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Names of stars in the Milky Way. The history of the discovery of the Milky Way Galaxy. Galactic structure and its influence on the number of stars

Planet Earth, solar system , and all the stars visible naked eye are situated in Galaxy Milky Way , which is a barred spiral galaxy that has two distinct arms starting at the ends of the bar.

This was confirmed in 2005 by the Lyman Spitzer Space Telescope, which showed that the central bar of our galaxy is larger than previously thought. Spiral galaxies with a bar - spiral galaxies with a bar (“bar”) of bright stars, emerging from the center and crossing the galaxy in the middle.

The spiral arms in such galaxies begin at the ends of the bars, whereas in ordinary spiral galaxies they extend directly from the core. Observations show that about two-thirds of all spiral galaxies are barred. According to existing hypotheses, bridges are centers of star formation that support the birth of stars in their centers. It is assumed that, through orbital resonance, they allow gas from the spiral arms to pass through them. This mechanism provides the influx of building material for the birth of new stars.

The Milky Way, together with the Andromeda galaxy (M31), Triangulum galaxy (M33), and more than 40 smaller satellite galaxies form the Local Group of Galaxies, which, in turn, is part of the Virgo Supercluster. "Using infrared imaging from NASA's Spitzer Telescope, scientists have discovered that the Milky Way's elegant spiral structure has only two dominant arms from the ends of a central bar of stars. Previously, our galaxy was thought to have four main arms." /s.dreamwidth.org/img/styles/nouveauoleanders/titles_background.png" target="_blank">http://s.dreamwidth.org/img/styles/nouveauoleanders/titles_background.png) 0% 50% no-repeat rgb(29, 41, 29);">
In appearance, the galaxy resembles a disk (since the bulk of the stars are located in the form of a flat disk) with a diameter of about 30,000 parsecs (100,000 light years, 1 quintillion kilometers) with an estimated average thickness of the disk of the order of 1000 light years, the diameter of the bulge is The center of the disk is 30,000 light years away. The disk is immersed in a spherical halo, and around it is a spherical corona. The center of the galactic core is located in the constellation Sagittarius. The thickness of the galactic disk at the location where it is located solar system with planet Earth is 700 light years. The distance from the Sun to the center of the Galaxy is 8.5 kiloparsecs (2.62.1017 km, or 27,700 light years). solar system located on the inner edge of an arm called the Orion Arm. In the center of the Galaxy, apparently, there is a supermassive black hole(Sagittarius A*) (about 4.3 million solar masses) around which, presumably, revolves a black hole of average mass from 1000 to 10,000 solar masses and an orbital period of about 100 years and several thousand relatively small ones. The galaxy contains, according to the lowest estimate, about 200 billion stars ( modern assessment ranges from 200 to 400 billion). As of January 2009, the mass of the Galaxy is estimated at 3.1012 solar masses, or 6.1042 kg. The bulk of the Galaxy is contained not in stars and interstellar gas, but in a non-luminous halo of dark matter.

Compared to the halo, the Galaxy's disk rotates noticeably faster. Its rotation speed is not the same different distances from the center. It rapidly increases from zero at the center to 200-240 km/s at a distance of 2 thousand light years from it, then decreases somewhat, increases again to approximately the same value and then remains almost constant. Studying the peculiarities of the rotation of the Galaxy's disk made it possible to estimate its mass; it turned out that it is 150 billion times greater than the mass of the Sun. Age Milky Way galaxies equals13,200 million years old, almost as old as the Universe. The Milky Way is part of the Local Group of galaxies.

/s.dreamwidth.org/img/styles/nouveauoleanders/titles_background.png" target="_blank">http://s.dreamwidth.org/img/styles/nouveauoleanders/titles_background.png) 0% 50% no-repeat rgb(29, 41, 29);">Location of the Solar System solar system is located on the inner edge of an arm called the Orion Arm, in the outskirts of the Local Supercluster, which is sometimes also called the Virgo Super Cluster. The thickness of the galactic disk (in the place where it is located) solar system with planet Earth) is 700 light years. The distance from the Sun to the center of the Galaxy is 8.5 kiloparsecs (2.62.1017 km, or 27,700 light years). The sun is located closer to the edge of the disk than to its center.

