What is the distance to the nearest galaxy? March 12th, 2013
For the first time, scientists have been able to measure the exact distance to our nearest galaxy. This dwarf galaxy known as Large Magellanic Cloud. It is located at a distance of 163 thousand light years from us, or 49.97 kiloparsecs, to be precise.
The Large Magellanic Cloud galaxy slowly floats through space, bypassing our galaxy Milky Way around just as the Moon revolves around the Earth.
Huge clouds of gas in the region of the galaxy are slowly dissipating, resulting in the formation of new stars that illuminate with their light interstellar space, creating bright colorful space landscapes. I was able to capture these landscapes in photographs space telescope "Hubble".
The shallow galaxy Large Magellanic Cloud includes the Tarantula Nebula - the brightest stellar nursery in space in our neighborhood - and has shown signs of new star formation.
Scientists were able to make the calculations by observing rare close pairs of stars known as eclipsing double stars. These pairs of stars are gravitationally bound to each other, and when one star eclipses the other, as seen by an observer on Earth, the overall brightness of the system decreases.
If you compare the brightness of stars, you can calculate the exact distance to them with incredible accuracy.
Determining the exact distance to space objects very important for understanding the size and age of our Universe. For now, the question remains open: none of the scientists can say for sure what the size of our Universe is yet.
Once astronomers have achieved such precision in determining distances in space, they will be able to look at more distant objects and, ultimately, be able to calculate the size of the Universe.
Also, new capabilities will make it possible to more accurately determine the expansion rate of our Universe, as well as more accurately calculate Hubble constant. This coefficient was named after Edwin P. Hubble, an American astronomer who proved in 1929 that our Universe has been constantly expanding since its beginning.
Distance between galaxies
The Large Magellanic Cloud Galaxy is the closest dwarf galaxy to us, but a large galaxy is considered our neighbor spiral galaxy Andromeda, which is located at a distance of about 2.52 million light years from us.
The distance between our galaxy and the Andromeda galaxy is gradually decreasing. They are approaching each other at a speed of approximately 100-140 kilometers per second, although they will not meet very soon, or rather, in 3-4 billion years.
Perhaps this is what the night sky will look like to an observer on Earth in a few billion years.
The distances between galaxies can thus be very different. different stages time, since they are constantly in dynamics.
Scale of the Universe
The visible Universe has an incredible diameter, which is billions, and maybe tens of billions of light years. Many objects that we can see with telescopes no longer exist or look completely different because the light took an incredibly long time to reach them.
The proposed series of illustrations will help you imagine at least general outline the scale of our Universe.
Solar system with its largest objects(planets and dwarf planets)
The Sun (in the center) and the stars closest to it
The Milky Way Galaxy, showing the group of star systems closest to the Solar System
Group nearest galaxies, which includes more than 50 galaxies, the number of which is constantly increasing as new ones are discovered.
Local supercluster of galaxies (Virgo Supercluster). Size - about 200 million light years
Group of superclusters of galaxies
Visible Universe
Andromeda is a galaxy also known as M31 and NGC224. This is a spiral formation located at a distance of 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 in 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 picture shows Andromeda. The galaxy has white and blue stripes. They form rings around it and cover the hot giant stars. The dark blue-gray bands contrast sharply with these bright rings and show areas where star formation is just beginning in dense cloud cocoons. When observed in the visible part of the spectrum, Andromeda's rings look more like spiral arms. In the ultraviolet range, these formations are more like ring structures. They were previously discovered by a NASA 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 galaxy will collide with each other, since the distances between them are very large. Scientists still have rather vague ideas about what will actually happen. But a name has already been invented for the future newborn. Mammoth - this is what scientists call the unborn giant galaxy.
Star collisions
Andromeda is a galaxy with 1 trillion stars (10 12), and the Milky Way - 1 billion (3 * 10 11). However, the chance of a collision between 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) the diameter of the Sun. 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 extend 30 million km in width. Even the stars in the center of the galaxy (which is where they are largest cluster) are located at intervals of 160 billion (1.6 * 10 11) km. That's like one table tennis ball for every 3.2 km. Therefore, the chance that any two stars will collide during a galaxy merger is extremely small.
Black hole collision
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 near the center of the newly formed galaxy, transferring orbital energy to the stars, which will eventually move to higher trajectories. The above process can take millions of years. When black holes come within one light years from each other, they will begin to emit gravitational waves. The orbital energy will become even more powerful until the merger is complete. Based on modeling data carried out in 2006, the Earth may first be thrown almost to the very center of the newly formed galaxy, then pass near one of the black holes and be ejected beyond the Milky Way.
