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Famous galaxies. The true dimensions of space or how many galaxies are in the universe

In modern astronomy, the most widely used is the very first classification of galaxies, proposed by Edwin Powell Hubble in 1926, and subsequently refined by him, and then by Gerard de Vaucouleurs and Alan Sandage.

This classification is based on the shape of known galaxies. According to it, all galaxies are divided into 5 main types:

Elliptical (E);

Spiral (S);

Barred spiral galaxies (SB);

Incorrect (Irr);

Galaxies too dim to be classified are designated by Hubble as Q.

In addition, the galaxy designations in this classification use numbers to indicate how oblate the elliptical galaxy is and letters to indicate how tightly the arms of spiral galaxies adhere to the core.

Graphically, this classification is represented as a series called the Hubble sequence (or the Hubble tuning fork due to the similarity of the circuit with this instrument).


Elliptical galaxies (type E) make up 13% of the total number of galaxies. They look like a circle or ellipse, the brightness of which quickly decreases from the center to the periphery. Elliptical galaxies are very diverse in shape: they can be either spherical or very oblate. In this regard, they are divided into 8 subclasses - from E0 (spherical shape, no compression) to E7 (highest compression).


Elliptical galaxies are the simplest in structure. They consist mainly of old red and yellow giants, red, yellow and white dwarfs. There is no dust matter in them. Star formation in galaxies of this type has not occurred for several billion years. There is almost no cold gas or cosmic dust in them. Rotation has been detected only in the most compressed of elliptical galaxies.

Spiral galaxies- the most numerous type: they make up about 50% of all observed galaxies. Most of the stars in a spiral galaxy are located within the galactic disk. The galactic disk exhibits a spiral pattern of two or more branches or arms twisting in one direction, extending from the center of the galaxy.



There are two types of spirals. In the first type, designated SA or S, the spiral arms extend directly from the central seal. In the second, they begin at the ends of an oblong formation, in the center of which there is an oval seal. It appears that the two spiral arms are connected by a bridge, which is why such galaxies are called crossed spirals; they are designated by the symbol SB.



Spiral galaxies differ in the degree of development of their spiral structure, which is marked in the classification by adding the letters a, b, c to the symbols S (or SA) and SB.

The arms of spiral galaxies are bluish in color because they contain many young giant stars. All spiral galaxies rotate at significant speeds, so stars, dust and gases are concentrated in a narrow disk (Population I stars). Rotation in the vast majority of cases occurs in the direction of twisting of the spiral branches.

Each spiral galaxy has a central condensation. The color of clusters of spiral galaxies is reddish-yellow, indicating that they consist mainly of stars of spectral classes G, K, and M (that is, the smallest and coolest).

The abundance of gas and dust clouds and the presence of bright blue giants of spectral classes O and B indicate active processes star formation occurring in the spiral arms of these galaxies.

The disk of spiral galaxies is immersed in a rarefied, faintly luminous cloud of stars - a halo. The halo consists of young Population II stars forming numerous globular clusters.

In some galaxies, the central part is spherical and glows brightly. This part is called the bulge (from the English bulge - thickening, swelling). The bulge consists of old Population II stars and, often, a supermassive black hole at the center. Other galaxies have a “stellar bar” in the central part.

The most famous spiral galaxies are our Galaxy Milky Way and the Andromeda nebula.

Lenticular galaxy(type S0) is an intermediate type between spiral and elliptical galaxies. In galaxies of this type, the bright central condensation (bulge) is highly compressed and looks like a lens, and the branches are absent or very faintly traced.



Lenticular galaxies consist of old giant stars, which is why their color is reddish. Two-thirds of lenticular galaxies, like ellipticals, do not contain gas; one-third has the same gas content as spiral galaxies. Therefore, star formation processes occur at a very slow pace. Dust in lenticular galaxies is concentrated near the galactic core. About 10% of known galaxies are lenticular galaxies.

For irregular or irregular galaxies (Ir) characterized by an irregular, patchy shape. Irregular galaxies are characterized by the absence of central densities and symmetrical structure, as well as low luminosity. Such galaxies contain a lot of gas (mainly neutral hydrogen) - up to 50% of them total mass. About 25% of all star systems belong to this type.


