We live in a galaxy that we call Milky Way. Our planet Earth is just a grain of sand in the Milky Way galaxy. In the course of filling the site, every now and then moments arise that it would seem that I should have written about a long time ago, but were either forgotten, did not have time, or switched to something else. Today we will try to fill one of these niches. Today our topic is the Milky Way galaxy.

Once upon a time people thought that the center of the World was the Earth. Over time, this opinion was recognized as erroneous and the Sun began to be considered the center of everything. But then it turned out that the star that gives life to all life on the blue planet is by no means the center of outer space, but only a tiny grain of sand in a boundless ocean of stars.

Space, galaxy, Milky way

The cosmos visible to the human eye includes myriads of stars. They all unite into a huge star system, which has a very beautiful and intriguing name - the Milky Way galaxy. From Earth, this celestial splendor is observed in the form of a wide whitish stripe, glowing dimly on the celestial sphere.

It stretches across the entire northern hemisphere and crosses the constellations Gemini, Auriga, Cassiopeia, Chanterelle, Cygnus, Taurus, Eagle, Sagittarius, Cepheus. Encircles Southern Hemisphere and passes through the constellation Monoceros, Southern Cross, Southern Triangle, Scorpio, Sagittarius, Sails, Compass.

If you arm yourself with a telescope and look through it at the night sky, the picture will be different. The wide whitish stripe will turn into countless luminous stars. Their faint, distant, alluring light will tell without words about the greatness and endless expanses of the Cosmos, will make you hold your breath and realize the insignificance and worthlessness of momentary human problems.

The Milky Way is called Galaxy or a giant star system. According to estimates, there is currently an increasing tendency towards a figure of 400 billion stars in the Milky Way. All these stars move in closed orbits. They are connected to each other by gravitational forces, and most of them have planets. Stars together with planets form star systems. Such systems come with one star ( solar system), double (Sirius - two stars), triple (Alpha Centauri). There are four, five stars, and even seven.

Milky Way in disk shape

Structure of the Milky Way

All this countless variety of star systems that make up the Milky Way is not scattered haphazardly throughout outer space, but is united into a colossal formation, shaped like a disk with a thickening in the middle. The diameter of the disk is 100,000 light years (one light year corresponds to the distance that light travels in a year, which is approximately 10¹³ km) or 30,659 parsecs (one parsec is 3.2616 light years). The thickness of the disk is several thousand light years, and its mass exceeds the mass of the Sun by 3 × 10¹² times.

The mass of the Milky Way consists of the mass of stars, interstellar gas, dust clouds and a halo, which has the shape of a huge sphere consisting of rarefied hot gas, stars and dark matter. Dark matter appears to be a collection of hypothetical cosmic objects, the masses of which make up 95% of the entire Universe. These mysterious objects are invisible and do not react in any way to modern technical means of detection.

The presence of dark matter can be guessed only by its gravitational effect on visible clusters of suns. There are not so many of them available for observation. The human eye, even enhanced by the most powerful telescope, can only contemplate two billion stars. Everything else outer space hidden by huge impenetrable clouds consisting of interstellar dust and gas.

Thickening ( bulge) in the central part of the Milky Way's disk is called the Galactic center or core. Billions of old stars move in it in very elongated orbits. Their mass is very large and is estimated at 10 billion solar masses. The core dimensions are not that impressive. It is 8000 parsecs across.

Galaxy Core- This is a brightly shining ball. If earthlings could observe it in the sky, then they would see a giant luminous ellipsoid, which in size would be a hundred times larger than the Moon. Unfortunately, this most beautiful and magnificent spectacle is inaccessible to people due to powerful gas and dust clouds that obscure the galactic center from planet Earth.

At a distance of 3000 parsecs from the center of the Galaxy there is a gas ring with a width of 1500 parsecs and a mass of 100 million solar masses. It is here that the central region of new star formation is believed to be located. Gas sleeves about 4 thousand parsecs long spread out from it. At the very center of the core there is black hole , with a mass of more than three million Suns.

Galactic disk its structure is heterogeneous. It has separate high-density zones, which are spiral arms. The continuous process of formation of new stars continues in them, and the arms themselves stretch along the core and seem to bend around it in a semicircle. Currently there are five of them. These are the Cygnus arm, the Perseus arm, the Centauri arm and the Sagittarius arm. In the fifth sleeve - Orion's arm- The solar system is located.

Please note - this is a spiral structure. Increasingly, people notice this structure literally everywhere. Many will be surprised, but flight path of our Earth Also there is a spiral!

It is separated from the galactic core by 28,000 light years. Around the center of the Galaxy, the Sun and its planets rush at a speed of 220 km/s, and complete a revolution in 220 million years. True, there is another figure - 250 million years.

The solar system is located just below the galactic equator, and in its orbit it does not move smoothly and calmly, but as if bouncing. Once every 33 million years, it crosses the galactic equator and rises above it to a distance of 230 light years. Then it descends back to repeat its takeoff after another interval of 33 million years.

The galactic disk rotates, but it does not rotate as a single body. The core rotates faster, the spiral arms in the plane of the disk rotate slower. Naturally, a logical question arises: why the spiral arms do not twist around the center of the Galaxy, but always remain the same shape and configuration for 12 billion years (the age of the Milky Way is estimated at this figure).