Confirmation of the theory
The Andromeda Galaxy is approaching us at a speed of approximately 110 km per second. Up until 2012, there was no way to know whether a collision would occur or not. The Hubble Space Telescope helped scientists conclude that it was almost inevitable. After tracking the movements of Andromeda from 2002 to 2010, it was concluded that the collision will 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 Milky Way, creating a unified education.
Research also shows that M33, or the Triangulum Galaxy, is the third largest and most bright representative The local group will also participate in this event. Its most likely fate will be the entry into orbit of an object formed after the merger, and in the distant future - final unification. However, a collision of M33 with the Milky Way before Andromeda approaches, or our Solar System is thrown out of the Local Group, is excluded.
Fate of the Solar System
Scientists from Harvard claim that the timing of the galaxy merger will depend on the tangential speed of Andromeda. Based on the calculations, we concluded that there is a 50% chance that during the merger the Solar System will be thrown back to 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 there is a 12% chance that some time after the collision we will be thrown outside our former “home”. But this event will most likely not have major adverse effects on the Solar System, and celestial bodies will not be destroyed.
If we exclude planetary engineering, then by the time the Earth’s surface will become very hot and there will be no water left on it. liquid state, and therefore life.
Possible side effects
When two spiral galaxies merge, the hydrogen present in their disks is compressed. The intensive formation of new stars begins. For example, this can be observed in the interacting galaxy NGC 4039, otherwise known as the Antennae Galaxy. If Andromeda and the Milky Way merge, it is believed that there will be little gas left on their disks. Star formation will not be as intense, although the birth of a quasar is likely.
Merger result
Scientists tentatively call the galaxy formed during the merger Milcomeda. The simulation result shows that the resulting object will have an elliptical shape. Its center will have a lower density of stars than modern elliptical galaxies. But a disk form is also possible. Much will depend on how much gas remains within the Milky Way and Andromeda. In the near future, the remaining ones will merge into one object, and this will mark the beginning of a new evolutionary stage.
Facts about Andromeda
- Andromeda is the largest Galaxy in Local group. But probably not the most massive. Scientists suggest that there is more 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 formations similar to it, because it is the closest spiral galaxy to us.
- Andromeda looks amazing from Earth. Many even manage to photograph her.
- Andromeda has a very dense galactic core. Not only are huge stars located at its center, but there is also at least one supermassive black hole hidden at its core.
- Its spiral arms were twisted as a result gravitational interaction with two neighboring galaxies: M32 and M110.
- There are at least 450 globular star clusters orbiting inside Andromeda. Among them are some of the densest that have been discovered.
- The Andromeda Galaxy is the most distant object you can see naked eye. You will need good point visibility and a minimum of bright light.
In conclusion, I would like to advise readers to look up at the starry sky more often. It stores a lot of new and unknown things. Find some free time to observe space on the weekend. The Andromeda Galaxy in the sky is a sight to behold.
The science
Scientists were able to measure the exact distance for the first time to our nearest galaxy. This dwarf galaxy is known as Large Magellanic Cloud. She is located at a distance from us 163 thousand light years or 49.97 kiloparsecs to be exact.
The Large Magellanic Cloud galaxy slowly floats through space, bypassing our galaxy Milky Way around like The moon revolves around the earth.
Huge clouds of gas in the region of the galaxy slowly dissipate, resulting in the formation of new stars, which illuminate interstellar space with their light, creating bright colorful cosmic landscapes. A space telescope was able to capture these landscapes in photographs. "Hubble".
The shallow galaxy Large Magellanic Cloud includes Tarantula Nebula- the brightest stellar cradle in space in our neighborhood - they were seen in it signs of new star formation.
Scientists were able to make the calculations by observing rare close pairs of stars known as eclipsing double stars. These pairs of stars are gravitationally connected to each other, and when one star eclipses the other, as seen by an observer on Earth, the overall brightness of the system decreases.
If you compare the brightness of stars, you can calculate the exact distance to them with incredible accuracy.
Determining the exact distance to space objects is very important for understanding the size and age of our Universe. For now the question remains open: what is the size of our Universe None of the scientists can say for sure yet.