Irregular galaxies are divided into 2 large groups. The first of these, designated Irr I, includes galaxies with a hint of a certain structure. The Irr I division is not final: for example, if the galaxy under study shows a semblance of spiral arms (characteristic of S-type galaxies), the galaxy receives the designation Sm or SBm (has a bar in its structure); if such a phenomenon is not observed, the designation is Im.

The second group of irregular galaxies (Irr II) includes all other galaxies with a chaotic structure.

There is also a third group of irregular galaxies - dwarf galaxies, designated as dI or dIrrs. Dwarf irregular galaxies are believed to be similar to the earliest galactic formations that existed in the Universe. Some are small spiral galaxies destroyed by the tidal forces of more massive companions.

Typical representatives of such galaxies are the Large and Small Magellanic Clouds. In the past, the Large and Small Magellanic Clouds were thought to be irregular galaxies. However, they were later discovered to have a helical structure with a bar. Therefore, these galaxies were reclassified as SBm, the fourth type of barred spiral galaxy.

Galaxies that have certain individual characteristics, which do not allow them to be classified into any of the classes listed above are called peculiar.

An example of a peculiar galaxy is the radio galaxy Centaurus A (NGC 5128).

Hubble's classification is this moment the most common, but not the only one. In particular, the de Vaucouleurs System, which is a more expanded and revised version of the Hubble classification, and the Yerkes System, in which galaxies are grouped depending on their spectra, shape and degree of concentration towards the center, are widely used.

The outer space around us is not just lonely stars, planets, asteroids and comets sparkling in the night sky. Space is a huge system where everything is in close interaction with each other. Planets are grouped around stars, which in turn gather into a cluster or nebula. These formations can be represented by single luminaries, or they can number hundreds, thousands of stars, forming larger-scale universal formations - galaxies. Our star country, the Milky Way galaxy, is only a small part of the vast Universe, in which other galaxies also exist.

The universe is constantly in motion. Any object in space is part of a particular galaxy. Following the stars, galaxies also move, each of which has its own size, a specific place in the dense universal order and its own trajectory of movement.

What is the real structure of the Universe?

For a long time, humanity's scientific ideas about space were built around the planets of the solar system, stars and black holes that inhabit our stellar home - the Milky Way galaxy. Any other galactic object detected in space using telescopes was automatically included in the structure of our galactic space. Accordingly, there was no idea that the Milky Way is not the only universal formation.

Limited technical capabilities did not allow us to look further, beyond the Milky Way, where, according to conventional wisdom, the void begins. Only in 1920, the American astrophysicist Edwin Hubble was able to find evidence that the Universe is much larger and, along with our galaxy, there are other, large and small galaxies in this huge and endless world. There is no real boundary of the Universe. Some objects are located quite close to us, only a few million light years from Earth. Others, on the contrary, are located in the far corner of the Universe, being out of sight.

Almost a hundred years have passed and the number of galaxies today is already estimated at hundreds of thousands. Against this background, our Milky Way looks not at all so huge, if not quite tiny. Today, galaxies have already been discovered whose dimensions are difficult even to determine. mathematical analysis. For example, the largest galaxy in the Universe, IC 1101, has a diameter of 6 million light years and consists of more than 100 trillion stars. This galactic monster is located more than a billion light years from our planet.

The structure of such a huge formation, which is the Universe on a global scale, is represented by emptiness and interstellar formations - filaments. The latter, in turn, are divided into superclusters, intergalactic clusters and galactic groups. The smallest link of this huge mechanism is the galaxy, represented by numerous star clusters - arms and gas nebulae. It is assumed that the Universe is constantly expanding, thereby causing galaxies to move with enormous speed in the direction from the center of the Universe to the periphery.

If we imagine that we are observing space from our Milky Way galaxy, which is supposedly located at the center of the universe, then a large-scale model of the structure of the Universe will look like this.