There is a certain theory that quite plausibly explains this phenomenon. She views spiral arms not as material objects, but as waves of matter density arising against the galactic background. This is caused by star formation and the birth of high luminosity stars. In other words, the rotation of the spiral arms has nothing to do with the movement of stars in their galactic orbits.

The latter, only, pass through the arms either ahead of them in speed if they are closer to the Galactic center, or behind them if they are located in the peripheral regions of the Milky Way. The outlines of these spiral waves are given by brightest stars which have very short life and manage to live it without leaving the sleeve.

As can be seen from all of the above, the Milky Way is a very complex cosmic formation, but it is not limited to the surface of the disk. There is a huge spherical cloud around ( halo). It consists of rarefied hot gases, individual stars, globular star clusters, dwarf galaxies and dark matter. On the outskirts of the Milky Way there are dense clouds of gas. Their extent is several thousand light years, their temperature reaches 10,000 degrees, and their mass is equal to at least ten million Suns.

Neighbors of the Milky Way Galaxy

In the vast Cosmos, the Milky Way is far from alone. At a distance of 772 thousand parsecs from it there is an even more huge star system. It's called Andromeda Galaxy(possibly more romantic - Andromeda Nebula). It has been known since ancient times as “a small celestial cloud, easily visible in dark night" Even at the beginning of the 17th century, religiously minded astronomers believed that “in this place the crystal firmament is thinner than usual, and through it the light of the kingdom of heaven pours out.”

The Andromeda Nebula is the only galaxy that can be seen in the sky naked eye. It appears as a small oval luminous spot. The light in it is unevenly distributed: the central part is brighter. If you strengthen your eye with a telescope, the speck will turn into a giant star system, the diameter of which is 150 thousand light years. This is one and a half times the diameter of the Milky Way.

Dangerous neighbor

But Andromeda is not unique in size from the galaxy in which the Solar System exists. Back in 1991, the planetary camera of the space telescope. Hubble recorded the presence of two nuclei. Moreover, one of them is smaller in size and revolves around another, larger and brighter one, gradually collapsing under the influence of the tidal forces of the latter. This slow death throes of one of the cores suggests that it is the remnant of some other galaxy that Andromeda absorbed.

For many, it will be an unpleasant surprise to learn that the Andromeda Nebula is moving towards the Milky Way, and, therefore, towards the Solar System. The approach speed is about 140 km/s. Accordingly, the meeting of the two stellar giants will take place somewhere in 2.5-3 billion years. This will not be a meeting on the Elbe, but it will not be a global catastrophe on a cosmic scale either..

Two Galaxies will simply merge into one. But which one will dominate - here the scales tip in favor of Andromeda. It has more mass, and it already has experience in absorbing other galactic systems.

As for the solar system, forecasts vary. The most pessimistic indicates that the Sun with all the planets will simply be thrown into intergalactic space, that is, there will be no place for it in the new formation.

But maybe this is for the better. After all, it is clear from everything that the Andromeda Galaxy is a kind of bloodthirsty monster, devouring its own kind. Having absorbed the Milky Way and destroyed its core, the Nebula will turn into a huge Nebula and continue its path across the expanses of the Universe, eating more and more new galaxies. The end result of this journey will be the collapse of an incredibly swollen, overly gigantic star system.

The Andromeda nebula will disintegrate into countless small stellar formations, exactly repeating the fate of the huge empires of human civilization, which first grew to unprecedented sizes, and then collapsed with a roar, unable to bear the burden of their own greed, self-interest and lust for power.

But you shouldn’t bother your head with the events of future tragedies. It is better to consider another galaxy, which is called Triangulum Galaxy. It is located in the vastness of the Universe at a distance of 730 thousand parsecs from the Milky Way and is two times smaller in size, and no less than seven times smaller in mass. That is, this is an ordinary mediocre galaxy, of which there are a great many in Space.

All these three star systems, along with several dozen more dwarf galaxies, are part of the so-called Local Group, which is part of Virgo Supercluster– a huge star formation, the size of which is 200 million light years.

The Milky Way, Andromeda Galaxy and the Triangulum Galaxy have a lot common features. All of them belong to the so-called spiral galaxies. Their disks are flat and consist of young stars, open star clusters and interstellar matter. In the center of each disc there is a thickening (bulge). The main feature, of course, is the presence of bright spiral arms containing many young and hot stars.

The cores of these galaxies are also similar in that they contain clusters of old stars and gas rings in which new stars are born. An invariable attribute of the central part of each nucleus is the presence of a black hole with a very large mass. It has already been mentioned that the mass of the Milky Way black hole corresponds to more than three million masses of the Suns.

Black holes- one of the most impenetrable mysteries of the Universe. Of course, they are observed and studied, but these mysterious formations are in no hurry to reveal their secrets. It is known that black holes have a very high density, and their gravitational field is so powerful that even light cannot escape from them.

But any cosmic body that finds itself in the zone of influence of one of them ( event threshold), will be immediately “swallowed” by this terrible universal monster. What will it be like further fate“unfortunate” is unknown. In short, it’s easy to get into a black hole, but impossible to get out of.

