Of the large stellar systems nearby is the Andromeda Nebula (M31) - a spiral galaxy 2.6 times larger than our home - the Milky Way galaxy: its diameter is 260 thousand light years. The Andromeda Nebula is located at a distance of 2.5 million light years (772 kiloparsecs) from us, and its mass is 300 billion solar masses. It includes about a trillion stars (for comparison: the Milky Way contains about 100 billion stars).
The Andromeda Nebula is the most distant space object from us, which can be observed in the starry sky (northern hemisphere) with the naked eye, even in urban lighting conditions - it looks like a luminous blurry oval. It should be remembered that due to the fact that the light from the Andromeda galaxy goes to us for 2.5 million years, we see it as it was 2.5 million years ago, and do not know how it looks in the real moment.
B - Andromeda galaxy in ultraviolet rays
Astronomers have found that the Andromeda Galaxy and our Galaxy are approaching each other at a speed of 100-140 km / s. In about 3-4 billion years, it is possible that they will collide and then they will merge into one giant galaxy. Those who are worried about the fate of the solar system as a result of this collision, we hasten to reassure: no impact on the sun and the planets, most likely, will occur. The processes of merging galaxies are not accompanied by catastrophic stellar collisions, since the distances between the stars are very large compared to the size of the stars themselves.
However, one should not think that the process of merging galaxies, stretched over millions of years, occurs without dramatic effects. When two galaxies approach each other, clouds of interstellar gas come into contact first. Due to the rapid interpenetration, their density increases sharply, they heat up, and the growing pressure turns these gas and dust clouds into centers for the formation of new stars. A violent, explosive process of star formation begins, accompanied by flares, explosions and the ejection of monstrously extended jets of dust and gas.
However, back to our neighbors. The second closest spiral galaxy to us is M33. It is located in the constellation Triangulum and is 2.4 million light years distant from us. In diameter, it is 2 times smaller than the Milky Way and 4 times smaller than the Andromeda galaxy. She can also be seen with the naked eye, but only on a moonless night and outside the city. It looks like a dull, hazy speck between the α of Triangle and τ of Pisces.
A - the position of the galaxy in the starry sky
B - Galaxy of the Triangle (NASA photo in ultraviolet and visible range)
All other galaxies in our immediate neighborhood are dwarf elliptical and irregular galaxies. Of the nearby irregular galaxies, two are of greatest interest: Large and Small Magellanic Clouds.
The Magellanic Clouds are satellites of our Milky Way Galaxy. They are also visible to the naked eye, however, only in the southern hemisphere. The Large Magellanic Cloud is located in the constellation Dorado. It is 170 thousand light-years (50 kiloparsecs) distant from us, 20 thousand light-years in diameter, and contains about 30 billion stars. Despite belonging to the type of irregular galaxies, the Large Magellanic Cloud has a structure close to intersected spiral galaxies. It contains all the types of stars known in the Milky Way. Another interesting object was discovered in the Large Magellanic Cloud - one of the brightest among the known gas and dust complexes with a length of 700 light years - tarantula nebula, a hotbed of violent star formation.
Survey with the TRAPPIST telescope (La Silla Observatory, Chile)
The Small Magellanic Cloud is 3 times smaller than the Large one and also resembles a crossed spiral galaxy. It is located in the constellation Toucan, adjacent to Dorado. The distance from us to this galaxy is 210 thousand light years (60 kiloparsecs).
The Magellanic Clouds are surrounded by a common shell of neutral hydrogen called the Magellanic System.
Both Magellanic Clouds are victims galactic cannibalism from the side of the Milky Way: the gravitational influence of our Galaxy gradually destroys them and attracts the matter of these galaxies to itself. Hence the irregular shape of the Magellanic Clouds. Experts believe that these are the remnants of two small galaxies in the process of gradual disappearance. According to astronomers, in the next 10 billion years, the Milky Way will completely absorb all the matter of the Magellanic Clouds. Between the Magellanic clouds themselves, similar processes take place: due to its gravity, the Large Magellanic cloud "steals" millions of stars from the Small Magellanic cloud. Perhaps this fact explains the high star-forming activity in the Tarantula Nebula: this region is located just in the path of the gas flow, which is pulled by the gravity of the Large Magellanic Cloud from the Small.