Dark matter - aka emptiness, superclusters, clusters of galaxies and nebulae - are all consequences of the Big Bang, which marked the beginning of the formation of the Universe. Over the course of a billion years, its structure undergoes a transformation, the shape of galaxies changes, as some stars disappear, swallowed up by black holes, while others, on the contrary, transform into supernovae, becoming new galactic objects. Billions of years ago, the arrangement of galaxies was completely different from what we see now. One way or another, against the background of constant astrophysical processes occurring in space, we can draw certain conclusions that our Universe does not have a constant structure. All space objects are in constant motion, changing their position, size and age.

To date, thanks to the Hubble telescope, it has been possible to detect the location of the galaxies closest to us, establish their sizes and determine the location relative to our world. Through the efforts of astronomers, mathematicians and astrophysicists, a map of the Universe has been compiled. Single galaxies have been identified, but for the most part, such large universal objects are grouped in groups of several dozen in a group. The average size galaxies in such a group are 1-3 million light years away. The group to which our Milky Way belongs contains 40 galaxies. In addition to groups, there are a huge number of dwarf galaxies in intergalactic space. As a rule, such formations are satellites of larger galaxies, such as our Milky Way, Triangulum or Andromeda.

Until recently, the dwarf galaxy “Segue 2”, located 35 kiloparsecs from our star, was considered the smallest galaxy in the Universe. However, in 2019, Japanese astrophysicists identified an even smaller galaxy - Virgo I, which is a satellite of the Milky Way and is located at a distance of 280 thousand light years from Earth. However, scientists believe that this is not the limit. There is a high probability that galaxies of much more modest sizes exist.

After groups of galaxies come clusters, regions of outer space in which there are up to hundreds of galaxies various types, shapes and sizes. The clusters are colossal in size. As a rule, the diameter of such a universal formation is several megaparsecs.

A distinctive feature of the structure of the Universe is its weak variability. Despite the enormous speeds at which galaxies move in the Universe, they all remain part of one cluster. Here the principle of preserving the position of particles in space, which is affected by the dark matter formed as a result of big bang. It is assumed that, under the influence of these voids filled with dark matter, clusters and groups of galaxies continue to move in the same direction for billions of years, neighboring each other.

The largest formations in the Universe are galactic superclusters, which unite groups of galaxies. The most famous supercluster is the Great Clown Wall, an object of universal scale, stretching over 500 million light years. The thickness of this supercluster is 15 million light years.

Under current conditions spacecraft and technology do not allow us to consider the Universe to its full depth. We can only detect superclusters, clusters and groups. In addition, our space has giant voids, bubbles of dark matter.

Steps towards exploring the Universe

A modern map of the Universe allows us not only to determine our location in space. Today, thanks to the availability of powerful radio telescopes and the technical capabilities of the Hubble telescope, man has been able not only to approximately calculate the number of galaxies in the Universe, but also to determine their types and varieties. Back in 1845, British astronomer William Parsons, using a telescope to study clouds of gas, was able to reveal the spiral nature of the structure of galactic objects, focusing on the fact that in different areas the brightness of star clusters can be greater or lesser.

A hundred years ago, the Milky Way was considered the only known galaxy, although the presence of other intergalactic objects was mathematically proven. Our space yard got its name back in ancient times. Ancient astronomers, looking at the myriads of stars in the night sky, noticed characteristic feature their locations. The main cluster of stars was concentrated along an imaginary line, reminiscent of a path of splashed milk. Milky Way Galaxy, celestial bodies Another well-known galaxy, Andromeda, are the very first universal objects from which the study of outer space began.

Our Milky Way has the complete set of all galactic objects that a normal galaxy should have. There are clusters and groups of stars here, the total number of which is approximately 250-400 billion. There are clouds of gas in our galaxy that form arms, there are black holes and solar systems similar to ours.

At the same time, the Milky Way, like Andromeda and Triangulum, are only a small part of the Universe, part of the local group of the Virgo supercluster. Our galaxy has the shape of a spiral, where the bulk of star clusters, gas clouds and other space objects move around the center. The diameter of the outer spiral is 100 thousand light years. The Milky Way is not a large galaxy by cosmic standards, its mass is 4.8 x 1011 Mʘ. Our Sun is also located in one of the arms of Orion Cygnus. The distance from our star to the center of the Milky Way is 26,000 ± 1,400 light years. years.