There are many black holes scattered across the expanses of space, some of them have a mass many times greater than the mass of the black hole at the center of the Milky Way. But this does not mean that the monster “native” to the Solar System is more harmless than its larger colleagues. It is also insatiable and bloodthirsty and is a compact (diameter equal to 12.5 light hours) and powerful source of X-ray radiation.

The name of this mysterious object Sagittarius A. Its mass has already been mentioned - more than 3 million solar masses, and the gravitational trap (event threshold) of the baby is measured at 68 astronomical units (1 AU is equal to the average distance of the Earth from the Sun). It is within these limits that lies the limit of his bloodthirstiness and treachery in relation to various cosmic bodies, which, for a number of reasons, frivolously cross it.

Someone probably naively thinks that the baby is content with random victims - nothing like that: he has a constant source of food. This is the star S2. It revolves around a black hole in a very compact orbit - a full revolution is only 15.6 years. Maximum distance S2 from scary monster lies within 5 daylight hours, and the minimum is only 17 daylight hours.

Under the influence of the tidal forces of a black hole, part of its substance is torn off from the star doomed to be slaughtered and flies at great speed towards this terrible cosmic monster. As it approaches, the substance turns into a state of hot plasma and, emitting a farewell bright glow, disappears forever into the insatiable invisible abyss.

But that’s not all: the insidiousness of a black hole has no limits. Next to it there is another, less massive and dense black hole. Its task is to adjust stars, planets, interstellar dust and gas clouds to its more powerful brother. All this also turns into plasma, emits bright light and disappears into nowhere.

However, not all scientists, despite such a demonstrative bloody interpretation of events, are of the opinion that black holes exist. Some argue that this is an unknown mass, driven under a cold, dense shell. It has enormous density and expands from the inside, squeezing it with incredible force. This kind of education is called gravastar– gravitational star.

They are trying to fit the entire Universe under this model, thus explaining its expansion. Proponents of this concept argue that outer space is a giant bubble, inflated by an unknown force. That is, the entire Cosmos is a huge gravastor, in which smaller models of gravastors coexist, periodically absorbing individual stars and other formations.

The absorbed bodies are, as it were, thrown into other outer spaces, which are essentially invisible, since they do not let out light from under an absolutely black shell. Maybe gravastors, these are other dimensions or parallel worlds? A specific answer to this question will not be found for a very, very long time.

But it’s not just the presence or absence of black holes that occupies the minds of space researchers. Much more interesting and exciting are thoughts about the existence of intelligent life in other star systems of the Universe.

The Sun, which gives life to earthlings, rotates among many other suns of the Milky Way. Its disk is visible from Earth as a pale shining strip encircling the celestial sphere. These are distant billions and billions of stars, many of which have their own planetary systems. Is there really not one among the countless number of these planets where intelligent beings live - brothers in mind?

The most reasonable assumption is that it is similar to earthly life can occur on a planet that orbits a star of the same class as the Sun. There is such a star in the sky, and besides, it is located in the star system closest to the earth’s body. This is Alpha Centauri A, located in the constellation Centaurus. From the earth it is visible to the naked eye, and its distance from the Sun is 4.36 light years.

It would be nice, of course, to have reasonable neighbors right next door. But what is desired does not always coincide with reality. Finding signs of an extraterrestrial civilization, even at a distance of some 4-6 light years, is a rather difficult task with current technological advances. Therefore, it is premature to talk about the existence of any intelligence in the constellation Centaurus.

Nowadays, it is only possible to send radio signals into space, hoping that someone unknown will answer the call of human intelligence. The most powerful radio stations in the world have been persistently and non-stop engaged in such activities since the first half of the 20th century. As a result, the level of radio emission from the Earth has increased significantly. The blue planet began to differ sharply in its radiation background from all other planets in the solar system.

Signals from Earth cover outer space with a radius of at least 90 light years. On the scale of the Universe, this is a drop in the ocean, but as you know, this little thing wears away the stone. If somewhere far, far away in Space there is highly developed intelligent life, then, in any case, it must someday turn its attention to both the increased background radiation in the depths of the Milky Way galaxy and the radio signals coming from there. Such an interesting phenomenon will not leave the inquisitive minds of aliens indifferent.

Accordingly adjusted and active search signals from space. But the dark abyss is silent, which indicates that within the Milky Way there are most likely no intelligent creatures ready to come into contact with the inhabitants of planet Earth, or their technical development is at a very primitive level. The truth suggests another thought, which suggests that a highly developed civilization, or civilizations, exists, but sends some other signals into the expanses of the Galaxy that cannot be picked up by earthly technical means.

Progress on the blue planet is steadily developing and improving. Scientists are developing new, completely different ways to transmit information over long distances. All this can have a positive effect. But we must not forget that the vastness of the Universe is limitless. There are stars, the light from which reaches the Earth after billions of years. In fact, a person sees a picture of the distant past when he observes such a cosmic object through a telescope.

It may happen that the signal received by earthlings from Space will turn out to be the voice of a long-vanished extraterrestrial civilization that lived at a time when neither the Solar System nor the Milky Way existed. The response message from Earth will reach the aliens, who were not even in the project at the time when it was sent.

