The Milky Way Galaxy is very majestic and beautiful. This huge world is 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 revolution every 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 are like 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 galaxy is considered one of the most unique Milky Way. 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 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, so how the galaxy is constantly losing objects due to them going supernova.

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.

The thickness of the dust does not allow visible light to pass through, but infrared light passes through, 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. Age itself old star– a little more than 13 billion years. 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.” It is still called that way - the Milky Way, associating the name specifically with appearance white streak on 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 the place where the celestial spheres contact the terrestrial 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. Unusual stars with enormous class M densities were discovered in Canis.

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

Collision of galaxies

Recently, information has become increasingly common 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, a new system will be formed, with the usual galactic forms.

Lost galaxies

Scientists conducted a large-scale study of the starry sky, covering approximately an eighth of it. As a result of an 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 a large number of hypervelocity stars are concentrated 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 from 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 cosmic dust and gases most of all.

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.

We are accustomed to the fact that the Milky Way is a cluster of stars in the sky along which our ancestors navigated. But in fact, this is more than ordinary night luminaries - this is a huge and unknown world.

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Structure of the Milky Way galaxy

Sometimes it seems incredible how dynamically space science is developing. It’s hard to imagine, but 4 centuries ago even the statement that the Earth revolves around the Sun caused condemnation and rejection in society. Judgments about these and others cosmic phenomena could lead not only to imprisonment, but also to death. Fortunately, times have changed, and the study of the Universe has long become a priority in science. Particularly important in this regard are studies of the Milky Way, a galaxy of thousands of stars, one of which is our Sun.

Studying the structure of the galaxy and its development helps answer the main questions that have interested humanity since the beginning of time. These are such sacramental mysteries about how the solar system arose, what factors contributed to the emergence of life on Earth, and whether life exists on other planets.

The fact that the Milky Way galaxy is a huge arm of an infinite star system became known relatively recently - a little more than half a century ago. The structure of our galaxy is similar to a colossal spiral, in which our solar system is located somewhere on the periphery. From the side, it looks like a giant magnifying glass with a bilaterally convex center with a crown.

What is the Milky Way galaxy? These are billions of stars and planets that are connected to each other by some algorithm for the structure of the Universe. In addition to stars, the Milky Way contains interstellar gas, galactic dust and star globular clusters.

The disk of our galaxy constantly rotates around the central part, which is located in the constellation Sagittarius. It takes 220 million years for the Milky Way to make one full revolution around its axis (and this despite the fact that rotation occurs at a speed of 250 kilometers per second). Thus, all the stars of our galaxy move in a single impulse for many years, and our Solar system along with them. What makes them rotate around the core at a truly frantic speed? Scientists suggest both the colossal weight of the center and the almost incomprehensible amount of energy (it may exceed the size of 150 million suns).

Why don’t we see any spirals or a giant core, why don’t we feel this universal rotation? The fact is that we are in the sleeve of this spiral Universe, and the frantic rhythm of its life is perceived by us in an everyday way.

Of course, there will be skeptics who will deny this structure of our galaxy, citing the fact that there is no accurate photograph of the galactic disk (and there cannot be one). The fact is that the Universe is by no means limited to the Milky Way galaxy and there are a lot of similar formations in space. They are very similar to our galaxy in structure - these are the same disks with a center around which stars revolve. That is, outside our Milky Way there are billions of systems similar to the Solar one.

The closest galaxy to us is the Large and Small Magellanic Clouds. They can be seen almost with the naked eye in the Southern Hemisphere. These two small luminous points, similar to clouds, were first described by great traveler, from whose name the names of space objects come. The diameter of the Magellanic Clouds is relatively small - less than half the Milky Way. And there are much fewer star systems in the Clouds.

Or the Andromeda Nebula. This is another spiral-shaped galaxy that is very similar in appearance and composition to the Milky Way. Its size is amazing - according to the most conservative estimates, it is three times larger than our Path. And the number of such gigantic galaxies in the Universe has long exceeded a billion - this is only what we can see at this stage in the development of astronomy. It is quite possible that in a few years we will become aware of another, previously unnoticed galaxy.