For a long time, it was believed that the Andromeda nebula, one of the most popular among astronomers, is part of our galaxy. Subsequent studies of this part of space provided irrefutable evidence that Andromeda is an independent galaxy, and much larger than the Milky Way. Images obtained using telescopes showed that Andromeda has its own core. There are also clusters of stars here and there are nebulae of their own, moving in a spiral. Each time, astronomers tried to look deeper and deeper into the Universe, exploring vast areas of outer space. The number of stars in this universal giant is estimated at 1 trillion.

Through the efforts of Edwin Hubble, it was possible to establish approximate distance to Andromeda, which could not possibly be part of our galaxy. This was the first galaxy to be studied so closely. Subsequent years brought new discoveries in the field of exploration of intergalactic space. The part of the Milky Way galaxy in which ours is located has been studied more thoroughly. solar system. Since the middle of the 20th century, it has become clear that in addition to our Milky Way and the well-known Andromeda, there are a huge number of other formations on a universal scale in space. However, order required the ordering of outer space. While stars, planets and other cosmic objects could be classified, the situation with galaxies was more complicated. This was due to the enormous size of the areas of outer space under study, which were not only difficult to study visually, but also to evaluate at the level of human nature.

Types of galaxies in accordance with the accepted classification

Hubble was the first to take such a step, making an attempt in 1962 to logically classify the galaxies known at that time. Classification was carried out based on the shape of the objects under study. As a result, Hubble managed to arrange all the galaxies into four groups:

  • the most common type are spiral galaxies;
  • followed by elliptical spiral galaxies;
  • with galaxy bar (bar);
  • irregular galaxies.

It should be noted that our Milky Way is a typical spiral galaxy, but there is one “but”. Recently, the presence of a jumper - a bar, which is present in the central part of the formation - has been revealed. In other words, our galaxy does not originate from the galactic core, but flows out of the bridge.

Traditionally, a spiral galaxy looks like a flat, spiral-shaped disk, which necessarily contains a bright center—the galactic core. There are most of these galaxies in the Universe and they are designated by the Latin letter S. In addition, there is a division of spiral galaxies into four subgroups - So, Sa, Sb and Sc. Small letters indicate the presence of a bright core, the absence of arms, or, conversely, the presence of dense arms covering the central part of the galaxy. In such arms there are clusters of stars, groups of stars that include our Solar System, and other space objects.

The main feature of this type is the slow rotation around the center. The Milky Way completes a revolution around its center every 250 million years. The spirals located closer to the center consist mainly of clusters of old stars. The center of our galaxy is a black hole, around which all the main movement occurs. The length of the path, according to modern estimates, is 1.5-25 thousand light years towards the center. During their existence, spiral galaxies can merge with other smaller universal formations. Evidence of such collisions in earlier periods is the presence of halos of stars and halos of clusters. A similar theory underlies the theory of the formation of spiral galaxies, which were the result of the collision of two galaxies located in the neighborhood. The collision could not pass without a trace, giving a general rotational impulse to the new formation. Next to the spiral galaxy there is a dwarf galaxy, one, two or several at once, which are satellites of a larger formation.

Close in structure and composition to spiral galaxies are elliptical spiral galaxies. These are huge, the largest universal objects, including a large number of superclusters, clusters and groups of stars. In the largest galaxies, the number of stars exceeds tens of trillions. The main difference between such formations is their highly extended shape in space. The spirals are arranged in the shape of an ellipse. Elliptical spiral galaxy M87 is one of the largest in the Universe.

Barred galaxies are much less common. They account for approximately half of all spiral galaxies. Unlike spiral formations, such galaxies originate from a bridge called a bar, which flows from the two brightest stars located in the center. A striking example Such formations are our Milky Way and the Large Magellanic Cloud galaxy. Previously, this formation was classified as irregular galaxies. The appearance of the jumper is currently one of the main areas of research in modern astrophysics. According to one version, a nearby black hole sucks and absorbs gas from neighboring stars.