Well, we must take into account the laws harsh reality. In any case, the search for intelligence in distant galactic worlds cannot be stopped. No luck to current generations, lucky for the future. Hope in this case will never die, and perseverance and perseverance will undoubtedly pay off handsomely.

But the exploration of galactic space seems quite realistic and close. Already in the next century, fast and graceful spaceships will fly to the nearest constellations. The astronauts on board will observe through their windows not the planet Earth, but the entire solar system. They will see her in the form of a distant, bright star. But this will not be the cold, soulless shine of one of the countless suns of the Galaxy, but the native radiance of the Sun, around which Mother Earth will revolve as an invisible, soul-warming speck of dust.

Very soon, the dreams of science fiction writers, reflected in their works, will become an ordinary everyday reality, and a walk along the Milky Way will become a rather boring and tedious activity, like, for example, a trip in a subway car from one end of Moscow to the other.

Milky Way (MP) is a huge gravitationally bound system containing at least 200 billion stars, thousands of giant clouds of gas and dust, clusters and nebulae. Belongs to the class of barred spiral galaxies. The MP is compressed in a plane and in profile looks like a “flying saucer”.

The Milky Way with the Andromeda Galaxy (M31), the Triangulum Galaxy (M33), and more than 40 dwarf satellite galaxies - its own and Andromeda - together form the Local Group of galaxies, which is part of the Local Supercluster (Virgo Supercluster).

Our Galaxy has the following structure: a core consisting of billions of stars, with a black hole in the center; a disk of stars, gas and dust with a diameter of 100,000 light years and a thickness of 1000 light years, in the middle part of the disk there is a bulge 3000 light years thick. years; sleeves; a spherical halo (corona) containing dwarf galaxies, globular star clusters, individual stars, groups of stars, dust and gas.

The central regions of the Galaxy are characterized by a strong concentration of stars: each cubic parsec near the center contains many thousands of them. The distances between stars are tens and hundreds of times smaller than in the vicinity of the Sun.

The galaxy rotates, but not uniformly across the entire disk. As you approach the center, the angular velocity of rotation of stars around the center of the Galaxy increases.

In the galactic plane, in addition to the increased concentration of stars, there is also an increased concentration of dust and gas. Between the center of the Galaxy and the spiral arms (branches) there is a gas ring - a mixture of gas and dust that emits strongly in the radio and infrared range. The width of this ring is about 6 thousand light years. It is located in an area between 10,000 and 16,000 light years from the center. The gas ring contains billions solar masses gas and dust and is a site of active star formation.

The Galaxy has a corona that contains globular clusters and dwarf galaxies (Large and Small Magellanic clouds and other clusters). The galactic corona also contains stars and groups of stars. Some of these groups interact with globular clusters and dwarf galaxies.

The plane of the Galaxy and the plane of the Solar system do not coincide, but are at an angle to each other, and the planetary system of the Sun rotates around the center of the Galaxy in approximately 180–220 million Earth years - this is how long one galactic year lasts for us.

In the vicinity of the Sun, it is possible to trace sections of two spiral arms that are approximately 3 thousand light years away from us. Based on the constellations where these areas are observed, they were given the name Sagittarius Arm and Perseus Arm. The sun is located almost in the middle between these spiral branches. But relatively close to us (by galactic standards), in the constellation Orion, there passes another, not very clearly defined arm - the Orion Arm, which is considered a branch of one of the main spiral arms of the Galaxy.

The speed of the Sun's rotation around the center of the Galaxy almost coincides with the speed of the compaction wave forming the spiral arm. This situation is atypical for the Galaxy as a whole: the spiral arms rotate at a constant angular velocity, like spokes in a wheel, and the movement of stars occurs according to a different pattern, so almost the entire stellar population of the disk either falls inside the spiral arms or falls out of them. The only place where the velocities of stars and spiral arms coincide is the so-called corotation circle, and it is on it that the Sun is located.

For the Earth, this circumstance is extremely important, since violent processes occur in the spiral arms, generating powerful radiation that is destructive for all living things. And no atmosphere could protect from it. But our planet exists in a relatively calm place in the Galaxy and has not been affected by these cosmic cataclysms for hundreds of millions (or even billions) of years. Perhaps this is why life was able to be born and survive on Earth.

An analysis of the Galaxy's rotation has shown that it contains large masses of non-luminous (non-emitting) matter, called "hidden mass" or "dark halo". The mass of the Galaxy, including this hidden mass, is estimated to be approximately 10 trillion solar masses. According to one hypothesis, part of the hidden mass may lie in brown dwarfs, in gas giant planets that occupy an intermediate position between stars and planets, and in dense and cold molecular clouds that have low temperature and are inaccessible for ordinary observations. In addition, in our and other galaxies there are many planet-sized bodies that are not included in any of the star systems and therefore are not visible through telescopes. Part of the hidden mass of galaxies may belong to “extinct” stars. According to another hypothesis, galactic space (vacuum) also contributes to the amount of dark matter. Hidden mass is not only in our Galaxy, it is in all galaxies.