After astronomers managed to achieve such accuracy in determining distances in space, they will be able to deal with more distant objects and ultimately be able to calculate the size of the Universe.
Also, new capabilities will make it possible to more accurately determine the expansion rate of our Universe, as well as more accurately calculate Hubble constant. This coefficient was named after Edwin P. Hubble, an American astronomer who in 1929 proved that our The universe has been constantly expanding since the beginning of its existence.
Distance between galaxies
Galaxy Large Magellanic Cloud - closest to us dwarf galaxy, but a large galaxy - our neighbor is considered Andromeda spiral galaxy, which is located at a distance of approximately 2.52 million light years.
Distance between our galaxy and the Andromeda galaxy gradually decreasing. They approach each other at a speed of approximately 100-140 kilometers per second, although they will not meet very soon, or rather, after 3-4 billion years.
Perhaps this is what the night sky will look like to an observer on Earth in a few billion years.
The distances between galaxies are thus can be very different at different stages of time, since they are constantly in dynamics.
Scale of the Universe
The visible universe has incredible diameter, which is billions or maybe tens of billions of light years. Many objects that we can see with telescopes no longer exist or look completely different because the light took an incredibly long time to reach them.
The proposed series of illustrations will help you imagine at least in general terms the scale of our Universe.
The solar system with its largest objects (planets and dwarf planets)
The Sun (in the center) and the stars closest to it
The Milky Way Galaxy, showing the group of star systems closest to the Solar System
A group of nearby galaxies, including more than 50 galaxies, the number of which is constantly increasing as new ones are discovered.
Local supercluster of galaxies (Virgo Supercluster). Size: about 200 million light years
Group of superclusters of galaxies
Visible Universe
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 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 divided into elliptical (E), spiral (S) and irregular (Ir). The closest galaxies to us 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 lowercase letter.) Outdated name G.... ...
Giant (up to hundreds of billions of stars) star systems; These include, in particular, our Galaxy. Galaxies are divided into elliptical (E), spiral (S) and irregular (Ir). The closest galaxies to us are the Magellanic Clouds (Ir) and the nebula... ... Astronomical Dictionary
Galaxies- giant star systems with the number of stars from tens to hundreds of billions each. Modern estimates give about 150 million galaxies in the Metagalaxy known to us. Galaxies are divided into elliptical (denoted 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 divided into elliptical. (E), spiral (S) and irregular (Ir). The closest to us are the G. Magellanic Clouds (Ir) and the Andromeda Nebula (S). G.… … Natural science. encyclopedic Dictionary
The Whirlpool Galaxy (M51) and its satellite NGC 5195. Photograph of the Kitt Peak Observatory. Interacting galaxies are galaxies located close enough in space that mutual gravity is significantly ... Wikipedia
Stellar systems that differ in shape from spiral and elliptical ones by being chaotic and ragged. Sometimes there are N. g., which do not have a clear shape, are amorphous. They consist of stars mixed with dust, while most N. g.... ... Big Soviet encyclopedia
- ... Wikipedia
Books
- Galaxies, Avedisova Veta Sergeevna, Surdin Vladimir Georgievich, Vibe Dmitry Zigfridovich. The fourth book in the "Astronomy and Astrophysics" series contains an overview modern ideas about giant star systems - galaxies. It tells about the history of the discovery of galaxies, about their...
- Galaxies, Surdin V.G.. The fourth book in the series “Astronomy and Astrophysics” contains an overview of modern ideas about giant star systems - galaxies. It tells about the history of the discovery of galaxies, about their...
By understanding how and when galaxies, stars and planets could have appeared, scientists are closer to solving one of the main mysteries of the Universe. they claim that as a result big bang- and, as we already know, it occurred 15-20 billion years ago (see “Science and Life” No.) - exactly the kind of material arose from which celestial bodies and their clusters could subsequently be formed.
Planetary gas nebula Ring in the constellation Lyra.
The Crab Nebula in the constellation Taurus.
Great Nebula Orion.
The Pleiades star cluster in the constellation Taurus.
The Andromeda nebula is one of the closest neighbors of our Galaxy.
Satellites of our Galaxy - galaxy clusters stars: Small (top) and Large Magellanic Clouds.
An elliptical galaxy in the constellation Centaurus with a wide dust lane. It is sometimes called the Cigar.
One of the largest spiral galaxies visible from Earth through powerful telescopes.