The most beautiful galaxies in the Universe are the types of spiral and irregular galaxies. One of the most beautiful is the Whirlpool Galaxy, located in celestial constellation Hound Dogs. IN in this case the center of the galaxy and the spirals rotating in the same direction are clearly visible. Irregular galaxies are chaotically located superclusters of stars that do not have a clear structure. A striking example of such a formation is the galaxy number NGC 4038, located in the constellation Raven. Here, along with huge gas clouds and nebulae, you can see a complete lack of order in the arrangement of space objects.

conclusions

You can study the Universe endlessly. Every time, with the advent of new technical means, a man lifts the curtain of space. Galaxies are the most incomprehensible objects in the world for the human mind. outer space, both from a psychological point of view and looking back at science.

If you have any questions, leave them in the comments below the article. We or our visitors will be happy to answer them

Galaxies are huge rotating cities of stars. There are at least 100 billion galaxies in the Universe, separated from each other by unimaginable distances of practically empty space. Without a telescope, only three galaxies and part of our own Milky Way Galaxy can be observed from Earth. Two of them are called the Magellanic Clouds.

They received this name in honor of the Portuguese navigator Ferdinand Magellan. When Magellan's ships sailed to southern seas in 1519, crew members saw two dimly glowing galaxies in the sky. They brought the news of this with them to Europe.

Nearest galaxies to Earth

Magellanic Clouds Galaxy

The Magellanic Clouds really look like two small clouds - dim and solid. These two small galaxies orbit the larger Milky Way. So the Magellanic Clouds are our closest neighbor. How small are these galaxies? One of them contains 15 billion suns, the other only about 5 billion. For comparison, we can say that there are about 200 billion stars in our Galaxy.

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Other planets and planetary systems


Galaxy Andromeda Nebula

The third galaxy that can be observed with the naked eye is the Andromeda Nebula. It is a spiral galaxy similar to the Milky Way. The Andromeda nebula is located 2.2 million light years away from us. A light year is the distance light travels in one year, traveling 300,000 kilometers per second. Over the course of a year, this amounts to about 9.6 trillion kilometers.

This means that the Andromeda nebula is 211200000000000000000 kilometers away, and that it takes light 2.2 million years to travel from the Andromeda nebula to Earth, and it also means that we are seeing the galaxy as it was for 2.2 million years back.

The starry sky has attracted people's gaze since ancient times. The best minds of all nations tried to comprehend our place in the Universe, imagine and justify its structure. Scientific progress allowed us to move in the study of the vast expanses of space from romantic and religious constructions to logically verified theories based on numerous factual materials. Now any schoolchild has an idea of ​​what our Galaxy looks like according to the latest research, who, why and when gave it such a poetic name and what its expected future is.

origin of name

The expression “Milky Way Galaxy” is essentially a tautology. Galactikos roughly translated from ancient Greek means “milk”. This is how the inhabitants of the Peloponnese called the cluster of stars in the night sky, attributing its origin to the hot-tempered Hera: the goddess did not want to feed Hercules, the illegitimate son of Zeus, and in anger splashed breast milk. The drops formed a star trail, visible on clear nights. Centuries later, scientists discovered that the observed luminaries are only a tiny part of the existing ones. celestial bodies. They gave the name Galaxy or the Milky Way system to the space of the Universe in which our planet is located. After confirming the assumption of the existence of other similar formations in space, the first term became universal for them.

A look from the inside

Scientific knowledge about the structure of the part of the Universe, including the Solar System, learned little from the ancient Greeks. Understanding of what our Galaxy looks like has evolved from Aristotle's spherical universe to modern theories that include black holes and dark matter.

The fact that Earth is part of the Milky Way system imposes certain limitations on those trying to figure out what shape our Galaxy has. To answer this question unambiguously, a view from the outside is required, and at a great distance from the object of observation. Now science is deprived of such an opportunity. A kind of substitute for an outside observer is the collection of data on the structure of the Galaxy and its correlation with the parameters of other space systems available for study.

The information collected allows us to say with confidence that our Galaxy has the shape of a disk with a thickening (bulge) in the middle and spiral arms diverging from the center. The latter contain the most bright stars systems. The diameter of the disk is more than 100 thousand light years.