The problem of dark matter in astrophysics arose when it became clear that the rotation of galaxies (including our own Milky Way) cannot be correctly described if we take into account only the ordinary visible (luminous) matter they contain. All the stars of the Galaxy in this case would have to fly apart and be scattered in the vastness of the Universe. In order for this not to happen (and this does not happen), the presence of additional invisible matter having a large mass is necessary. The action of this invisible mass manifests itself exclusively through gravitational interaction with visible matter. In this case, the amount of invisible matter should be approximately six times greater than the amount of visible matter (information about this was published in the scientific journal Astrophysical Journal Letters). The nature of dark matter, as well as dark energy, the presence of which is assumed in the observable Universe, remains unclear.

Divided into social groups, our Milky Way galaxy will belong to a strong “middle class”. Thus, it belongs to the most common type of galaxy, but at the same time it is not average in size or mass. Galaxies that are smaller than the Milky Way are larger than those that are larger than it. Our “star island” also has at least 14 satellites - other dwarf galaxies. They are doomed to circle around the Milky Way until they are absorbed by it, or fly away from an intergalactic collision. Well, for now this is the only place where life probably exists - that is, you and me.

But the Milky Way remains the most mysterious galaxy in the Universe: being on the very edge of the “star island”, we see only a part of its billions of stars. And the galaxy is completely invisible - it is covered with dense arms of stars, gas and dust. Today we will talk about the facts and secrets of the Milky Way.

The Milky Way Galaxy is very majestic and beautiful. This huge world– our Motherland, our Solar system. All the stars and other objects that are visible to the naked eye in the night sky are our galaxy. Although there are some objects that are located in the Andromeda Nebula, a neighbor of our Milky Way.

Description of the Milky Way

The Milky Way Galaxy is huge, 100 thousand light years in size, and, as you know, one light year is equal to 9460730472580 km. Our solar system is located 27,000 light years from the center of the galaxy, in one of the arms called the Orion arm.

Our solar system orbits the center of the Milky Way galaxy. This happens in the same way as the Earth rotates around the Sun. The solar system completes a full revolution in 200 million years.

Deformation

The Milky Way Galaxy appears as a disk with a bulge in the center. He doesn't perfect shape. On one side there is a bend north of the center of the galaxy, and on the other it goes down, then turns to the right. Outwardly, this deformation somewhat resembles a wave. The disk itself is deformed. This is due to the presence of the Small and Large Magellanic Clouds nearby. They rotate around the Milky Way very quickly - this was confirmed by the Hubble telescope. These two dwarf galaxies are often called satellites of the Milky Way. The clouds create a gravitationally bound system that is very heavy and quite massive due to the heavy elements in the mass. It is assumed that they seem to be in a tug-of-war between galaxies, creating vibrations. As a result, the Milky Way galaxy is deformed. The structure of our galaxy is special; it has a halo.

Scientists believe that in billions of years the Milky Way will absorb the Magellanic Clouds, and after some time it will be absorbed by Andromeda.

Halo

Wondering what kind of galaxy the Milky Way is, scientists began to study it. They managed to find out that 90% of its mass consists of dark matter, which is why a mysterious halo appears. Everything that is visible to the naked eye from Earth, namely that luminous matter, is approximately 10% of the galaxy.

Numerous studies have confirmed that the Milky Way has a halo. Scientists compiled various models, which took into account the invisible part and without it. After experiments, it was suggested that if there were no halo, then the speed of movement of the planets and other elements of the Milky Way would be less than now. Because of this feature, it was assumed that most of the components consist of invisible mass or dark matter.

Number of stars

The Milky Way galaxy is considered one of the most unique. The structure of our galaxy is unusual; there are more than 400 billion stars in it. About a quarter of them are large stars. Note: other galaxies have fewer stars. There are about ten billion stars in the Cloud, some others consist of a billion, and in the Milky Way there are more than 400 billion of the most different stars, and only a small part is visible from Earth, about 3000. It is impossible to say exactly how many stars are contained in the Milky Way, since the galaxy is constantly losing objects due to their transformation into supernovae.

Gases and dust

Approximately 15% of the galaxy is dust and gases. Maybe because of them our galaxy is called the Milky Way? Despite its enormous size, we can see about 6,000 light years ahead, but the size of the galaxy is 120,000 light years. It may be larger, but even the most powerful telescopes cannot see beyond that. This is due to the accumulation of gas and dust.

Thickness does not allow dust to pass through visible light, but infrared light passes through it, allowing scientists to create star maps.

What happened before

According to scientists, our galaxy has not always been like this. The Milky Way was created by the merger of several other galaxies. This giant captured other planets and areas, which had a strong impact on the size and shape. Even now, planets are being captured by the Milky Way galaxy. An example of this is objects Canis Major- a dwarf galaxy located near our Milky Way. Canis stars are periodically added to our universe, and from ours they move to other galaxies, for example, objects are exchanged with the Sagittarius galaxy.

View of the Milky Way

Not a single scientist or astronomer can say exactly what our Milky Way looks like from above. This is due to the fact that Earth is located in the Milky Way galaxy, 26,000 light years from the center. Because of this location, it is not possible to take pictures of the entire Milky Way. Therefore, any image of a galaxy is either pictures of other visible galaxies or someone’s imagination. And we can only guess what she really looks like. There is even a possibility that we now know as much about it as the ancient people who believed the Earth to be flat.