Characteristics of the Milky Way

As mentioned earlier, the Milky Way is a collection of millions of stars with their own systems, similar to the solar one. How many planets there are in our galaxy is a real mystery, which more than one generation of astronomers has been struggling to solve. Although, to be honest, they are more concerned about another question - what is the likelihood that within our galaxy there is a star system whose characteristics are similar to ours? Scientists are especially interested in stars that have a rotation speed similar to the Sun and technical specifications, as well as occupying our place on the galactic scale. This is because on planets similar in age and conditions to our Earth, there is a high probability of intelligent life.

Unfortunately, scientists’ attempts to find at least something similar to the solar system in the galaxy’s arms have not been successful. And this is probably for the best. It is still unknown who or what may await us in an unfamiliar constellation.

Is the Black Hole a planet killer or a galaxy creator?

At the end of its life, the star sheds its gas shell, and its core begins to shrink very quickly. Provided that the mass of the star is large enough (1.4 times more than the Sun), a Black Hole will form in its place. This is an object with a critical speed that no object can overcome. As a result, what falls into the Black Hole disappears into it forever. That is, in essence, this cosmic element is a one-way ticket. Any object that comes close enough to the Hole will disappear forever.

It's sad, isn't it? But there is also a positive aspect to the Black Hole - thanks to it, various cosmic objects are gradually pulled in and new galaxies are formed. It turns out that the core of each of the known star systems is a Black Hole.

Why is our galaxy called the Milky Way?

Each nation has its own legends about how the visible part of the Milky Way was formed. For example, the ancient Greeks believed that it was formed from the spilled milk of the goddess Hera. But in Mesopotamia there was a legend about a river made from the same drink. Thus, many peoples associated a large cluster of stars with milk, which is how our galaxy got its name.

How many stars are there in the Milky Way?

It is quite difficult to accurately calculate the number of stars in our galaxy, because they say that there are more than 200 billion of them. As you understand, studying them all with the modern development of science is very problematic, so scientists turn their attention only to the most interesting representatives of these space objects. Take, for example, the alpha star from the constellation Carina (Carina). This is a supergiant star, which for a long time held the title of the largest and brightest.

The Sun is also one of the stars in the Milky Way, which, however, does not have any outstanding characteristics. This is a small yellow dwarf, which has become famous only for being the source of life on our planet for millions of years.

Astronomers from all over the world have long compiled lists of stars that are distinguished by their outstanding mass or brightness. But this does not mean at all that each of them received given name. Typically, star names consist of letters, numbers and the names of the constellations to which they belong. Thus, the brightest star in the Milky Way is designated on astronomical maps as R136a1, and R136 is nothing more than the name of the nebula from which it comes. This star has indescribable power that cannot be compared with anything. R136a1 shines 8.7 million times brighter than our Sun, making it very difficult to imagine any life near it.

But colossal power does not mean that the R136a1 has impressive dimensions. The list of the largest stars is headed by UY Scuti, which is 1.7 thousand times larger than the size of our star. That is, if instead of the Sun there was this star, then it would occupy the entire space from the center of our system to Saturn.

Although no matter how large and powerful these stars are, their total mass cannot be compared with the mass of the Black Hole, which is located in the center of the galaxy. It is her colossal energy that holds the Milky Way, forcing it to move in a certain order.

Our galaxy is not just a scattering of stars in the night sky. This is a huge system that consists of hundreds of billions of stars, including our Sun.

Astronomers say that with the naked eye a person can see about 4.5 thousand stars. And this despite the fact that only a small part of one of the most amazing and unidentified pictures of the world is revealed to our eyes: in the Milky Way Galaxy alone there are more than two hundred billion celestial bodies (scientists have the opportunity to observe only two billion).

The Milky Way is a barred spiral galaxy, representing a huge gravitationally bound star system in space. Together with the neighboring Andromeda and Triangulum galaxies and more than forty dwarf satellite galaxies, it is part of the Virgo Supercluster.

The age of the Milky Way exceeds 13 billion years, and during this time from 200 to 400 billion stars and constellations, more than a thousand huge gas clouds, clusters and nebulae were formed in it. If you look at a map of the Universe, you can see that the Milky Way is presented on it in the form of a disk with a diameter of 30 thousand parsecs (1 parsec is equal to 3.086 * 10 to the 13th power of kilometers) and an average thickness of about a thousand light years (in one light year almost 10 trillion kilometers).