Thus, using the example of what is happening in the vicinity of our Galaxy, you can again make sure that the merger of galaxies and the absorption of small galaxies by larger ones is quite a common phenomenon in galactic life.
Our Galaxy, the Andromeda Galaxy and the Triangulum Galaxy make up a group of galaxies linked by gravitational interactions. They call her Local group of galaxies... The Local Group size is 1.5 megaparsecs across. In addition to three large spiral galaxies, the Local Group includes more than 50 dwarf and irregular (in shape) galaxies. So, the Andromeda galaxy has at least 19 satellite galaxies, our Galaxy has 14 satellites (as of 2005). In addition to them, the Local Group includes other dwarf galaxies that are not satellites of large galaxies.
A galaxy is called a large formation of stars, gas, dust, which are held together by the force of gravity. These largest compounds in the universe can vary in shape and size. Most of the space objects are part of a particular galaxy. These are stars, planets, satellites, nebulae, black holes and asteroids. Some of the galaxies have a lot of invisible dark energy. Due to the fact that the galaxies are divided by empty space, they are figuratively called oases in the cosmic desert ..
| Elliptical galaxy | Spiral galaxy | Wrong galaxy | |
|---|---|---|---|
| Spheroidal component | Whole galaxy | there is | Very weak |
| Star disk | No or mild | Main component | Main component |
| Gas and dust disk | Not | there is | there is |
| Spiral branches | No or only near the core | there is | Not |
| Active nuclei | Meet | Meet | Not |
| 20% | 55% | 5% |
Our galaxy
The closest star to us, the Sun, belongs to one billion stars in the Milky Way galaxy. Looking at the starry night sky, it is hard not to notice a wide stripe covered with stars. The ancient Greeks called the cluster of these stars the Galaxy.
If we had the opportunity to look at this stellar system from the side, we would have noticed an oblate ball, which contains over 150 billion stars. Our galaxy has dimensions that are hard to imagine. A ray of light travels from one side to the other for hundreds of thousands of Earth years! The center of our Galaxy is occupied by the core, from which huge spiral branches filled with stars extend. The distance from the Sun to the Galactic core is 30 thousand light years. The solar system is located on the outskirts of the Milky Way.
Stars in the Galaxy, despite the huge accumulation of cosmic bodies, are rare. For example, the distance between the nearest stars is tens of millions of times their diameters. This is not to say that the stars are scattered in the Universe chaotically. Their location depends on the forces of gravity that hold the celestial body in a certain plane. Star systems with their own gravitational fields are called galaxies. In addition to stars, the galaxy includes gas and interstellar dust.
Composition of galaxies.
The universe is also made up of many other galaxies. The closest to us are distant at a distance of 150 thousand light years. They can be seen in the sky of the southern hemisphere as small foggy specks. They were first described by Pigafett, a member of the Magellanic expedition around the world. They entered science under the name of the Large and Small Magellanic Clouds.
The closest galaxy to us is the Andromeda Nebula. It has a very large size, so it is visible from the Earth with ordinary binoculars, and in clear weather - even with the naked eye.
The very structure of the galaxy resembles a giant convex spiral in space. The solar system is located on one of the spiral arms ¾ of the distance from the center. Everything in the galaxy revolves around the central core and obeys the force of its gravity. In 1962, astronomer Edwin Hubble classified galaxies based on their shape. The scientist divided all galaxies into elliptical, spiral, irregular and barred galaxies.
There are billions of galaxies in the part of the Universe accessible for astronomical research. Taken together, astronomers call them the Metagalaxy.