Together with other stars, the Sun rotates around the center of the Galaxy at a speed of 220-240 km/s, making one revolution in approximately 225-250 million years (which is one galactic year). Thus, during its entire existence, the Earth has flown around the center of the Galaxy no more than 30 times. The galactic year of the Galaxy is 50 million years, the period of revolution of the jumper is 15-18 million years. 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. A diagram of the location of the Earth in the Universe in a series of eight maps that show, from left to right, starting with the Earth, moving in solar system, to neighboring star systems, to the Milky Way, to local Galactic groups, tolocal Virgo superclusters, on our local supercluster, and ends in the observable Universe.



Solar System: 0.001 light years

Neighbors in interstellar space



Milky Way: 100,000 light years

Local Galactic Groups



Local Virgo Supercluster



Local above a cluster of galaxies



Observable Universe

> 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 further away from the city, where it is dark and has a beautiful view of the starry sky, you may notice a faint streak of light. 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 forming as a cluster of dense regions after the 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 a rather interesting name, as the hazy 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 the Milky Way was filled with stars, but this remained a guess until 1610. It was then that Galileo Galilei pointed the first telescope into the sky and saw individual stars. It also revealed a new truth to people: 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. I wonder what this star group available for review 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 the total number of stars in the galaxy. 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 the 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 1000 light years in width. 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 triggers the active birth of 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 understand it 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.

It is estimated that 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 known planets online. And our star map will help you find all these celestial bodies in the sky yourself if you decide to buy a telescope.

Position and movement of the Milky Way

Everyone has ever thought about how large and unknown the world around us is. Being a part is immeasurable vast universe, we often and curiously ask ourselves questions: “How big is the Universe?”, “What does it consist of?”, “Is there intelligent life besides us?”, “How many galaxies are there in the Universe?” and many others.

This article seeks to answer some of them and expand on general knowledge and ideas about the Universe and its constituent parts and systems.

Universe

The universe includes everything that exists. From cosmic dust to giant stars; from the smallest hydrogen atoms to subjective ideas and abstract concepts. Everything that is located and functions in space is part of the Universe.

She is being studied various sciences. Physics, astronomy and cosmology are pioneers in the study of the Universe in objective reality. They are the ones who are trying to answer the question of what the cosmos is made of or how many galaxies there are in the Universe. From its very first days, philosophy has been studying the Universe in subjective reality. The mother of all sciences is not concerned about how many galaxies there are in the Universe, but about how it and its perception affect our life and development.

Given the incredible size of the Universe and the mass of bodies and substances found in it, it is not surprising that we have accumulated a huge amount of knowledge; it is also not surprising that much large quantity questions remain unanswered. Only a small part of the Universe can be physically studied at a certain point in time; we can only guess about the rest. The past and future of the Universe are only assumptions and predictions, and its present is revealed to us only to a tiny extent.

What do we know for sure about her?

We are absolutely sure that the Universe is huge, and with a high degree of probability we can say that it is immeasurable. To measure distances between cosmic objects, a completely “universal” unit is used - the light year. This is the distance that a beam of light can travel in a year.

The matter that makes up the Universe surrounds our planet at a distance of at least 93 billion light years. For comparison, our galaxy occupies a place that can be covered in 100 thousand light years.

Scientists divide cosmic matter into a cluster of atoms - understandable and studied physical matter, which is also called baryonic matter. However, most of the Universe is occupied by unexplored dark energy, the properties of which are unknown to scientists. Also, a considerable part of the visible space of the Universe is occupied by dark or hidden mass, which scientists call invisible matter.