Astronomers find it difficult to answer exactly how much the Galaxy weighs, since most of the weight is not contained in the constellations, as previously thought, but in dark matter, which does not emit or interact with electromagnetic radiation. According to very rough calculations, the weight of the Galaxy ranges from 5*10 11 to 3*10 12 solar masses.

Like all celestial bodies, the Milky Way rotates around its axis and moves around the Universe. It should be taken into account that when moving, galaxies constantly collide with each other in space and the one that has larger sizes absorbs smaller ones, but if their sizes coincide, active star formation begins after the collision.

Thus, astronomers suggest that in 4 billion years the Milky Way in the Universe will collide with the Andromeda Galaxy (they are approaching each other at a speed of 112 km/s), causing the emergence of new constellations in the Universe.

As for the movement around its axis, the Milky Way moves unevenly and even chaotically in space, since each star system, cloud or nebula located in it has its own speed and orbits different types and forms.

Galaxy structure

If you look closely at a map of space, you can see that the Milky Way is very compressed in the plane and looks like a “flying saucer” (the Solar system is located almost at the very edge of the star system). The Milky Way Galaxy consists of a core, a bar, a disk, spiral arms and a crown.

Core

The core is located in the constellation Sagittarius, where there is a source of non-thermal radiation, the temperature of which is about ten million degrees - a phenomenon characteristic only of the nuclei of galaxies. In the center of the core there is a compaction - a bulge, consisting of large number old stars moving in an elongated orbit, many of which are at the end of their life cycle.

So, some time ago, American astronomers discovered an area here measuring 12 by 12 parsecs, consisting of dead and dying constellations.

At the very center of the core is a supermassive black hole(an area in outer space that has such powerful gravity that even light is unable to leave it), around which a smaller black hole rotates. Together they exert such a strong gravitational influence on nearby stars and constellations that they move along trajectories unusual for celestial bodies in the Universe.

Also, the center of the Milky Way is characterized by an extremely strong concentration of stars, the distance between which is several hundred times less than at the periphery. The speed of movement of most of them is absolutely independent of how far they are from the core, and therefore average speed rotation ranges from 210 to 250 km/s.

Jumper

The bridge, 27 thousand light years in size, crosses the central part of the Galaxy at an angle of 44 degrees to the conventional line between the Sun and the core of the Milky Way. It consists mainly of old red stars (about 22 million), and is surrounded by a gas ring that contains most of the molecular hydrogen, and is therefore a region where stars are formed in the greatest number. According to one theory, such active star formation occurs in the bridge due to the fact that it passes gas through itself, from which constellations are born.

Disk

The Milky Way is a disk consisting of constellations, gas nebulae and dust (its diameter is about 100 thousand light years with a thickness of several thousand). The disk rotates much faster than the corona, which is located at the edges of the Galaxy, while the rotation speed at different distances from the core is unequal and chaotic (varies from zero in the core to 250 km/h at a distance of 2 thousand light years from it). Gas clouds, as well as young stars and constellations, are concentrated near the plane of the disk.

WITH outside The Milky Way contains a layer of atomic hydrogen, which extends into space one and a half thousand light years from the outer spirals. Despite the fact that this hydrogen is ten times thicker than in the center of the Galaxy, its density is just as many times lower. On the outskirts of the Milky Way, dense accumulations of gas with a temperature of 10 thousand degrees, the dimensions of which exceed several thousand light years, were discovered.

Spiral sleeves

Immediately behind the gas ring there are five main spiral arms of the Galaxy, the size of which ranges from 3 to 4.5 thousand parsecs: Cygnus, Perseus, Orion, Sagittarius and Centauri (the Sun is located from inside Orion's arms). Molecular gas is located unevenly in the arms and does not always obey the rules of rotation of the Galaxy, introducing errors.

Crown

The Milky Way's corona appears as a spherical halo that extends five to ten light years beyond the Galaxy. The corona consists of globular clusters, constellations, individual stars (mostly old and low-mass), dwarf galaxies, and hot gas. They all move around the core in elongated orbits, and the rotation of some stars is so random that even the speed of nearby stars can differ significantly, so the corona rotates extremely slowly.