Structure

The center of the Galaxy is hidden by interstellar dust, making it difficult to study the system. Radio astronomy methods help to cope with the problem. Waves of a certain length easily overcome any obstacles and allow you to obtain the much desired image. Our Galaxy, according to the data obtained, has an inhomogeneous structure.

Conventionally, we can distinguish two elements connected with each other: the halo and the disk itself. The first subsystem has the following characteristics:

  • the shape is a sphere;
  • its center is considered to be a bulge;
  • the highest concentration of stars in the halo is characteristic of its middle part; as you approach the edges, the density decreases greatly;
  • The rotation of this zone of the galaxy is quite slow;
  • the halo mainly contains old stars with relatively low mass;
  • a significant space of the subsystem is filled with dark matter.

The density of stars in the galactic disk greatly exceeds the halo. In the sleeves there are young and even just emerging

Center and core

The “heart” of the Milky Way is located in Without studying it, it is difficult to fully understand what our Galaxy is like. The name "core" in scientific works either refers only to the central region with a diameter of only a few parsecs, or includes a bulge and a gas ring, believed to be the birthplace of stars. In what follows, the first version of the term will be used.

Visible light has difficulty penetrating the center of the Milky Way because it encounters a lot of cosmic dust, hiding what our Galaxy looks like. Photos and images taken in the infrared range significantly expand astronomers' knowledge of the nucleus.

Data on the characteristics of radiation in the central part of the Galaxy led scientists to believe that there is a black hole at the core of the nucleus. Its mass is more than 2.5 million times the mass of the Sun. Around this object, according to researchers, another, but less impressive in its parameters, black hole rotates. Modern knowledge about the structural features of space suggests that such objects are located in the central part of most galaxies.

Light and darkness

The combined influence of black holes on the motion of stars makes its own adjustments to the way our Galaxy looks: it leads to specific changes in orbits that are not typical for cosmic bodies, for example, near the Solar system. The study of these trajectories and the relationship between the speed of movement and the distance from the center of the Galaxy formed the basis of the now actively developing theory of dark matter. Its nature is still shrouded in mystery. The presence of dark matter, which presumably makes up the vast majority of all matter in the Universe, is registered only by the effect of gravity on orbits.

If you dispel all cosmic dust, what the core hides from us, an amazing picture will open to our eyes. Despite the concentration of dark matter, this part of the Universe is full of light emitted a huge amount stars There are hundreds of times more of them per unit of space here than near the Sun. About ten billion of them form a galactic bar, also called a bar, of an unusual shape.

Space nut

Studying the center of the system in the long-wavelength range allowed us to obtain a detailed infrared image. Our Galaxy, as it turns out, has a structure at its core that resembles a peanut in a shell. This “nut” is the bridge, which includes more than 20 million red giants (bright, but less hot stars).

The spiral arms of the Milky Way radiate from the ends of the bar.

The work associated with the discovery of the “peanut” at the center of the star system not only shed light on the structure of our Galaxy, but also helped to understand how it developed. Initially, in the space of space there was an ordinary disk, in which a jumper formed over time. Under the influence of internal processes, the bar changed its shape and began to resemble a nut.

Our home on the space map

The activity occurs both in the bar and in the spiral arms that our Galaxy possesses. They were named after the constellations where sections of the branches were discovered: the arms of Perseus, Cygnus, Centaurus, Sagittarius and Orion. Near the latter (at a distance of at least 28 thousand light years from the core) is the Solar System. This area has certain characteristics that, according to experts, made possible the emergence of life on Earth.

The galaxy and our solar system rotate along with it. The patterns of movement of individual components do not coincide. stars are sometimes included in the spiral branches, sometimes separated from them. Only luminaries lying on the boundary of the corotation circle do not make such “travels”. These include the Sun, protected from powerful processes constantly occurring in the arms. Even a slight shift would negate all other benefits for the development of organisms on our planet.