The accumulation of baryonic matter forms stars, planets and other cosmic bodies, which, in turn, form galaxies. The latter are in motion and moving away from each other. It is impossible to answer the question of how many galaxies there are in the Universe with precision.

What can we only guess?

The past of the Universe and the process of its formation are precisely unknown. Scientists suggest that the Universe is almost 14 billion years old and formed after the expansion of concentrated hot matter, which in cosmology is called the Big Bang Theory.

Scientists obtain everything on which the main theoretical models of the evolution of the Universe are based by observing the part of it visible to us. It is impossible to prove how true any of the currently existing models is. Most scientists agree with the theory of the expansion of the Universe - after the “big bang”, cosmic matter continues its movement from its center.

It is worth remembering that all these models are theoretical, and it is impossible to test them in practice for many reasons. Therefore, it is worth concentrating on accessible and proven knowledge that answers the questions about how many stars are in the galaxy, and how many galaxies are in the Universe. Photo taken with modern technologies, called Hubble (for Hubble Ultra Deep Field), allows you to see the location of many galaxies in a small visible part of the sky.

What is a galaxy?

A galaxy is a collection of stars, gas, dust and hidden mass. Gravitational interaction baryonic matter and dark cosmic mass unites the galaxy into a tightly connected group of cosmic bodies. Galaxies move at a certain speed, which confirms the theory of the expansion of the Universe, but the gravitational center of the galaxy does not allow the movement of the Universe to influence its formation. All bodies in the galaxy revolve around a gravitational center.

Galaxies may be various types, sizes and consist of many systems. There is no single answer to the question of how many galaxies there are in the Universe, since the existence of two identical galaxies is unlikely. By type they are divided into:

  • elliptical;
  • spiral;
  • lenticular;
  • with jumper;
  • incorrect.

Based on their size, galaxies are classified as dwarf, medium, large and giant. There is no clear answer to the question of how many systems there are in a galaxy, since the number of systems and star clusters depends on many different factors, such as the gravitational field of the stars, the size of the galaxy, and many others.

Scale of galaxies

Each galaxy consists of star systems, clusters and interstellar clouds. Several neighboring galaxies can be attracted to each other and form a local group. It can contain from three to 30 galaxies of various types and sizes.

Clusters of local groups, in turn, form huge clouds of stars called superclusters of galaxies. The gravitational interdependence of galaxies in relation to their neighbors from the local group, as well as from the supercluster, is based on the interaction of atoms of baryonic matter with hidden matter.

Milky Way

Our home galaxy, the Milky Way, is a barred disk-shaped spiral. The core of the galaxy is made up of old stars - red giants. The Milky Way shares its local group with two neighboring galaxies: the Andromeda nebula and the Triangulum galaxy. The supercluster to which they belong is called the Virgo Supercluster.

In the local group of the Milky Way, in addition to the three large galaxies, there are about 40 dwarf satellite galaxies, which are attracted by the stronger gravitational fields of their large neighbors. There may be as many black holes and dark matter spaces in the Virgo Supercluster as there are galaxies. The exact number of stars in the Milky Way is unknown, but according to rough estimates there are 200 billion. The diameter of the Milky Way is one hundred thousand light years, and the average thickness of the disk is one thousand light years.

The youngest stars and their clusters are located closer to the surface of the disk, while the center of the galactic core, according to scientists, is a huge black hole, around which there is a very high concentration of stars. The main star of our system, the Sun, is located closer to the surface of the disk.

solar system

The solar system is 4.5 billion years old and is located in the shape of a disk. The heaviest element of the system is its center - the Sun; it accounts for almost all the mass, which determines the strong gravitational attraction. The eight planets orbiting it make up just 0.14% of the system's total mass. Earth belongs to the four small planets terrestrial group, along with Mars, Venus and Mercury. The remaining planets are called gas giants because they consist mostly of gases.

The science

Each person has his own idea of ​​what home is. For some it's a roof over their head, for others a home is... planet Earth, a rocky ball that plows through outer space along its closed path around the Sun.