According to one hypothesis, the corona arose as a result of the absorption of smaller galaxies by the Milky Way, and therefore is their remnants. According to preliminary data, the age of the halo exceeds twelve billion years and is the same age as the Milky Way, and therefore star formation here has already completed.

star space

If you look at the night starry sky, the Milky Way can be seen from absolutely anywhere on the globe in the form of a strip of lightish color (since our star system is located inside the Orion arm, only part of the Galaxy is accessible for viewing).

The map of the Milky Way shows that our Sun is located almost on the disk of the Galaxy, at its very edge, and its distance to the core is from 26-28 thousand light years. Considering that the Sun moves at a speed of about 240 km/h, to make one revolution, it needs to spend about 200 million years (over the entire period of its existence, our star has not flown around the Galaxy thirty times).

It is interesting that our planet is located in a corotation circle - a place where the speed of rotation of stars coincides with the speed of rotation of the arms, so stars never leave these arms or enter them. This circle is characterized by high level radiation, therefore it is believed that life can only arise on planets near which there are very few stars.

This fact also applies to our Earth. Being on the periphery, it is located in a fairly quiet place in the Galaxy, and therefore for several billion years it was almost not subjected to global disasters, which the Universe is so rich in. Perhaps this is one of the main reasons that life was able to originate and survive on our planet.

The cosmos that we are trying to study is a huge and endless space in which there are tens, hundreds, thousands of trillions of stars, united in certain groups. Our Earth does not live on its own. We are part of solar system, which is a small particle and is part of the Milky Way, a larger cosmic formation.

Our Earth, like the other planets of the Milky Way, our star called the Sun, like other stars of the Milky Way, move in the Universe in a certain order and occupy designated places. Let's try to understand in more detail what is the structure of the Milky Way, and what are the main features of our galaxy?

Origin of the Milky Way

Our galaxy has its own history, like other areas of outer space, and is the product of a catastrophe on a universal scale. The main theory of the origin of the Universe that dominates the scientific community today is the Big Bang. A model that perfectly characterizes the Big Bang theory is the chain model. nuclear reaction at the microscopic level. Initially, there was some kind of substance that, for certain reasons, instantly began to move and exploded. There is no need to talk about the conditions that led to the onset of the explosive reaction. This is far from our understanding. Now the Universe, formed 15 billion years ago as a result of a cataclysm, is a huge, endless polygon.

The primary products of the explosion initially consisted of accumulations and clouds of gas. Subsequently, under the influence of gravitational forces and other physical processes, the formation of larger objects on a universal scale occurred. Everything happened very quickly by cosmic standards, over billions of years. First there was the formation of stars, which formed clusters and later merged into galaxies, the exact number of which is unknown. In terms of its composition, galactic matter is atoms of hydrogen and helium in the company of other elements, which are building material for the formation of stars and other space objects.

It is not possible to say exactly where in the Universe the Milky Way is located, since the exact center of the universe is unknown.

Due to the similarity of the processes that formed the Universe, our galaxy is very similar in structure to many others. By its type, it is a typical spiral galaxy, a type of object that is widespread in the Universe in great numbers. In terms of size, the galaxy is in the golden mean - neither small nor huge. Our galaxy has many more smaller stellar neighbors than those of colossal size.

The age of all galaxies that exist in outer space is also the same. Our galaxy is almost the same age as the Universe and is 14.5 billion years old. Over this enormous period of time, the structure of the Milky Way has changed several times, and this is still happening today, only imperceptibly, in comparison with the pace of earthly life.

There is a curious story about the name of our galaxy. Scientists believe that the name Milky Way is legendary. This is an attempt to connect the location of stars in our sky with ancient Greek myth about the father of the gods Kronos, who devoured his own children. The last child, who faced the same sad fate, turned out to be thin and was given to a nurse to be fattened. During feeding, splashes of milk fell on the sky, thereby creating a milk trail. Subsequently, scientists and astronomers of all times and peoples agreed that our galaxy is indeed very similar to a milk road.

The Milky Way is currently in the middle of its development cycle. In other words, the cosmic gas and material to form new stars is running out. The existing stars are still quite young. As in the story with the Sun, which may turn into a Red Giant in 6-7 billion years, our descendants will observe the transformation of other stars and the entire galaxy as a whole into the red sequence.