Center

The center of the Milky Way galaxy is called Sagittarius A* - a great source of radio waves, suggesting that there is a huge black hole at its very heart. According to assumptions, its size is a little more than 22 million kilometers, and this is the hole itself.

All the substances that try to get into the hole form a huge disk, almost 5 million times larger than our Sun. But even this retraction force does not prevent new stars from forming at the edge of the black hole.

Age

Based on estimates of the composition of the Milky Way galaxy, it was possible to establish an estimated age of about 14 billion years. The oldest star is just over 13 billion years old. The age of a galaxy is calculated by determining the age of the oldest star and the phases preceding its formation. Based on the available data, scientists have suggested that our universe is about 13.6-13.8 billion years old.

First, the bulge of the Milky Way was formed, then its middle part, in the place of which a black hole subsequently formed. Three billion years later, a disk with sleeves appeared. Gradually it changed, and only about ten billion years ago it began to look the way it does now.

We are part of something bigger

All the stars in the Milky Way galaxy are part of a larger galactic structure. We are part of the Virgo Supercluster. The closest galaxies to the Milky Way, such as the Magellanic Cloud, Andromeda and other fifty galaxies, are one cluster, the Virgo Supercluster. A supercluster is a group of galaxies that occupies a huge area. And this is only a small part of the stellar surroundings.

The Virgo Supercluster contains more than a hundred groups of clusters over an area more than 110 million light-years in diameter. The Virgo cluster itself is a small part of the Laniakea supercluster, and it, in turn, is part of the Pisces-Cetus complex.

Rotation

Our Earth moves around the Sun, making a full revolution in 1 year. Our Sun orbits in the Milky Way around the center of the galaxy. Our galaxy moves in relation to a special radiation. CMB radiation is a convenient reference point that allows us to determine the speed of a wide variety of matters in the Universe. Studies have shown that our galaxy rotates at a speed of 600 kilometers per second.

Appearance of the name

The galaxy got its name because of its special appearance, reminiscent of spilled milk in the night sky. The name was given to it back in Ancient Rome. Back then it was called the “milk road.” To this day it is called the Milky Way, associating the name with the appearance of a white stripe in the night sky, with spilled milk.

References to the galaxy have been found since the era of Aristotle, who said that the Milky Way is a place where celestial spheres contact with earthly ones. Until the telescope was created, no one added anything to this opinion. And only from the seventeenth century people began to look at the world differently.

Our neighbors

For some reason, many people think that the closest galaxy to the Milky Way is Andromeda. But this opinion is not entirely correct. Our closest “neighbor” is the Canis Major galaxy, located inside the Milky Way. It is located at a distance of 25,000 light years from us, and 42,000 light years from the center. In fact, we are closer to Canis Major than to the black hole at the center of the galaxy.

Before the discovery of Canis Major at a distance of 70 thousand light years, Sagittarius was considered the closest neighbor, and after that the Large Magellanic Cloud. Opened in Pse unusual stars with huge class M density.

According to the theory, the Milky Way swallowed Canis Major along with all its stars, planets and other objects.

Collision of galaxies

IN lately Information is increasingly being found that the closest galaxy to the Milky Way, the Andromeda Nebula, will swallow our universe. These two giants formed at about the same time - about 13.6 billion years ago. It is believed that these giants are capable of uniting galaxies, but due to the expansion of the Universe they should move away from each other. But, contrary to all the rules, these objects are moving towards each other. The speed of movement is 200 kilometers per second. It is estimated that in 2-3 billion years Andromeda will collide with Milky Way.

Astronomer J. Dubinsky created a model of the collision shown in this video:

The collision will not lead to a catastrophe on a global scale. And after several billion years it will form new system, with familiar galactic shapes.

Lost galaxies

Scientists conducted a large-scale study of the starry sky, covering approximately an eighth of it. As a result of the analysis of the star systems of the Milky Way galaxy, it was possible to find out that there are previously unknown streams of stars on the outskirts of our universe. This is all that remains of small galaxies that were once destroyed by gravity.

The telescope installed in Chile took a huge number of images that allowed scientists to assess the sky. The images estimate that our galaxy is surrounded by a halo of dark matter, thin gas and few stars, remnants of dwarf galaxies that were once swallowed up by the Milky Way. Having a sufficient amount of data, scientists were able to assemble a “skeleton” of dead galaxies. It’s like in paleontology - it’s difficult to say from a few bones what a creature looked like, but with enough data, you can assemble a skeleton and guess what the lizard was like. So it is here: the information content of the images made it possible to recreate eleven galaxies that were swallowed up by the Milky Way.

Scientists are confident that as they observe and evaluate the information they receive, they will be able to find several more new disintegrated galaxies that were “eaten” by the Milky Way.

We're under fire

According to scientists, the hypervelocity stars located in our galaxy did not originate in it, but in the Large Magellanic Cloud. Theorists cannot explain many aspects regarding the existence of such stars. For example, it is impossible to say exactly why it is concentrated large number hypervelocity stars in Sextant and Leo. Having revised the theory, scientists came to the conclusion that such a speed can only develop due to the influence of a black hole located in the center of the Milky Way.