No matter how big our planet may seem to us, it is just a grain of sand in giant star system, the size of which is difficult to imagine. This star system is the Milky Way galaxy, which can also rightfully be called our home.

Galaxy Sleeves

Milky Way- a spiral galaxy with a bar that runs through the center of the spiral. About two-thirds of all known galaxies are spiral, and two-thirds of them are barred. That is, the Milky Way is included in the list most common galaxies.

Spiral galaxies have arms that extend out from the center, like wheel spokes that twist in a spiral. Our solar system is located in the central part of one of the arms, which is called Orion's sleeve.

The Orion Arm was once thought to be a small "offshoot" of larger arms such as Perseus arm or Shield-Centauri arm. Not long ago, it was suggested that the Orion arm is indeed branch of the Perseus arm and does not leave the center of the galaxy.

The problem is that we cannot see our galaxy from the outside. We can only observe those things that are around us, and judge what shape the galaxy has, being, as it were, inside it. However, scientists were able to calculate that this sleeve has a length of approximately 11 thousand light years and thickness 3500 light years.


Supermassive black hole

The smallest supermassive black holes that scientists have discovered are approximately V 200 thousand times heavier than the sun. For comparison: ordinary black holes have the mass of just 10 times exceeding the mass of the Sun. At the center of the Milky Way is an incredibly massive black hole, the mass of which is difficult to imagine.



For the past 10 years, astronomers have been monitoring the activity of stars in orbit around the star. Sagittarius A, a dense region at the center of the spiral of our galaxy. Based on the movement of these stars, it was determined that in the center Sagittarius A*, which is hidden behind a dense cloud of dust and gas, there is a supermassive black hole whose mass 4.1 million times more than the mass of the Sun!

The animation below shows the actual motion of stars around a black hole. from 1997 to 2011 in the region of one cubic parsec in the center of our galaxy. When stars approach a black hole, they loop around it at incredible speeds. For example, one of these stars, S 0-2 moves at speed 18 million kilometers per hour: black hole first attracts her, and then sharply pushes her away.

Just recently, scientists observed how a cloud of gas approached a black hole and was torn to pieces by its massive gravitational field. Parts of this cloud were swallowed up by the hole, and the remaining parts began to resemble long thin noodles longer than 160 billion kilometers.

Magneticparticles

In addition to the presence of a supermassive all-consuming black hole, the center of our galaxy boasts incredible activity: old stars die, and new ones are born with enviable consistency.

Not long ago, scientists noticed something else at the galactic center - a stream of high-energy particles that extend a distance 15 thousand parsecs across the galaxy. This distance is approximately half the diameter of the Milky Way.

The particles are invisible to the naked eye, but magnetic imaging shows that particle geysers occupy approx. two thirds of the visible sky:

What is behind this phenomenon? For one million years, stars appeared and disappeared, feeding never stopping flow, directed towards the outer arms of the galaxy. The total energy of the geyser is a million times greater than the energy of a supernova.

Particles move at incredible speeds. Based on the structure of the particle flow, astronomers built model magnetic field , which dominates our galaxy.

Newstars

How often do new stars form in our galaxy? Researchers have been asking this question for many years. It was possible to map the areas of our galaxy where there is aluminum-26, an isotope of aluminum that appears where stars are born or die. Thus, it was possible to find out that every year in the Milky Way galaxy 7 new stars and approximately twice in a hundred years a large star explodes in a supernova.

The Milky Way Galaxy does not produce the largest number of stars. When a star dies, it releases such raw materials into space, like hydrogen and helium. Over hundreds of thousands of years, these particles coalesce into molecular clouds that eventually become so dense that their center collapses under their own gravity, thus forming a new star.


It looks like a kind of eco-system: death feeds new life . Particles from a particular star will be part of a billion new stars in the future. This is how things are in our galaxy, which is why it is evolving. This leads to the formation of new conditions under which the likelihood of the emergence of Earth-like planets increases.

