not enough, then, of course, the star will not appear. Second, compactness. In too extended and loose cloud, the processes of its compression can begin. Well, and thirdly, the seed is needed - i.e. The bunch of dust and gas, which will then become an embryo of the stars - the protostar. Protocol - This is a star at the final stage of its formation. If these conditions are observed, the gravitational compression and heating of the cloud begins. This process ends star formation - The appearance of new stars. It takes this process millions of years. The astronomers were found in the nebula, in which the star formation process in full swing - some stars have already lit, some are in the form of embryos - protozoases, and the nebula is still preserved. An example is the big nebula of Orion.

The main physical characteristics of the star are the luminosity, mass and radius (or diameter), which are determined from observations. Knowing them as well chemical composition Stars (which is determined by its spectrum), you can calculate the model of the star, i.e. Physical conditions in its depths, explore the processes that occur in it.Let us dwell on the main characteristics of the stars.

Weight. You can directly evaluate the mass only by gravitational stars on the surrounding bodies. The mass of the Sun, for example, was determined by the famous periods of circulation around it planets. Other stars of the planet are not directly observed. Significant measurement of the mass is possible only in double stars (with a generalized Newton III Law of Kepler, Noh and then the error is 20-60%). Approximately half of all stars in our galaxy - double. Mass stars fluctuate from ≈0.08 to ≈100 mass of the sun.Stars with a mass less than 0.08 mass of the Sun does not happen, they simply do not become stars, but remain dark bodies.Stars weighing more than 100 masses of the Sun are extremely rare. Most of the stars have a mass of less than 5 masses of the sun. The fate of the star depends on the mass, i.e. That scenario for which the star is developing, evolving. Small cold red dwarfs are very economical consumed hydrogen and therefore their lives continues hundreds of billions of years. The lifespan of the Sun - Yellow Dwarf - about 10 billion years (the sun has already lived about half of his life). Massive supercrowders consume hydrogen quickly and fade already a few million years after their birth. The more massive star, the shorter its life path.

The age of the universe is estimated at 13.7 billion years. Therefore, stars age more than 13.7 billion years have not yet exist.

  • Stars with mass 0,08 Sun masses are brown dwarfs; Their fate is constant compression and cooling with the cessation of all thermonuclear reactions and the transformation into dark planet-like bodies.
  • Stars with mass 0,08-0,5 Sun masses (these are always red dwarfs) After the consumption of hydrogen, they begin to slowly shrink, while heating and becoming white dwarf.
  • Stars with mass 0,5-8 The masses of the Sun at the end of life turn first in the red giants, and then in white dwarfs. External stars of the star are dissipated in outer space in the form planetary nebula. Planetary nebula often has the shape of the sphere or ring.
  • Stars with mass 8-10 The masses of the sun can be exploded at the end of life, and can become calmly, first turning into red superdgigants, and then in red dwarfs.
  • Stars with a mass of more 10 The mass of the Sun at the end of the life path is first becoming red supercrutants, then explode like supernovae (a supernova star is not a new one, but an old star) and then turn into neutron stars or become black holes.

Black holes - It is not openings in outer space, but objects (residues of massive stars) with a very large mass and density. Black holes do not have supernatural nor magical forces, are not "monsters of the Universe." They simply have such a strong gravitational field that no radiation (nor the visible light, nor invisible) cannot leave them. Therefore, black holes are not visible. However, they can be detected by their impact on the surrounding stars, nebula. Black holes are a completely ordinary phenomenon in the universe and they should not be scared. In the center of our galaxy, it is possible, there is a supermassive black hole.

Radius (or diameter). Star dimensions vary widely - from several kilometers (neutron stars) to 2,000 diameters of the Sun (supergiant). As a rule, the smaller the star, the higher its average density. In neutron stars, the density reaches 10 13 g / cm 3! Screw such a substance weighed 10 million tons on Earth. But ultra-nucleons have a density less than air density at the surface of the Earth.

Diameters of some stars in comparison with the Sun:

Sirius and Altair 1.7 times more,

Vega 2.5 times more,

Regult is 3.5 times more,

Arcturus is 26 times more

Polar 30 times more

Rigel is 70 times more

Denief 200 times more

Antares 800 times more

YV Big PSA 2,000 times more (the largest star from famous).


The luminosity is the total energy emitted by the object (in this case by the stars) per unit of time. The luminosity of the stars are usually compared with the luminosity of the sun (the luminosity of the stars expressed through the luminosity of the Sun). Sirius, for example, 22 times emits more energy than the sun (Sirius's luminosity is 22 suns). The luminosity of the vegue is 50 suns, and the luminosity of Deneba is 54,000 Suns (Denb is one of the most powerful stars).

Visible brightness (more correct, shine) stars on the earthly sky depends on:

- distances to Star. If the star will approach us, then its visible brightness will gradually increase. And vice versa, when removing the star from us, its visible brightness of little grave will decrease. If you take two identical stars, then close to us will seem more bright.

- from the temperature of the external layers. The stronger the star is riveted, the greater the light energy it sends into space, and the brighter it will seem. If the star cools, then the visible brightness in the sky will decrease. Two stars of the same sizes and at the same distances from us will seem the same by visible brightness, provided that they emit the same amount of light energy, i.e. Have the same temperature of the external layers. If one of the stars is colder than the other, it will seem to be less bright.

- from sizes (diameter). If you take two stars with the same temperature of the external layers (one color) and arrange them at the same distance from us, then a larger star will radiate more light energy, and therefore it will seem brighter in the sky.

- from the absorption of the light by the clouds of cosmic dust and gas on the way of the beam. The thicker layer of cosmic dust, the greater the light from the star it absorbs, and the dull it seems the star. If we take two identical stars and put in front of one of them gas-dust nebula, then this star and will seem less bright.

- from the height of the star over the horizon. There is always a dense haze near the horizon, which absorbs part of the light from the stars. Near the horizon (shortly after sunrise or shortly before the occasion), the stars always look more dull than when they are above the head.

It is very important not to confuse the concepts "seem" and "be". Star can be very bright in itself, but seem Duffen due to various reasons: due to the long distance to it, due to small sizes, due to the absorption of its light of cosmic dust or dust in the atmosphere of the Earth. Therefore, when they talk about the brightness of the star on the earthly sky, they use phrase "Visible brightness" or "glitter".


As already mentioned, there are double stars. But there are also triple (for example, α centaurus), and quadruple (for example, ε lira), and five, and gear (for example, Castor), etc. Separate stars in a star system called components. Stars with the number of components more than two called multiple Stars. All components of a multiple star are connected by mutual gravity (form the stars system) and move through complex trajectories.

If there are many components, then this is no longer multiple star, but star accumulation. Distinguish ball and scattered star clusters. Ball clusters contain many old stars and are more older than clusters scattered, containing many young stars. Ball clusters are quite stable, because The stars in them are at short distances from each other and the strength of the mutual attraction between them is much more than between the stars of scattered clusters. Scattered clusters over time are scattered even more.

Scattered clusters, as proper, are located on the Milky Way Licap or nearby. On the contrary, ball clusters are located on the Star Sky away from the Milky Way.

Some star clusters can be seen in the sky even with a naked eye. For example, scattered accumulations of giad and pleiades (m 45) in the Taurus, scattered cluster of nursery (M 44) in cancer, ball cluster M 13 in Hercules. Quite a lot of them visible in binoculars.