Our galaxy may cease to exist as a result of another universal cataclysm. Research topics recent years are guided by the upcoming meeting of the Milky Way with our closest neighbor, the Andromeda galaxy, in the distant future. It is likely that the Milky Way will break up into several small galaxies after meeting the Andromeda Galaxy. In any case, this will be the reason for the emergence of new stars and the reorganization of the space closest to us. We can only guess what the fate of the Universe and our galaxy will be in the distant future.

Astrophysical parameters of the Milky Way

In order to imagine what the Milky Way looks like on a cosmic scale, it is enough to look at the Universe itself and compare its individual parts. Our galaxy is part of a subgroup, which in turn is part of the Local Group, a larger formation. Here our cosmic metropolis neighbors the Andromeda and Triangulum galaxies. The trio is surrounded by more than 40 small galaxies. The local group is already part of an even larger formation and is part of the Virgo supercluster. Some argue that these are only rough guesses about where our galaxy is located. The scale of the formations is so enormous that it is almost impossible to imagine it all. Today we know the distance to the nearest neighboring galaxies. Other deep space objects are out of sight. Their existence is only theoretically and mathematically allowed.

The location of the galaxy became known only thanks to approximate calculations that determined the distance to its nearest neighbors. The Milky Way's satellites are dwarf galaxies - the Small and Large Magellanic Clouds. In total, according to scientists, there are up to 14 satellite galaxies that form the escort of the universal chariot called the Milky Way.

As for the visible world, today there is enough information about what our galaxy looks like. The existing model, and with it the map of the Milky Way, is compiled on the basis of mathematical calculations, data obtained as a result of astrophysical observations. Each cosmic body or fragment of the galaxy takes its place. It’s like in the Universe, only on a smaller scale. The astrophysical parameters of our cosmic metropolis are interesting, and they are impressive.

Our galaxy is a barred spiral galaxy, which is designated on star maps by the index SBbc. The diameter of the galactic disk of the Milky Way is about 50-90 thousand light years or 30 thousand parsecs. For comparison, the radius of the Andromeda galaxy is 110 thousand light years on the scale of the Universe. One can only imagine how much larger our neighbor is than the Milky Way. The sizes of the dwarf galaxies closest to the Milky Way are tens of times fewer parameters of our galaxy. Magellanic clouds have a diameter of only 7-10 thousand light years. There are about 200-400 billion stars in this huge stellar cycle. These stars are collected in clusters and nebulae. A significant part of it is the arms of the Milky Way, in one of which our solar system is located.

Everything else is dark matter, clouds of cosmic gas and bubbles that fill interstellar space. The closer to the center of the galaxy, the more stars, the tighter it gets outer space. Our Sun is located in a region of space consisting of smaller space objects located at a considerable distance from each other.

The mass of the Milky Way is 6x1042 kg, which is trillions of times more than the mass of our Sun. Almost all the stars inhabiting our stellar country are located in the plane of one disk, the thickness of which, according to various estimates, is 1000 light years. It is not possible to know the exact mass of our galaxy, since most of the visible spectrum of stars is hidden from us by the arms of the Milky Way. In addition, the mass of dark matter, which occupies vast interstellar spaces, is unknown.

The distance from the Sun to the center of our galaxy is 27 thousand light years. Being on the relative periphery, the Sun rapidly moves around the center of the galaxy, completing a full revolution every 240 million years.

The center of the galaxy has a diameter of 1000 parsecs and consists of a core with an interesting sequence. The center of the core has the shape of a bulge, in which the largest stars and a cluster of hot gases are concentrated. It is this region that releases a huge amount of energy, which in total is greater than that emitted by the billions of stars that make up the galaxy. This part of the core is the most active and brightest part of the galaxy. At the edges of the core there is a bridge, which is the beginning of the arms of our galaxy. Such a bridge arises as a result of the colossal gravitational force caused by the rapid speed of rotation of the galaxy itself.

Considering the central part of the galaxy, the following fact appears paradoxical. Scientists for a long time could not understand what is in the center of the Milky Way. It turns out that in the very center of a starry country called the Milky Way there is a supermassive black hole, the diameter of which is about 140 km. It is there that most of the energy released by the galactic core goes; it is in this bottomless abyss that stars dissolve and die. The presence of a black hole at the center of the Milky Way indicates that all processes of formation in the Universe must end someday. Matter will turn into antimatter and everything will happen again. How this monster will behave in millions and billions of years, the black abyss is silent, which indicates that the processes of absorption of matter are only gaining strength.