Planets of the Milky Way galaxy

Despite the constant death and birth of new stars in our galaxy, their number has been calculated: the Milky Way is home to approximately 100 billion stars. Based on new research, scientists suggest that every star is orbited by at least one planet or more. That is, in our corner of the Universe there is only from 100 to 200 billion planets.

The scientists who came to this conclusion studied stars like red dwarfs of spectral type M. These stars are smaller than our Sun. They make up 75 percent of all the stars in the Milky Way. In particular, researchers paid attention to the star Kepler-32, which sheltered five planets.

How do astronomers discover new planets?

Planets, unlike stars, are difficult to detect because they do not emit their own light. We can say with certainty that there is a planet around a star only when it stands in front of his star and blocks out its light.


The planets of Kepler -32 behave exactly like exoplanets orbiting other M dwarf stars. They are located approximately at the same distance and have similar sizes. That is, the Kepler -32 system is typical system for our galaxy.

If there are more than 100 billion planets in our galaxy, how many of them are Earth-like planets? It turns out, not so much. There are dozens of different types of planets: gas giants, pulsar planets, brown dwarfs, and planets where molten metal rains from the sky. Those planets that consist of rocks can be located too far or too close to the star, so they are unlikely to resemble Earth.


The results of recent studies have shown that in our galaxy there are more terrestrial planets than previously thought, namely: from 11 to 40 billion. Scientists took as an example 42 thousand stars, similar to our Sun, and began to look for exoplanets that can orbit around them in a zone where it is not too hot and not too cold. Was found 603 exoplanets, among which 10 matched the search criteria.


By analyzing data about stars, scientists have proven the existence of billions of Earth-like planets that they have yet to officially discover. Theoretically, these planets are capable of maintaining temperatures for existence of liquid water on them, which, in turn, will allow life to arise.

Collision of galaxies

Even if new stars are constantly being formed in the Milky Way galaxy, it will not be able to increase in size, if he doesn't receive new material from somewhere else. And the Milky Way is really expanding.

Previously, we were not sure exactly how the galaxy manages to grow, but recent discoveries have suggested that the Milky Way is galaxy-cannibal, meaning it has consumed other galaxies in the past and will likely do so again, at least until some larger galaxy swallows it.

Using a space telescope "Hubble" and information obtained from photographs taken over seven years, scientists have discovered stars at the outer edge of the Milky Way that move in a special way. Instead of moving toward or away from the center of the galaxy like other stars, they appear to drift toward the edge. It is believed that this star cluster is all that remains of another galaxy that was absorbed by the Milky Way galaxy.


This collision apparently occurred several billion years ago and, most likely, it will not be the last. Considering the speed at which we are moving, our galaxy through 4.5 billion years will collide with the Andromeda galaxy.

Influence of satellite galaxies

Although the Milky Way is a spiral galaxy, it is not exactly a perfect spiral. At its center there is a kind of bulge, which appeared as a result of hydrogen gas molecules escaping from the flat disk of the spiral.


For years, astronomers have puzzled over why the galaxy has such a bulge. It is logical to assume that the gas is drawn into the disk itself, and does not escape out. The longer they studied this question, the more confused they became: the molecules of the bulge are not only pushed outward, but also vibrate at their own frequency.

What could cause this effect? Today, scientists believe that dark matter and satellite galaxies are to blame - Magellanic Clouds. These two galaxies are very small: taken together they make up only 2 percent of the total mass of the Milky Way. This is not enough to have an impact on him.

However, when dark matter moves through the clouds, it creates waves that apparently influence the gravitational attraction, strengthening it, and hydrogen under the influence of this attraction escapes from the center of the galaxy.


Magellanic Clouds orbit the Milky Way. The spiral arms of the Milky Way, under the influence of these galaxies, seem to sway in the place where they pass.

Twin galaxies

Although the Milky Way galaxy can be called unique in many respects, it is not very rare. Spiral galaxies predominate in the Universe. Considering that only in our field of vision are about 170 billion galaxies, we can assume that somewhere there are galaxies very similar to ours.

