In the broad sense of the word, the Universe are stars and a space. However stars are not randomly scattered in space, they are united in huge "чтхчфэ№х юё=Ёютр" or galaxies.
All stars which we see at the night, and the Sun belong to our galaxy known under the name the Galaxy, or the Milky Way. As the Milky Way also is called the pale silvery strip bent in the night sky. The Galaxy has the form of a disk with camber in the middle. This camber is called as a kernel. On the star chart it is in a direction of constellation of the Sagittarius, in the most dense part of the Milky Way. To glance in depth of a kernel it is impossible because of dense congestions of a star dust. In the disk of group of stars settle down along the bent branches, spirals departing from a kernel. Our Galaxy - one of numerous spiral galaxies in the Universe. As well as other galaxies, it rotates in a space.
By studying of an arrangement of stars and a direction of their movement astronomers managed to find out Galaxies some of spiral branches. By means of radio telescopes they trace hydrogen congestions in these branches. Three the nearest to the Earth are called: a branch of Orion, a branch of Perseja and a branch of the Sagittarius. More close to a kernel the branch of Kariny is located. Besides, there are bases to believe that there is one more branch, the Centaur. All of them have been named on constellations in which they can be observed.
the Size of the Galaxy
Speaking about the sizes of galaxies, it is necessary to notice that our Galaxy is slightly larger than an average. In it is an order of 100 000 million stars, and at width its size reaches about 100 000 light years. Diameter of the central camber makes about 15 000 light years, while a thickness of a disk - only 3000 light years.
The Sun is located in the Galaxy disk on a spiral of Orion, approximately in 30 000 light years from the center. Once to round the Galaxy, it is required 225 million years. This period is called as space year.
Just as stars form galaxies, galaxies form congestions. Our Galaxy is a part of a congestion under the name Local Group. Also our nearest galactic neighbours, Big and Small Magellanovy of the Cloud, small, the wrong form of a galaxy here enter. The well-known fog of Andromedy is included too into Local Group. It represents a helicoid galaxy hardly more ours.
The Processes occurring in a disk of the Galaxy and in its kernel, considerably differ from each other. The stars located in a disk, youngish. Here many is bright-blue and white-blue stars. Some have merged together and form open congestions, such as, for example, Galaxies, or Seven Sisters, in constellation of a Taurus. Between stars in a disk there are clouds of a dust and gas which are called as fogs. From these fogs stars are born. It is considered that almost the one tenth weights of all Galaxy it is necessary on a share of fogs.
Gas and dust Clouds also contain the matter which has scattered in space at rupture of huge dying stars and a birth supernov. The part of this matter consists of metals. Therefore the stars which are born in these clouds, contain particles of metals.
Thus, the typical star located in a disk, is the young and hot star containing a significant amount of various metals. In astronomy such stars are called as stars of a flat component.
In the Galaxy kernel
Stars, it is dense "эрёхы ¦Ёшх" the Galaxy kernel, belong basically to the category of old red giants. The majority of them were formed at space explosion during which time there was also a Galaxy, approximately 12 000 million years ago. Stars of a disk component are much younger: to the Sun, for example, all 5 000 million years.
Red giants of a kernel are called as stars of a spherical component. They were formed of hydrogen and helium fogs before heavy elements after explosion supernov there have got, therefore in them there are not enough metals.
Red giants also are and on some distance from spherical camber where they form an original spherical ring round all Galaxy. Here and there the curious formations consisting of hundreds thousand of such stars, under the form reminding a glove which are called as spherical congestions are scattered.
And 47 Tukana, it is possible to see Two brightest spherical congestions, Omegu of a Centaur with open years in Southern hemisphere. In total we know 200 spherical congestions.
Strangely enough, spherical congestions and other stars in a ring do not rotate together with other part of the Galaxy. They dvizhutsja on the orbits round the galactic center. It is considered that they till now dvizhutsja on those trajectories which have drawn at the moment of the birth simultaneously with the Galaxy.
Very powerful radio signals proceed From the heart of the Galaxy: their source is known under the name "Р=Ёхыхч +". The Same site radiates also X-rays. Astronomers believe that only the black hole is capable to develop such energy. It is considered that in the center of the majority of galaxies there are black holes.