Universe Galaxies
Galaxies are represented by large groups of stars, gas, dust, held together by gravity. They can vary significantly in shape and size. Most of the space objects belong to a galaxy. These are black holes, asteroids, stars with satellites and planets, nebulae, neutron satellites.
Most of the galaxies in the Universe contain vast amounts of invisible dark energy. Since the space between different galaxies is considered void, they are often called oases in the void of space. For example, a star named the Sun is one of the billions of stars in the Milky Way galaxy in our universe. At ¾ the distance from the center of this spiral is the solar system. In this galaxy, everything is constantly moving around the central core, which obeys its gravity. However, the nucleus also moves with the galaxy. Moreover, all galaxies move at super speeds.
Astronomer Edwin Hubble in 1962 conducted a logical classification of the galaxies in the Universe, taking into account their shape. Now galaxies are divided into 4 main groups: elliptical, spiral, bar (bridge) and irregular galaxies.
What is the largest galaxy in our universe?
The largest galaxy in the universe is a super-giant lenticular galaxy located in the Abell 2029 cluster.
Spiral galaxies
They are galaxies that resemble a flat spiral disk with a bright center (core). The Milky Way is a typical spiral galaxy. Spiral galaxies are usually named with the letter S, they are divided into 4 subgroups: Sa, Sо, Sc and Sb. Galaxies belonging to the Sо group are distinguished by light cores that do not have spiral arms. As for the Sa galaxies, they are distinguished by dense spiral arms tightly wrapped around the central core. The arms of Sc and Sb galaxies rarely surround the core.
Messier spiral galaxies
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Barred galaxies
Barred galaxies are similar to spiral galaxies, but they still have one difference. In such galaxies, spirals begin not from the core, but from the barriers. About 1/3 of all galaxies fall into this category. They are usually denoted by the letters SB. In turn, they are divided into 3 subgroups Sbc, SBb, SBa. The difference between these three groups is determined by the shape and length of the bridges, from where, in fact, the spiral arms begin.
Messier barred spiral galaxies
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Elliptical galaxies
The shape of galaxies can vary from perfectly round to elongated oval. Their distinguishing feature is the absence of a bright central core. They are designated by the letter E and are divided into 6 subgroups (in shape). Such forms are designated from E0 to E7. The former are almost round in shape, while the E7 is characterized by an extremely elongated shape.
Messier elliptical galaxies
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Wrong galaxies
They do not have any pronounced structure or shape. Irregular galaxies are usually divided into 2 classes: IO and Im. The most common is the Im class of galaxies (it has only a slight hint of structure). In some cases, spiral remains can be traced. IO belongs to a class of galaxies that are chaotic in shape. Small and Large Magellanic Clouds are a prime example of the Im class.
Irregular Messier galaxies
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Table of characteristics of the main types of galaxies
| Elliptical galaxy | Spiral galaxy | Wrong galaxy | |
| Spheroidal component | Whole galaxy | there is | Very weak |
| Star disk | No or mild | Main component | Main component |
| Gas and dust disk | Not | there is | there is |
| Spiral branches | No or only near the core | there is | Not |
| Active nuclei | Meet | Meet | not |
| Percentage of the total number of galaxies | 20% | 55% | 5% |
Large portrait of galaxies
Not so long ago, astronomers began working on a joint project to identify the location of galaxies throughout the universe. Their task is to get a more detailed picture of the general structure and shape of the Universe on a large scale. Unfortunately, the scale of the universe is difficult for many people to understand. Take, for example, our galaxy, which consists of more than a hundred billion stars. There are billions of galaxies in the universe. Discovered distant galaxies, but we see their light as it was almost 9 billion years ago (we are separated by such a great distance).
Astronomers have learned that most of the galaxies belong to a certain group (they began to call it a "cluster"). The Milky Way is part of a cluster that, in turn, is made up of forty known galaxies. As a rule, most of these clusters are part of an even larger grouping called superclusters.