The two main arms of the galaxy extend from the center - the Shield of the Centaur and the Shield of Perseus. These structural formations received their names from the constellations located in the sky. In addition to the main arms, the galaxy is surrounded by 5 more minor arms.

Near and distant future

The arms, born from the core of the Milky Way, unwind in a spiral, filling outer space with stars and cosmic material. An analogy with cosmic bodies that revolve around the Sun in our star system is appropriate here. A huge mass of stars, large and small, clusters and nebulae, cosmic objects of various sizes and natures, spins on a giant carousel. All of them create a wonderful picture of the starry sky, which people have been looking at for thousands of years. When studying our galaxy, you should know that the stars in the galaxy live according to their own laws, being today in one of the arms of the galaxy, tomorrow they will begin their journey in the other direction, leaving one arm and flying to another.

Earth in the Milky Way galaxy is far from the only planet suitable for life. This is just a particle of dust, the size of an atom, which is lost in the vast star world of our galaxy. There can be a huge number of such Earth-like planets in the galaxy. It is enough to imagine the number of stars that in one way or another have their own stellar planetary systems. Other life may be far away, at the very edge of the galaxy, tens of thousands of light years away, or, conversely, present in neighboring areas that are hidden from us by the arms of the Milky Way.

MILKY WAY
a hazy glow in the night sky from the billions of stars in our Galaxy. The Milky Way band encircles the sky in a wide ring. The Milky Way is especially visible away from city lights. In the Northern Hemisphere, it is convenient to observe it around midnight in July, at 10 pm in August or at 8 pm in September, when the Northern Cross of the Cygnus constellation is near the zenith. As we follow the Milky Way's shimmering streak north or northeast, we pass the W-shaped constellation Cassiopeia and head toward the bright star Capella. Beyond the Chapel, you can see how the less wide and bright part of the Milky Way passes just east of Orion's Belt and leans towards the horizon not far from Sirius, the brightest star in the sky. The brightest part of the Milky Way is visible in the south or southwest at times when the Northern Cross is overhead. At the same time, two branches of the Milky Way are visible, separated by a dark gap. The Scutum Cloud, which E. Barnard called the “pearl of the Milky Way,” is located halfway to the zenith, and below are the magnificent constellations Sagittarius and Scorpio.

Unfortunately, the brightest parts of the Milky Way are inaccessible to observers in the Northern Hemisphere. To see them, you need to go to the equator, or even better, position yourself between 20 and 40° S. and watch the sky approx. 10 pm in late April or early May. High in the sky is the Southern Cross, and low in the northwest is Sirius. The faint and narrow Milky Way runs between them, but it becomes much brighter and more interesting 30° west of the Southern Cross, in the constellation Carina. As Sagittarius and Scorpio rise in the east, the brightest and most magnificent parts of the Milky Way appear. Its most remarkable area is visible late in the evening in June-July, when the Sagittarius Cloud is located near the zenith. Against the background of a uniform glow caused by thousands and thousands of distant stars invisible to the eye, one can notice dark clouds and “veins” of cold cosmic dust. Anyone who wants to understand the structure of our Galaxy should take the time to observe the Milky Way - this truly remarkable and most grandiose of celestial phenomena.