What if there is a galaxy somewhere - an exact copy of the Milky Way? In 2012, astronomers discovered such a galaxy. It even has two small moons that orbit it that exactly match our Magellanic Clouds. By the way, only 3 percent spiral galaxies have similar companions, whose lifespan is relatively short. The Magellanic Clouds are likely to dissolve in a couple of billion years.

To discover such a similar galaxy, with satellites, a supermassive black hole in the center and the same size, is incredible luck. This galaxy was named NGC 1073 and it's so similar to the Milky Way that astronomers are studying it to find out more about our own galaxy. For example, we can see it from the side and thus better imagine what the Milky Way looks like.

Galactic year

On Earth, a year is the time during which the Earth manages to make full revolution around the Sun. Every 365 days we return to the same point. Our solar system revolves in the same way around a black hole located at the center of the galaxy. However, it makes a full revolution in 250 million years. That is, since the dinosaurs disappeared, we have only made a quarter of a full revolution.


Descriptions of the solar system rarely mention that it moves through space, like everything else in our world. Relative to the center of the Milky Way, the solar system moves at a speed 792 thousand kilometers per hour. For comparison: if you were moving at the same speed, you could make trip around the world in 3 minutes.

The period of time during which the Sun manages to make a complete revolution around the center of the Milky Way is called galactic year. It is estimated that the Sun has lived only 18 galactic years.

In our age, illuminated by hundreds of electric lights, city residents have no opportunity to see the Milky Way. This phenomenon, which appears in our sky only during a certain period of the year, is observed only far from large settlements. In our latitudes it is especially beautiful in August. IN last month Summer, the Milky Way rises above the Earth in the form of a giant celestial arch. This weak, blurry strip of light appears denser and brighter in the direction of Scorpio and Sagittarius, and paler and more diffuse near Perseus.

Star Riddle

The Milky Way is an unusual phenomenon, the secret of which has not been revealed to people for a whole string of centuries. In the legends and myths of many peoples it was called differently. The amazing glow was the mysterious Star Bridge leading to heaven, the Road of the Gods and the magical Heavenly River carrying divine milk. At the same time, all peoples believed that the Milky Way was something sacred. The radiance was worshiped. Even temples were built in his honor.

Few people know that our New Year tree is an echo of the cults of people who lived in former times. Indeed, in ancient times it was believed that the Milky Way was the axis of the Universe or the World Tree, on whose branches stars ripened. That is why at the beginning of the annual cycle they decorated the Christmas tree. The earthly tree was an imitation of the eternally fruitful tree of heaven. Such a ritual gave hope for the favor of the gods and a good harvest. So great was the importance of the Milky Way for our ancestors.

Scientific assumptions

What is the Milky Way? The history of the discovery of this phenomenon goes back almost 2000 years. Plato also called this strip of light a seam connecting the celestial hemispheres. In contrast to this, Anaxagoras and Demoxide argued that the Milky Way (we’ll look at what color it is) is a kind of illumination of stars. She is the decoration of the night sky. Aristotle explained that the Milky Way is the glow of luminous lunar vapors in the air of our planet.

There were many other assumptions. Thus, the Roman Marcus Manilius said that the Milky Way is a constellation of small heavenly bodies. It was he who was closest to the truth, but he could not confirm his assumptions in those days when the sky was observed only with the naked eye. All ancient researchers believed that the Milky Way was part of the solar system.

Galileo's discovery

The Milky Way revealed its secret only in 1610. It was then that the first telescope was invented, which was used by Galileo Galilei. The famous scientist saw through the device that the Milky Way was a real cluster of stars, which, when viewed with the naked eye, merged into a continuous, faintly flickering strip. Galileo even managed to explain the heterogeneity of the structure of this band.

It was caused by the presence of not only star clusters in the celestial phenomenon. There are also dark clouds there. The combination of these two elements creates an amazing image of a night phenomenon.