Our cluster is part of a supercluster commonly referred to as the Virgo cluster. Such a massive cluster consists of more than 2 thousand galaxies. As astronomers mapped these galaxies, superclusters began to take on specific shapes. Large superclusters have gathered around what appear to be giant bubbles or voids. What kind of structure it is, no one knows yet. We do not understand what may be inside these voids. According to the assumption, they can be filled with a certain type of dark matter unknown to scientists, or have empty space inside. It will take a long time before we know the nature of such voids.
Galactic Computing
Edwin Hubble is the founder of galactic exploration. He is the first to figure out how the exact distance to the galaxy can be calculated. In his research, he relied on the method of pulsating stars, which are better known as Cepheids. The scientist was able to notice the connection between the period that is needed to complete one pulsation of brightness and the energy that the star gives off. The results of his research have become a major breakthrough in the field of galactic research. In addition, he found that there is a correlation between the red spectrum emitted by the galaxy and the distance to it (Hubble constant).
Nowadays, astronomers can measure the distance and speed of a galaxy by measuring the amount of redshift in the spectrum. It is known that all galaxies in the Universe move away from each other. The further the galaxy is from the Earth, the greater its speed of movement.
To visualize this theory, it is enough to imagine yourself driving a car that moves at a speed of 50 km per hour. In front of you, a car is going faster by 50 km per hour, which means that its speed is 100 km per hour. There is another car in front of him, which moves faster by another 50 km per hour. Despite the fact that the speed of all 3 cars will be different by 50 km per hour, the first car is actually moving 100 km per hour faster from you. Since the red spectrum indicates the speed of the galaxy moving away from us, the following is obtained: the greater the redshift, the faster the galaxy moves, and the greater its distance from us.
{!LANG-b8d63d8e1fd4bfad6216881bbab691af!}
{!LANG-8617d24d066d9bdf29e37d04e7903344!}
- {!LANG-fe54b146eab41f778a2139e5a4259fea!}
- {!LANG-06f0c9bf13e9bac1389a2ee744859952!}
- {!LANG-01d6747886cde7b5abda38055a19f3f7!}
- {!LANG-9390e124a6ddbcc2c9fb6e5be5ab7723!}
{!LANG-0900865c7bc9ea7b98cde0306d00a2a9!}
Astronomers also link most galaxies to specific groups called clusters. Our Milky Way belongs to a cluster of 40 explored galaxies. Such clusters are combined into large groups called superclusters. The cluster with our galaxy is part of the Virgo supercluster. This giant cluster contains more than 2 thousand galaxies. After scientists began to map the distribution of these galaxies, superclusters took on certain shapes. Most galactic superclusters were surrounded by giant voids. Nobody knows what might be inside these voids: space like interplanetary space or a new form of matter. It will take a long time to solve this riddle.
Interaction of galaxies
No less interesting for scientists is the question of the interaction of galaxies as components of space systems. It's no secret that space objects are in constant motion. Galaxies are no exception to this rule. Some of the types of galaxies could cause collisions or mergers of two cosmic systems. If you understand how these space objects appear, large-scale changes become more understandable as a result of their interaction. During the collision of two space systems, a huge amount of energy is released. The meeting of two galaxies in the vastness of the Universe is an even more likely event than a collision of two stars. The collision of galaxies does not always end in an explosion. A small space system can freely pass by its larger counterpart, changing only slightly its structure.
Thus, the formation of formations occurs, similar in appearance to elongated corridors. In their composition, stars and gas zones stand out, new stars are often formed. There are times when galaxies do not collide, but only slightly touch each other. However, even this interaction triggers a chain of irreversible processes that lead to huge changes in the structure of both galaxies.
What is the future of our galaxy?