To discern the myriad stars that make up the Milky Way, all you need is binoculars or a small telescope. The greatest concentration of stars and the maximum width of the Milky Way are observed in the constellations Sagittarius and Scorpio; it is the least populated by stars opposite side sky - near Orion's Belt and Capella. Accurate astronomical observations confirm the first visual impression: the band of the Milky Way marks the central plane of a giant disk-shaped star system - our Galaxy, often called the "Milky Way Galaxy". One of its stars is our Sun, located very close to the central plane of the Galaxy. However, the Sun is not at the center of the galactic disk, but at a distance of two-thirds from its center to the edge. The stars that make up the Milky Way are located at different distances from the Earth: some are no further than 100 light years. years, and most are removed by 10,000 sv. years and even further. The star cloud in Sagittarius and Scorpio marks the direction of the center of the Galaxy, located at a distance of approximately 30,000 light years from Earth. years. The diameter of the entire Galaxy is at least 100,000 St. years.
Composition of the Milky Way. The galaxy consists mainly of stars, more or less similar to the Sun. Some of them are several times more massive than the Sun and glow several thousand times brighter, others are several times less massive and glow several thousand times weaker. The Sun is, in many ways, an average star. Depending on the surface temperature, stars have different colors: blue-white stars are the hottest (20,000-40,000 K), and red stars are the coolest (approx. 2500 K). Some stars form groups called star clusters. Some of them are visible to the naked eye, such as the Pleiades. This is a typical open cluster; Typically such clusters contain from 50 to 2000 stars. In addition to open clusters, there are much larger globular clusters containing up to several million stars. These clusters vary significantly in age and stellar composition. Open clusters are relatively young: their typical age is ca. 10 million years, i.e. OK. 1/500th the age of the Earth and the Sun. They contain many massive bright stars. Globular clusters are very old: 10-15 billion years have passed since their formation, i.e. they consist of the oldest stars in the Galaxy, among which only low-mass ones have survived. Open clusters are located near the galactic plane, where there is a lot of interstellar gas from which stars form. Globular clusters fill the galactic halo surrounding the disk and are noticeably concentrated towards the center of the Galaxy.
See also
GALAXIES;
STARS ;
CONSTELLATION. The mass of the Galaxy is at least 2*10 11 solar masses. These are mostly stars, but 5% of its mass is interstellar matter - gas and dust. Interstellar matter fills the space between stars in the galactic disk with a thickness of approx. 600 St. years, and inside the disk it concentrates towards the spiral arms of the Galaxy. A significant part of the interstellar matter is combined into massive cold clouds, in the depths of which stars form.
See also INTERSTELLAR MATTER. The Milky Way Galaxy is one of hundreds of millions of similar star systems discovered in the Universe using large telescopes. She is often called "our star system". It belongs to large galaxies that have rapid rotation and clear spiral arms, in which young hot stars and clouds of gas heated by their radiation, called “emission nebulae,” are concentrated. Using optical telescopes, it is not possible to study the entire Galaxy, since light does not penetrate through dense interstellar clouds of gas and dust, which are especially numerous towards the center of the Galaxy. However, dust is not a hindrance for infrared radiation and radio emission: with the help of appropriate telescopes it is possible to explore the entire Galaxy and even get to its dense core. Observations have shown that stars and gas are in. The galactic disk moves at a speed of about 250 km/s around the center of the Galaxy. Our Sun, together with the planets, also moves at the same speed, making one revolution around the galactic center in about 200 million years.

Collier's Encyclopedia. - Open Society. 2000 .

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See what "MILKY WAY" is in other dictionaries:

Milky Way Galaxy ( computer model). Barred spiral galaxy. Two of the four branches dominate. Characteristics Type SBbc (spiral galaxy with bar) Diameter ... Wikipedia

MILKY WAY, a faint band of light visible in the sky on clear, dark nights, running along the line of the galactic equator. It is formed as a result of the glow of a huge number of stars, in some areas covered by clouds of interstellar gas and... ... Scientific and technical encyclopedic dictionary

A wide strip in the sky consisting of countless stars. Wed. The whole sky is strewn with cheerfully twinkling stars, and the Milky Way appears as clearly as if it had been washed and covered with snow before the holiday. A.P. Chekhov. Vanka. See Moiseeva... ... Michelson's Large Explanatory and Phraseological Dictionary (original spelling)

MILKY WAY, 1) a dimly luminous stripe crossing the starry sky. It is a huge number of visually indistinguishable stars, concentrating towards the main plane of the Galaxy. The Sun is located near this plane, so... ... Modern encyclopedia

1) a dimly luminous stripe crossing the starry sky. It is a huge number of visually indistinguishable stars, concentrating towards the main plane of the Galaxy. The Sun is located near this plane, so most stars... ... Big Encyclopedic Dictionary

MILKY, oh, oh Dictionary Ozhegova. S.I. Ozhegov, N.Yu. Shvedova. 1949 1992 … Ozhegov's Explanatory Dictionary

1) Galaxy. 2) A light stripe in the night sky is a projection onto the celestial sphere of distant (from the Sun) stars of the Galaxy, close to its plane. Increase The brightness of this band is due to higher concentration of stars in the galactic plane. Physical... ... Physical encyclopedia