The sky is in diamonds

The Sun is just one of many similar bodies that our Galaxy is full of. Stars, single or grouped, total number exceed, according to the latest data, 400 billion. The closest to us, Proxima Centauri, is part of a system of three stars along with slightly more distant Alpha Centauri A and Alpha Centauri B. The brightest point of the night sky, Sirius A, is located in Its luminosity, according to various sources, exceeds the solar one in 17-23 times. Sirius is also not alone; he is accompanied by a satellite bearing a similar name, but marked B.

Children often begin to get acquainted with what our Galaxy looks like by searching the sky North Star or Alpha Ursa Minor. She owes her popularity to her position above North Pole Earth. The luminosity of Polaris is significantly higher than Sirius (almost two thousand times brighter than the Sun), but it cannot challenge the rights of Alpha Canis Major for the title of the brightest due to its distance from Earth (estimated from 300 to 465 light years).

Types of luminaries

Stars differ not only in luminosity and distance from the observer. Each is assigned a certain value (the corresponding parameter of the Sun is taken as a unit), the degree of surface heating, and color.

Supergiants have the most impressive sizes. The highest concentration of a substance per unit volume differs neutron stars. The color characteristic is inextricably linked with temperature:

  • reds are the coldest;
  • heating the surface to 6,000º, like the Sun, gives rise to a yellow tint;
  • white and blue luminaries have a temperature of more than 10,000º.

May vary and reach a maximum shortly before its collapse. Supernova explosions make a huge contribution to understanding what our Galaxy looks like. Photos of this process taken by telescopes are amazing.
The data collected on their basis helped to reconstruct the process that led to the outbreak and predict the fate of a number of cosmic bodies.

The future of the Milky Way

Our Galaxy and other galaxies are constantly in motion and interacting. Astronomers have found that the Milky Way has repeatedly absorbed its neighbors. Similar processes are expected in the future. Over time, it will include the Magellanic Cloud and a number of other dwarf systems. The most impressive event is expected in 3-5 billion years. This will be a collision with the only neighbor that is visible from Earth with the naked eye. As a result, the Milky Way will become an elliptical galaxy.

The endless expanses of space amaze the imagination. It is difficult for the average person to realize the scale of not only the Milky Way or the entire Universe, but even the Earth. However, thanks to the achievements of science, we can imagine at least approximately what kind of grandiose world we are part of.

Events

Astronomers have discovered largest spiral galaxy, the larger of which no one has ever seen. Moreover, they claim that currently we are witnessing the birth of another galaxy as a result of the collision of two galaxies.

Incredible spiral galaxy NGC 6872 was noticed by astronomers several decades ago and was considered one of the largest star systems Universe, however, only recently it was proven that it is the largest spiral of all known to science.

Features of the largest galaxy NGC 6872

The width of the galaxy NGC 6872 is 522 thousand light years- this is 5 times greater than the width of our galaxy Milky Way. A relatively recent collision with another galaxy likely caused fresh stars began to appear in one of her sleeves, which will ultimately lead to the formation of a new galaxy.

These discoveries were made by an international group of scientists from Brazil, Chile and the USA, who examined images from the space telescope NASA GALEX. This telescope is capable of detecting ultraviolet rays the youngest and hottest stars.

Galaxy NGC 6872 in all its glory

Unusual size and appearance galaxies NGC 6872 are associated with its interaction with a smaller galaxy IC 4970 , whose mass is only one fiftieth mass of the giant galaxy. This odd couple located at a distance of 212 million light years from Earth in southern constellation Pavo.

Astronomers believe that large galaxies, including our own, grow due to mergers with other galaxies. These processes last for billions of years, during which some galaxies absorb other, smaller ones.

The yellow circle shows a cluster of young stars that form a fresh galaxy

An interesting fact is that when the galaxies NGC 6872 and IC 4970 interact, not one large one is formed, but one very small galaxy. The northeastern arm of NGC 6872 stands out quite strongly in the image; new stars are unlikely to form here, but at its other end (at the northwestern end) there is a fainter object that looks like a dwarf galaxy, the researchers said.

By analyzing the energy distribution, the team discovered that the two arms of the galaxy NGC 6872 consist of stars of different ages . The youngest stars are located in the region of the northwestern arm, that is, in the region of the proposed new dwarf galaxy. The stars get older closer to the center of NGC 6872.