William Herschel's discovery

The study of the Milky Way continued into the 18th century. During this period, its most active researcher was William Herschel. The famous composer and musician was engaged in the manufacture of telescopes and studied the science of stars. Herschel's most important discovery was the Great Plan of the Universe. This scientist observed the planets through a telescope and counted them in different parts of the sky. Research has led to the conclusion that the Milky Way is a kind of star island in which our Sun is located. Herschel even drew a schematic plan of his discovery. In the figure, the star system was depicted in the form of a millstone and had an elongated irregular shape. At the same time, the sun was inside this ring that surrounded our world. This is exactly how all scientists imagined our Galaxy until the beginning of the last century.

It was only in the 1920s that the work of Jacobus Kaptein was published, in which the Milky Way was described in the most detail. At the same time, the author gave a diagram of the star island, as similar as possible to the one that is currently known to us. Today we know that the Milky Way is a Galaxy that contains the Solar System, the Earth and those individual stars that are visible to humans with the naked eye.

Structure of galaxies

With the development of science, astronomical telescopes became more and more powerful. At the same time, the structure of the observed galaxies became increasingly clear. It turned out that they are not similar to each other. Some of them were incorrect. Their structure had no symmetry.

Elliptical and spiral galaxies have also been observed. What type of these types does the Milky Way belong to? This is our Galaxy, and, being inside, it is very difficult to determine its structure. However, scientists have found an answer to this question. Now we know what the Milky Way is. Its definition was given by researchers who established that it is a disk with an internal core.

general characteristics

The Milky Way is a spiral galaxy. Moreover, it has a bridge in the form of a huge interconnected gravitational force.

The Milky Way is believed to have existed for over thirteen billion years. This is the period during which about 400 billion constellations and stars, over a thousand huge gas nebulae, clusters and clouds were formed in this Galaxy.

The shape of the Milky Way is clearly visible on the map of the Universe. Upon examination, it becomes clear that this cluster of stars is a disk whose diameter is 100 thousand light years (one such light year is ten trillion kilometers). The thickness is 15 thousand, and the depth is about 8 thousand light years.

How much does the Milky Way weigh? This (the definition of its mass is very difficult task) it is not possible to calculate. Difficulties arise in determining the mass of dark matter, which does not interact with electromagnetic radiation. This is why astronomers definitively cannot answer this question. But there are rough calculations according to which the weight of the Galaxy ranges from 500 to 3000 billion solar masses.

The Milky Way is like all celestial bodies. It rotates around its axis, moving through the Universe. Astronomers point to the uneven, even chaotic movement of our Galaxy. This is explained by the fact that each of its constituent stellar systems and nebulae has its own speed, different from the others, and also different shapes and types of orbits.

What parts does the Milky Way consist of? These are the core and bridges, the disc and spiral arms, and the crown. Let's take a closer look at them.

Core

This part of the Milky Way is located in the core. There is a source of non-thermal radiation with a temperature of about ten million degrees. At the center of this part of the Milky Way is a compaction called a “bulge.” This is a whole string of old stars that moves along an elongated orbit. Most of these celestial bodies life cycle is already coming to an end.

In the central part of the core of the Milky Way is located. This section of outer space, the weight of which is equal to the mass of three million suns, has the most powerful gravity. Another black hole rotates around it, only smaller. Such a system creates such a force that nearby constellations and stars move along very unusual trajectories.

The center of the Milky Way has other features. Thus, it is characterized by a large cluster of stars. Moreover, the distance between them is hundreds of times smaller than that observed on the periphery of the formation.

It is also interesting that, observing the nuclei of other galaxies, astronomers note their bright shine. But why is it not visible in the Milky Way? Some researchers have even suggested that there is no core in our Galaxy. However, it was determined that in spiral nebulae there are dark layers that are interstellar accumulations of dust and gas. They are also found in the Milky Way. These huge dark clouds prevent the earthly observer from seeing the glow of the core. If such a formation did not interfere with earthlings, then we could observe the core in the form of a shining ellipsoid, the size of which would exceed the diameter of one hundred moons.