Recently, more and more stars have been discovered that do not move from the center of our galaxy. After analyzing the trajectory of ultra-fast stars, scientists were able to find out that we are under attack by the Large Magellanic Cloud.

Death of the planet

By observing the planets in our galaxy, scientists were able to see how the planet died. She was consumed by the aging star. During the expansion and transformation into a red giant, the star absorbed its planet. And another planet in the same system changed its orbit. Having seen this and assessed the state of our Sun, scientists came to the conclusion that the same thing would happen to our luminary. In about five million years it will become a red giant.

How the galaxy works

Our Milky Way has several arms that rotate in a spiral. The center of the entire disk is a gigantic black hole.

We can see the galactic arms in the night sky. They look like white stripes, reminiscent of a milk road that is strewn with stars. These are the branches of the Milky Way. They are best seen in clear weather in the warm season, when there is the most cosmic dust and gases.

The following arms are distinguished in our galaxy:

1. Angle branch.
2. Orion. Our solar system is located in this arm. This sleeve is our “room” in the “house”.
3. Carina-Sagittarius sleeve.
4. Perseus branch.
5. Branch of the Shield of the Southern Cross.

It also contains a core, a gas ring, and dark matter. It supplies about 90% of the entire galaxy, and the remaining ten are visible objects.

Our Solar System, the Earth and other planets are a single whole of a huge gravitational system that can be seen every night in a clear sky. In our “home” a variety of processes are constantly taking place: stars are born, they decay, we are bombarded by other galaxies, dust and gases appear, stars change and go out, others flare up, they dance around... And all this happens somewhere out there, far away in a universe about which we know so little. Who knows, maybe the time will come when people will be able to reach other branches and planets of our galaxy in a matter of minutes, and travel to other universes.

> Milky Way

Milky Way– spiral galaxy with the solar system: interesting facts,size,area,detection and name,video study,structure,location.

The Milky Way is a spiral galaxy spanning an area of ​​100,000 light years in which the solar system is located.

If you have a place far from the city, where it is dark and open beautiful view looking at the starry sky, you may notice a faint light stripe. This is a group with millions of small bright lights and glowing halos. The stars are before you Milky Way galaxy.

But what is she? To begin with, the Milky Way is a barred spiral galaxy that is home to the Solar System. It is difficult to call the home galaxy something unique, because there are hundreds of billions of other galaxies in the Universe, many of which are similar.

Interesting facts about the Milky Way galaxy

• The Milky Way began to form as a cluster of dense regions after Big Bang. The first stars to appear were in globular clusters, which continue to exist. These are the oldest stars in the galaxy;
• The galaxy increased its parameters due to absorption and merger with others. It is now taking stars from the Sagittarius Dwarf Galaxy and the Magellanic Clouds;
• The Milky Way moves through space with an acceleration of 550 km/s relative to the cosmic microwave background radiation;
• The supermassive black hole Sagittarius A* lurks at the galactic center. Its mass is 4.3 million times greater than that of the Sun;
• Gas, dust and stars rotate around the center at a speed of 220 km/s. This is a stable indicator, implying the presence of a dark matter shell;
• In 5 billion years, a collision with the Andromeda Galaxy is expected. Some believe that the Milky Way is a giant spiral double system;

Discovering and naming the Milky Way galaxy

Our Milky Way galaxy has quite interesting name, as the foggy haze resembles a trail of milk. The name has ancient roots and is translated from the Latin “Via Lactea”. This name appears already in the work “Tadhira” by Nasir ad-Din Tusi. He wrote: “Represented by many small and densely grouped stars. They are located close together, so they appear like spots. The color resembles milk...” Admire a photo of the Milky Way galaxy with its arms and center (of course, no one can take a photo of our galaxy, but there are similar designs and precise structural data that provide an idea of ​​​​the appearance of the galactic center and arms).

Scientists thought that the Milky Way was filled with stars, but this remained only a guess until 1610. It was then that Galileo Galilei pointed the first telescope into the sky and saw individual stars. It also opened people up new truth: There are many more stars than we thought, and they are part of the Milky Way.

Immanuel Kant in 1755 believed that the Milky Way is a collection of stars united by a shared gravity. Gravitational force makes objects rotate and flattens them into a disk shape. In 1785, William Herschel tried to recreate the galactic shape, but did not realize that most of it was hidden behind a haze of dust and gas.

The situation changes in the 1920s. Edwin Hubble managed to convince us that we do not see spiral nebulae, but individual galaxies. It was then that the opportunity arose to realize our form. From that moment it became clear that this was a barred spiral galaxy. Watch the video to explore the structure of the Milky Way galaxy and explore its globular clusters and find out how many stars live in the galaxy.

Our galaxy: a view from the inside

Astrophysicist Anatoly Zasov about the main components of our galaxy, the interstellar medium and globular clusters:

Location of the Milky Way Galaxy

The Milky Way in the sky is quickly recognized thanks to its wide and elongated white line, reminiscent of a milky trail. Interestingly, this star group has been available for viewing since the formation of the planet. In fact, this area acts as the galactic center.