As scientists suggest, it is possible that in the distant future the Milky Way will be able to absorb a tiny satellite system, which is located at a distance of 50 light years from us. Studies show that this satellite has a long life potential, but when it collides with a giant neighbor, it is likely to end its separate existence. Astronomers also predict a collision between the Milky Way and the Andromeda Nebula. Galaxies move towards each other at the speed of light. Until a probable collision, wait approximately three billion Earth years. However, whether it will actually be now is difficult to argue due to the lack of data on the motion of both space systems.
Description of galaxies onKvant. Space
The site portal will take you to the world of interesting and fascinating space. You will learn the nature of the construction of the Universe, get acquainted with the structure of the known large galaxies, their components. As we read articles about our galaxy, some of the phenomena that can be observed in the night sky become clearer to us.
All galaxies are at a great distance from Earth. Only three galaxies can be seen with the naked eye: the Large and Small Magellanic Clouds and the Andromeda Nebula. It is unrealistic to count all galaxies. Scientists estimate that their number is about 100 billion. The spatial arrangement of galaxies is uneven - one region can contain a huge number of them, in the second there will not be even a single small galaxy at all. Astronomers were unable to separate the image of galaxies from individual stars until the early 90s. At this time, there were about 30 galaxies with individual stars. All of them were assigned to the Local Group. In 1990, a majestic event in the development of astronomy as a science took place - the Hubble telescope was launched into Earth's orbit. It is this technique, as well as new ground-based 10-meter telescopes, that made it possible to see a significantly larger number of allowed galaxies.
Today, the "astronomical minds" of the world are racking their brains about the role of dark matter in the formation of galaxies, which manifests itself only in gravitational interaction. For example, in some large galaxies, it makes up about 90% of the total mass, while dwarf galaxies may not contain it at all.
Evolution of galaxies
Scientists believe that the emergence of galaxies is a natural stage in the evolution of the Universe, which took place under the influence of the forces of gravity. The formation of protoclusters in the primary matter began about 14 billion years ago. Further, under the influence of various dynamic processes, the selection of galactic groups took place. The abundance of forms of galaxies is explained by the variety of initial conditions in their formation.
The compression of the galaxy takes about 3 billion years. Over a given period of time, the gas cloud turns into a star system. Star formation occurs under the influence of the gravitational compression of gas clouds. After reaching a certain temperature and density in the center of the cloud, sufficient for the start of thermonuclear reactions, a new star is formed. Massive stars are formed from thermonuclear chemical elements that exceed helium in mass. These elements create a primary helium-hydrogen environment. During grandiose supernova explosions, elements heavier than iron are formed. It follows from this that the galaxy consists of two generations of stars. The first generation is the oldest stars, composed of helium, hydrogen, and very few heavy elements. Second-generation stars have a more prominent heavy element admixture, as they form from primordial gas enriched in heavy elements.
In modern astronomy, galaxies as cosmic structures have a separate place. The types of galaxies, the features of their interaction, similarities and differences are studied in detail, and a forecast of their future is made. This area contains many more incomprehensible things that require additional study. Modern science has solved many questions regarding the types of galaxy construction, but there are also many blank spots associated with the formation of these cosmic systems. The current pace of modernization of research technology, the development of new methodologies for the study of space bodies give hopes for a significant breakthrough in the future. One way or another, galaxies will always be at the center of scientific research. And this is based not only on human curiosity. Having received data on the patterns of development of space systems, we will be able to predict the future of our galaxy called the Milky Way.
The most interesting news, scientific, author's articles about the study of galaxies will be provided by the portal site. Here you can find breathtaking videos, high-quality images from satellites and telescopes that will impress you. Dive into the world of unknown space with us!
\u003e The closest galaxy to us
Which galaxy is closest to the Milky Way: spiral Andromeda, dwarf galaxy in Canis Major, distance, map of galaxies, exploration with photos.
It should be understood that our galaxy is not unique in terms of its formation. That is, there are many more similar ones, united into specific groups. The Milky Way is home to the Local Group (54 galaxies), which is part of. So we are not alone.