The most beautiful galaxies in the Universe

Andromeda Galaxy

Distance from Earth: 2.52 million light years

This galaxy is most nearby galaxy to our own, and also one of the most beautiful. It can be seen on a clear night in the area of ​​the Andromeda constellation. Previously it was believed that this galaxy was the largest in the nearby group of galaxies, but later it turned out that the Milky Way is much more massive.

This is what the sky will look like in 3.75 billion years, when the Andromeda Galaxy approaches our Milky Way.


Galaxy Sombrero

Distance from Earth: 28 million light years

This spiral galaxy is located in the region Virgo constellation. She has bright core, an incredibly large central part and a brightly highlighted smooth dust rim like a ring. Galaxy in appearance somewhat reminiscent of a sombrero, that's why it got its name. At the center of this galaxy there is large black hole, which is of great interest to astronomers.

This galaxy is visible even with the help of amateur telescopes


Group of galaxies – Antennae Galaxies

Distance from Earth: 45 million light years

In the constellation of the Raven you can see a curious cluster of galaxies that forms incredible space landscapes. This galaxy is currently passing starburst, that is, stars are formed in it at a relatively high speed.

Spectacular landscape of the Antennae galaxies


Black Eye Galaxy in the constellation Coma Berenices

Distance from Earth: 17 million light years

Galaxy M 64 or as it is often called Black eye, very unusual the way it happens from 2 stuck together galaxies, rotating in different directions. It has an impressive dark rim of dust that stands out against the bright core.

The Black Eye Galaxy is very popular among amateur astronomers


Large Whirlpool Galaxy

Distance from Earth: 23 million light years

Also known as Messier 51, this galaxy was named whirlpool because of its resemblance to a whirlpool. She is in the area constellation Canes Venatici and has a small companion - the galaxy NGC 5195. This galaxy is one of most famous spiral galaxies and is easily visible in amateur telescopes.

The Whirlpool Galaxy and its companion are best observed in the spring and summer


Strange galaxy NGC 3314A in the constellation Hydra

Distance from Earth: 117 and 140 million light years

In fact, these are 2 galaxies: NGC 3314A and B, which did not collide with each other, but simply overlap one another from our vantage point.

Overlapping galaxies


Spiral galaxy M 81 - Bode galaxy in the constellation Ursa Major

Distance from Earth: 11.7 million light years

Named after Johann Bode, the German astronomer who discovered it, this galaxy is one of the most beautiful galaxies known to us. It is located in the area constellations Big Dipper and is quite visible. In addition to M81, the constellation also contains 33 galaxies.

Bode's Galaxy Boasts Nearly Perfect Sleeves


Beautiful ring galaxy Hoag's Object in the constellation Serpens

Distance from Earth: 600 million light years

Named after the scientist who discovered it in 1950, a ring-shaped galaxy has unusual structure and appearance. This galaxy was the first ringed galaxy known science. The approximate diameter of her ring is 100 thousand light years.

The outer side of the ring is dominated by bright blue stars, and closer to the center there is a ring of more reddish stars, which are probably much older. Between these rings is a darker ring. How exactly was it formed Hoag's object, is unknown to science, although several other similar objects are known.

Hoag's Object photographed by the Hubble Space Telescope in July 2001


Cigar Galaxy in the constellation Ursa Major

Distance from Earth: 12 million light years

Galaxy M 82 or, as it is also called, Cigar is a satellite of another galaxy - M 81. It is notable for the fact that it is located in its center supermassive black hole, around which two more less massive black holes revolve. Also in this galaxy, stars are formed at a relatively high rate. In the center of this galaxy, young stars are born 10 times faster than within our Milky Way galaxy.

The incredibly beautiful Cigar Galaxy


Galaxy NGC 2787 in the constellation Ursa Major

Distance from Earth: 24 million light years

Lenticular galaxy no. NGC 2787 is middle link between elliptical and spiral galaxies and looks very unusual: its sleeves are barely visible, and there is a bright core in the center.

Galaxy NGC 2787. Image taken using the Hubble Space Telescope.