Science and life // Illustrations
Our Galaxy - the Milky Way - has billions of stars, and they all move around its center. It's not just the stars that spin in this huge galactic carousel. There are also foggy spots, or nebulae. Not many of them are visible to the naked eye. It's a different matter if we consider starry sky through binoculars or a telescope. What kind of cosmic fog will we see? Distant small groups of stars that cannot be seen individually, or something completely, completely different?
Today, astronomers know what a particular nebula is. It turned out that they are completely different. There are nebulae consisting of gas, they are illuminated by stars. They often happen round shape, for which they received the name planetary. Many of these nebulae were formed as a result of the evolution of aged massive stars. An example of a “foggy remnant” of a supernova (we’ll tell you what it is later) is the Crab Nebula in the constellation Taurus. This crab-shaped nebula is quite young. It is known for sure that she was born in 1054. There are nebulae that are much older, their age is tens and hundreds of thousands of years.
Planetary nebulae and remnants of once flared supernovas could be called monument nebulae. But other nebulae are also known, in which stars do not go out, but, on the contrary, are born and grow. Such, for example, is the nebula that is visible in the constellation Orion, it is called the Great Orion Nebula.
Nebulae, which are clusters of stars, turned out to be completely different from them. The Pleiades cluster is clearly visible to the naked eye in the constellation Taurus. Looking at it, it is difficult to imagine that this is not a cloud of gas, but hundreds and thousands of stars. There are also “richer” clusters of hundreds of thousands, or even millions of stars! Such stellar “balls” are called spherical. star clusters. A whole retinue of such “tangles” surrounds the Milky Way.
Most of the star clusters and nebulae visible from Earth, although they are very far from us long distances, but still belong to our Galaxy. Meanwhile, there are very distant nebulous spots that turned out to be not star clusters or nebulae, but entire galaxies!
Our most famous galactic neighbor is the Andromeda nebula in the constellation Andromeda. When viewed with the naked eye, it appears as a hazy blur. And in photographs taken with large telescopes, the Andromeda nebula appears as a beautiful galaxy. Through a telescope, we see not only the many stars that make it up, but also the stellar branches emerging from the center, which are called “spirals” or “sleeves.” In size, our neighbor is even larger than the Milky Way, its diameter is about 130 thousand light years.
The Andromeda Nebula is the closest and largest known spiral galaxy. The beam of light goes from it to the Earth “only” about two million light years. So, if we wanted to greet the “Andromedans” by honking at them with a bright spotlight, they would find out about our efforts almost two million years later! And the answer from them would come to us after the same time, that is, back and forth - approximately four million years. This example helps to imagine how far the Andromeda nebula is from our planet.
In photographs of the Andromeda nebula, not only the galaxy itself, but also some of its satellites are clearly visible. Of course, the satellites of the galaxy are not at all the same as, for example, the planets - satellites of the Sun or the Moon - a satellite of the Earth. Satellites of galaxies are also galaxies, only “small” ones, consisting of millions of stars.
Our Galaxy also has satellites. There are several dozen of them, and two of them are visible to the naked eye in the sky Southern Hemisphere Earth. Europeans first saw them during trip around the world Magellan. They thought they were some kind of clouds and named them the Large Magellanic Cloud and the Small Magellanic Cloud.
The satellites of our Galaxy are, of course, closer to Earth than the Andromeda nebula. Light from the Large Magellanic Cloud reaches us in just 170 thousand years. Until recently, this galaxy was considered the closest satellite of the Milky Way. But recently, astronomers have discovered satellites that are closer, although they are much smaller than the Magellanic Clouds and are not visible to the naked eye.
Looking at the “portraits” of some galaxies, astronomers discovered that among them there are ones that are unlike the Milky Way in structure and shape. There are also many such galaxies - these are both beautiful galaxies and completely shapeless galaxies, similar, for example, to the Magellanic Clouds.
Less than a hundred years have passed since astronomers made an amazing discovery: distant galaxies scattering from one another in all directions. To understand how this happens, you can use balloon and do the simplest experiment with it.
Using ink, a felt-tip pen, or paint, draw small circles or squiggles to represent galaxies on the ball. As you begin to inflate the balloon, the drawn “galaxies” will move further and further away from each other. This is what happens in the Universe.
Galaxies rush, stars are born, live and die in them. And not only stars, but also planets, because in the Universe there are probably many star systems, similar and dissimilar to ours solar system, born in our Galaxy. IN Lately Astronomers have already discovered about 300 planets orbiting other stars.