Many believe that the Andromeda galaxy is the closest, because they go through a collision and merger with the Milky Way. But if we speak more scientifically, then this is the closest representative of the spiral type. The fact is that the dwarf was discovered not so long ago, so it's time to reconsider your knowledge.
Which galaxy is the closest
Now the Canis Major Dwarf Galaxy is the closest galaxy to the Milky Way. It is distant 42,000 light years from the center and 25,000 light years from the system.
Characteristics of the nearest galaxy
It is believed to contain a billion stars, many of which have entered the red giant phase. Formed in the shape of an ellipse. In addition, a whole stellar thread flashes behind her. It is an intricate ring-like structure - the Unicorn Ring wrapped around three times.
During the study of the ring, this dwarf galaxy was discovered in Canis Major. It is assumed that she was "eaten". And globular clusters close to its center (NGC 1851, NGC 1904, NGC 2298, and NGC 2808) once belonged to a swallowed galaxy.
Examples of galactic mergers captured by the Hubble telescope
Discovery of the galaxy closest to Earth
Prior to that, it was believed that the first place in terms of proximity was the Dwarf Elliptical Galaxy (70,000 light years from Earth). This is closer than (180,000 years).
The Canis Major dwarf galaxy appeared for the first time in 2003. Astronomers scanned 70% of the sky with the All-Sky Survey and found approximately 5,700 celestial sources of infrared radiation. Infrared technology is incredibly important as red light is not blocked by gas and dust. Thus, it was possible to find many M-type giants in the constellation Canis Major. Some structures formed weak arcs.
The large number of M-type stars was the reason why the formation was found. Red dwarfs with low temperatures are inferior in brightness, so they cannot be noticed without the use of technology. But they are clearly visible in the infrared range.
The data fueled the notion that galaxies could grow by absorbing smaller neighbors. Thus, our Milky Way galaxy appeared, which continues to do this today. And since the former stars of the Dwarf Galaxy in Canis Major are now ours, we can say that it is located the closest.
The former prize-winner was found in 1994 (dwarf in Sagittarius). Among the nearest spiral ones is (M31), which is hurrying towards us with an acceleration of 110 km / s. In 4 billion light years, the merger will occur.
What awaits the nearest galaxy?
Now you know that the closest galaxy to the Milky Way is a dwarf galaxy in Canis Major. But what will happen to her? Scientists believe it will eventually be torn apart by the gravity of the Milky Way. It is noticeable that her main body has already been distorted and this does not stop. The accretion will end with the objects completely merging, transferring 1 billion stars to our galaxy to the 200-400 billion that passed earlier. So the short distance to the nearest galaxy played a cruel joke on it.
Big Encyclopedic Dictionary
Extragalactic nebulae or island universes, giant star systems that also contain interstellar gas and dust. The solar system is part of our Milky Way Galaxy. All outer space to the limits where they can penetrate ... ... Collier's Encyclopedia
Giant (up to hundreds of billions of stars) star systems; these include, in particular, our Galaxy. Galaxies are classified into elliptical (E), spiral (S) and irregular (Ir). The nearest galaxies are the Magellanic Clouds (Ir) and the nebula ... ... encyclopedic Dictionary
Giant star systems, similar to our star system Galaxy (see Galaxy), which includes the solar system. (The term "galaxies", in contrast to the term "Galaxy", is written with a lowercase letter.) The outdated name G. ... ...