The galaxy extends 100,000 light years in diameter. If you were able to look at it from above, you would notice a bulge in the center, from which 4 large spiral arms emanate. This type represents 2/3 of the universe's galaxies.

Unlike the usual spiral, specimens with a jumper contain a rod in the center with two branches. Our galaxy has two main arms and two minor ones. Our system is located in the Orion Arm.

The Milky Way is not static and rotates in space, carrying all objects with it. The solar system moves around the galactic center at a speed of 828,000 km/h. But the galaxy is incredibly huge, so one passage takes 230 million years.

Spiral arms accumulate a lot of dust and gas, creating excellent conditions for the formation of new stars. The arms extend from the galactic disk, spanning approximately 1,000 light years.

At the center of the Milky Way you can see a bulge filled with dust, stars and gas. This is why you only get to see a small percentage of total number galactic stars. It's all about the thick gas and dust haze that blocks the view.

In the very center lies a supermassive black hole, billions of times more massive than the Sun. Most likely, it used to be much smaller, but a regular diet of dust and gas allowed it to grow. This is an incredible glutton, because sometimes even stars are sucked in. Of course, it is impossible to see it directly, but the gravitational influence is monitored.

Around the galaxy is a halo of hot gas, where old stars and globular clusters live. It extends over hundreds of thousands of light years, but contains only 2% of the stars that are in the disk. Let's not forget about dark matter(90% of galactic mass).

Structure and composition of the Milky Way galaxy

When observed, it is clear that the Milky Way divides the celestial space into two almost identical hemispheres. This suggests that our system is located near the galactic plane. It is noticeable that the galaxy has a low level of surface brightness due to the fact that gas and dust are concentrated in the disk. This not only makes it impossible to see the galactic center, but also to understand what is hiding on the other side. You can easily spot the center of the Milky Way galaxy in the diagram below.

If you managed to break out of the Milky Way and get a perspective from above, then you would see a spiral with a bar. It extends over 120,000 light years and is 1000 light years wide. For many years, scientists thought they saw 4 arms, but there are only two of them: Scutum-Centauri and Sagittarius.

The arms are created by dense waves rotating around the galaxy. They move around the area, so they compress dust and gas. This process starts active birth stars This happens in all galaxies of this type.

If you have come across photos of the Milky Way, then they are all artistic interpretations or other similar galaxies. It was difficult for us to comprehend its appearance, since we are located inside. Imagine that you want to describe the outside of a house if you have never left its walls. But you can always look out the window and look at the neighboring buildings. In the bottom picture you can easily understand where the Solar System is located in the Milky Way galaxy.

Ground and space missions have revealed that the galaxy is home to 100-400 billion stars. Each of them can have one planet, that is, the Milky Way galaxy is capable of housing hundreds of billions of planets, 17 billion of which are similar in size and mass to Earth.

Approximately 90% of the galactic mass goes to dark matter. No one can explain what we are facing. In principle, it has not yet been seen, but we know about its presence thanks to the rapid galactic rotation and other influences. It is this that keeps galaxies from being destroyed during rotation. Watch the video to learn more about the stars of the Milky Way.

Stellar population of the galaxy

Astronomer Alexey Rastorguev on the age of stars, star clusters and properties of the galactic disk:

Position of the Sun in the Milky Way Galaxy

Between the two main arms is the Orion Arm, in which our system is located 27,000 light-years from the center. There is no point in complaining about the remoteness, because a supermassive black hole (Sagittarius A*) lurks in the central part.

It takes our star, the Sun, 240 million years to orbit the galaxy (a cosmic year). This sounds incredible, because the last time the Sun was in this area, dinosaurs roamed the Earth. During its entire existence, the star made approximately 18-20 flybys. That is, it was born 18.4 space years ago, and the age of the galaxy is 61 space years.

Collision trajectory of the Milky Way galaxy

The Milky Way not only rotates, but also moves in the Universe itself. And although the space is large, no one is immune from collisions.

According to calculations, in about 4 billion years, our Milky Way galaxy will collide with the Andromeda galaxy. They are approaching at a speed of 112 km/s. After the collision, the process of star birth is activated. Overall, Andromeda is not the neatest racer, as it has crashed into other galaxies in the past (noticeably large dust ring in the center).

But earthlings should not worry about the future event. After all, by that time the Sun will already explode and destroy our planet.

What's next for the Milky Way galaxy?

It is believed that the Milky Way was created by the merger of smaller galaxies. This process continues, as the Andromeda Galaxy is already rushing towards us to create a giant ellipse in 3-4 billion years.

The Milky Way and Andromeda do not exist in isolation, but are part of the Local Group, which is also part of the Virgo Supercluster. This gigantic region (110 million light years) is home to 100 groups and galaxy clusters.

If you haven’t been able to admire your native galaxy, then do it as soon as possible. Find a quiet and dark place with an open sky and just enjoy this amazing star collection. Let us remind you that the site has a virtual 3D model of the Milky Way galaxy, which allows you to study all the stars, clusters, nebulae and famous planets online. And our star map will help you find all these celestial bodies in the sky on your own if you decide to buy a telescope.

Position and movement of the Milky Way