Modern telescopes, which are capable of operating in special ranges of the electromagnetic spectrum of radiation, have helped people answer this question. With the help of this modern technology, which was able to bypass the dust shield, scientists were able to see the core of the Milky Way.

Jumper

This element of the Milky Way crosses it central section and has a size of 27 thousand light years. The bridge consists of 22 million red stars of impressive age. Around this formation there is a gas ring, which contains a large percentage molecular oxygen. All this suggests that the Milky Way bar is the area where stars are formed in the greatest number.

Disk

This shape has the Milky Way itself, which is in constant rotational movement. Interestingly, the speed of this process depends on the distance of a particular area from the nucleus. So, in the very center it is equal to zero. At a distance of two thousand light years from the core, the rotation speed is 250 kilometers per hour.

The outer side of the Milky Way is surrounded by a layer of atomic hydrogen. Its thickness is 1.5 thousand light years.

On the outskirts of the Galaxy, astronomers have discovered the presence of dense gas clusters with a temperature of 10 thousand degrees. The thickness of such formations is several thousand light years.

Five spiral arms

These are another component of the Milky Way, located directly behind the gas ring. The spiral arms cross the constellations Cygnus and Perseus, Orion and Sagittarius, and Centaurus. These formations are unevenly filled with molecular gas. This composition introduces errors into the rules of rotation of the Galaxy.
The spiral arms emerge directly from the core of the star island. We observe them with the naked eye, calling the light stripe Milky Way.

The spiral branches are projected onto each other, which makes it difficult to understand their structure. Scientists suggest that such arms were formed due to the presence in the Milky Way of giant waves of rarefaction and compression of interstellar gas, which move from the core to the galactic disk.

Crown

The Milky Way has a spherical halo. This is his crown. This formation consists of individual stars and clusters of constellations. Moreover, the dimensions of the spherical halo are such that it extends beyond the boundaries of the Galaxy by 50 light years.

The Milky Way's corona typically contains low-mass and old stars, as well as dwarf galaxies and hot gas clusters. All these components move in elongated orbits around the nucleus, performing random rotation.

There is a hypothesis according to which the emergence of the corona was a consequence of the absorption of small galaxies by the Milky Way. According to astronomers, the age of the halo is about twelve billion years.

Location of stars

In a cloudless night sky, the Milky Way is visible from anywhere on our planet. However, only part of the Galaxy is accessible to human eyes, which is a system of stars located inside the Orion arm.

What is the Milky Way? The definition of all its parts in space becomes most clear if we consider a star map. In this case, it becomes clear that the Sun, which illuminates the Earth, is located almost on the disk. This is almost the edge of the Galaxy, where the distance from the core is 26-28 thousand light years. Moving at a speed of 240 kilometers per hour, the Sun spends 200 million years on one revolution around the core, so during its entire existence it traveled around the disk, circling the core, only thirty times.

Our planet is located in the so-called corotation circle. This is a place where the rotation speeds of the arms and stars are identical. This circle is characterized by an increased level of radiation. That is why life, as scientists believe, could only arise on that planet near which there are a small number of stars.

Our Earth was such a planet. It is located on the periphery of the Galaxy, in its quietest place. That is why on our planet for several billion years there was no global disasters, which often occur in the Universe.

Forecast for the future

Scientists suggest that in the future, collisions between the Milky Way and other galaxies are very likely, the largest of which is the Andromeda galaxy. But at the same time, it is not possible to talk specifically about anything. This requires knowledge of the magnitude lateral speeds extragalactic objects that are not yet accessible to modern researchers.

In September 2014, one of the models for the development of events was published in the media. According to it, four billion years will pass, and the Milky Way will absorb the Magellanic Clouds (Large and Small), and in another billion years it itself will become part of the Andromeda Nebula.

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