Giant (up to hundreds of billions of stars) star systems; these include, in particular, our Galaxy. Galaxies are classified into elliptical (E), spiral (S) and irregular (Ir). The nearest galaxies are the Magellanic Clouds (Ir) and the nebula ... ... Astronomical Dictionary
Galaxies - giant stellar systems with the number of stars from tens to hundreds of billions in each. Modern estimates give about 150 million galaxies in the known Metagalaxy. Galaxies are subdivided into elliptical (designated in astronomy by the letter E), ... ... The beginnings of modern natural science
Giant (up to hundreds of billions of stars) star systems; these include, in particular, our Galaxy. G. are subdivided into elliptical. (E), spiral (S) and irregular (Ir). The nearest to us G. Magellanic Clouds (Ir) and the Andromeda nebula (S). G. ... ... Natural science. encyclopedic Dictionary
Whirlpool Galaxy (M51) and its companion NGC 5195. Photo of the Kitt Peak Observatory. Interacting galaxies are galaxies located in space close enough for mutual gravity to be significant in ... Wikipedia
Star systems that differ in shape from spiral and elliptical in chaos, clumpy. Sometimes there are N. of the city, without a clear form, amorphous. They consist of stars with an admixture of dust, while most N. g. ... ... Great Soviet Encyclopedia
- ... Wikipedia
Books
- Galaxies, Veta Sergeevna Avedisova, Vladimir Georgievich Surdin, Dmitry Zigfridovich Vibe. The fourth book in the series "Astronomy and Astrophysics" contains an overview of modern concepts of giant stellar systems - galaxies. It tells about the history of the discovery of galaxies, about their ...
- Galaxies, Surdin VG. The fourth book in the series "Astronomy and Astrophysics" contains an overview of modern concepts of giant stellar systems - galaxies. It tells about the history of the discovery of galaxies, about their ...
Andromeda is a galaxy also known as M31 and NGC224. It is a spiral formation located approximately 780 kp (2.5 million from Earth.
Andromeda is the galaxy closest to the Milky Way. It is named after the mythical princess of the same name. Observations of 2006 led to the conclusion that there are about a trillion stars here - at least twice as many as in the Milky Way, where there are about 200 - 400 billion. Scientists believe that the collision of the Milky Way and the Andromeda galaxy will happen in about 3, 75 billion years, and eventually a giant elliptical or disk galaxy will be formed. But more on that later. First, let's find out what a "mythical princess" looks like.
The figure shows Andromeda. The galaxy has blue and white stripes. They form rings around it and cover hot glowing giant stars. The dark blue-gray stripes contrast sharply against the backdrop of these bright rings and show areas where star formation is just beginning in dense cloud cocoons. When viewed in the visible part of the spectrum, the Andromeda rings look more like spiral arms. In the ultraviolet range, these formations are more like ring structures. They were previously detected by NASA's telescope. Astronomers believe that these rings indicate the formation of a galaxy as a result of a collision with a neighboring one more than 200 million years ago.
Moons of Andromeda
Like the Milky Way, Andromeda has a number of dwarf satellites, 14 of which have already been discovered. The most famous are M32 and M110. Of course, it is unlikely that the stars of each of the galaxies will collide with each other, since the distances between them are very large. Scientists have a rather vague idea of \u200b\u200bwhat will actually happen. But a name has already been invented for the future newborn. Milkomeda - this is how scientists call the unborn giant galaxy.
Colliding stars
Andromeda is a galaxy with 1 trillion stars (10 12) and the Milky Way 1 billion (3 * 10 11). However, the chance of collision of celestial bodies is negligible, since there is a huge distance between them. For example, the closest star to the Sun, Proxima Centauri, is 4.2 light years away (4 * 10 13 km), or 30 million (3 * 10 7) solar diameters. Imagine that our luminary is a table tennis ball. Then Proxima Centauri will look like a pea, located at a distance of 1100 km from it, and the Milky Way itself will stretch in breadth for 30 million km. Even the stars in the center of the galaxy (and this is where their largest cluster is) are located at intervals of 160 billion (1.6 * 10 11) km. It's like one table tennis ball for every 3.2 km. Therefore, the chance that any two stars will collide when galaxies merge is extremely small.
Collision of black holes
The Andromeda Galaxy and Milky Way have a central Sagittarius A (3.6 * 10 6 solar masses) and an object within the P2 cluster of the Galactic Core. These black holes will converge at a single point near the center of the newly formed galaxy, transferring orbital energy to stars, which will eventually shift to higher trajectories. The above process can take millions of years. When black holes get closer to within one light year of each other, they will start emitting gravitational waves. The orbital energy will become even more powerful until the fusion is complete. Based on data from simulations carried out in 2006, the Earth may first be thrown almost to the very center of the newly formed galaxy, then it will pass near one of the black holes and be ejected beyond Milkomeda.
Confirmation of the theory
The Andromeda Galaxy is approaching us at a speed of about 110 km per second. Until 2012, there was no way to know if a collision would occur or not. The Hubble Space Telescope helped scientists conclude that it is almost inevitable. After tracking the movements of Andromeda from 2002 to 2010, it was concluded that the collision would occur in about 4 billion years.
Similar phenomena are widespread in space. For example, Andromeda is believed to have interacted with at least one galaxy in the past. And some dwarf galaxies, such as SagDEG, continue to collide with the Milky Way, creating a single formation.
Research also suggests that M33, or the Galaxy of the Triangle, the third largest and brightest member of the Local Group, will also be participating in this event. Its most likely fate will be the entry into orbit of the object formed after the merger, and in the distant future - the final unification. However, the collision of M33 with the Milky Way before Andromeda approaches, or our Solar System will be thrown outside the Local Group, is excluded.
The fate of the solar system
Scientists from Harvard claim that the timing of the unification of galaxies will depend on the tangential speed of Andromeda. Based on the calculations, it was concluded that there is a 50% chance that during the merger the Solar System will be thrown at a distance three times the current distance to the center of the Milky Way. It is not known exactly how the Andromeda galaxy will behave. Planet Earth is also under threat. Scientists say about a 12% probability that some time after the collision we will be thrown outside our former "home". But this event, most likely, will not produce strong adverse effects on the Solar System, and celestial bodies will not be destroyed.
If we exclude planetary engineering, then by time the surface of the Earth will be very hot and there will be no water left on it in a liquid state, and therefore no life.
Possible side effects
When two spiral galaxies merge, the hydrogen present on their disks is compressed. An intensified formation of new stars begins. For example, this can be observed in the interacting galaxy NGC 4039, otherwise known as "Antennas". In the event of a merger between Andromeda and the Milky Way, it is believed that little gas will remain on their disks. Star formation will not be as intense, although the nucleation of a quasar is quite likely.
Merge result
The galaxy formed during the merger is tentatively called Milkomed by scientists. The simulation result shows that the resulting object will be elliptical. Its center will have a lower density of stars than modern elliptical galaxies. But a disc shape is also likely. Much will depend on how much gas remains within the Milky Way and Andromeda. In the near future, the rest will merge into one object, and this will mean the beginning of a new evolutionary stage.
Facts about Andromeda
- Andromeda is the largest galaxy in the Local Group. But probably not the most massive one. Scientists suggest that more is concentrated in the Milky Way and this is what makes our galaxy more massive.
- Scientists are exploring Andromeda in order to understand the origin and evolution of similar formations, because it is the closest spiral galaxy to us.
- Andromeda from Earth looks amazing. Many even manage to photograph her.
- Andromeda has a very dense galactic core. Not only are there huge stars at its center, but there is also at least one supermassive black hole tucked away at its core.
- Its spiral arms are curved as a result of gravitational interaction with two neighboring galaxies: M32 and M110.
- At least 450 globular star clusters revolve inside Andromeda. Among them are some of the densest that have been found.
- The Andromeda Galaxy is the most distant object that can be seen with the naked eye. You need a good vantage point and a minimum of bright light.
In conclusion, I would like to advise readers to often raise their gaze to the starry sky. It keeps a lot of new and unknown. Take some free time to watch space on the weekend. The Andromeda Galaxy in the sky is a must see.