Milky Way

A white stripe in the night sky, especially visible in the dark without the moon at night. This is because the autumn evenings run across the sky from northeast to southwest, i.e. roughly coincides with the departure of migratory birds. According to written sources, the first attempt was made to scientifically explain the Bird's Path in ancient Greece. What is actually the Milky Way, the first to understand Pythagoras in the VI century. pr. Kr. He insisted that it was a pool of many weak stars whose eyes could not be seen in isolation. G. Galilee convinced him, looking at the Milky Way through his invented telescope.

The Milky Way is a projection of a giant star system in the sky, as demonstrated by the English astronomer William Hitchel in the 18th century, relying on the stars' calculations in various directions of the sky. The first true model of this star system was created only in the twentieth century. early in the year. The galaxy consists of hundreds of billions of stars, their swarms, interstellar gases, and dust clouds called the Shadows. Similar galaxies spread in all directions from it are numerous. So this galaxy is no different in the universe. We will continue to call the Galaxy of the Milky Way galaxy.

The sun is running around the planet with its planets around the Galactic Center in the direction of Sagittarius constellation and away from us at 28,000. The stars of the galaxy are the most densely clustered part of the disc-shaped space. The diameter of this disc is about 100,000. Because the Sun is inside it, the other distant disc stars come together in a glowing circle - the Bird Path that divides the sphere of the sky into two approximately equal parts. If the stars on the Galaxy were of the same density and if the interstellar space were transparent, the Bird Trail would look like a middle-lined strip. However, the density of stars is uneven, and there are clouds of light-absorbing dust in the interstellar space. As a result, the Bird's Trail looks like a bright strip of very irregular contours, narrowing, widening or splitting into several furrows.

The Bird's Trail is the narrowest and shimmers in the winter and spring when it travels through the constellations of the Great Dog, Unicorn, Twins, Carrier, Persia, Casasopia and Cefee. The part of the Milky Way that is visible in summer and autumn is much brighter. The Swan Constellation The Bird Trail's continuous band breaks down into two furrows. One of them flickering through the corners of the constellations of Lapps and Hercules and disappears at the constellation of the Snake Head. The second gang extends through the constellations of Strule, Eagle, Shield and finds himself in the constellation of Sagittarius. Further to the south, the Paukščių Takas part of the geographical latitude of Lithuania is not visible. In the southern hemisphere, it extends from the Great Dog and through Laagagal, Sail, Kilio, Centaurus, Cross, Campain, Scorpio's constellations are coming closer to Sagittarius on the other side.

The Sagittarius constellation The Bird Trail is the widest and brightest, there is the Galactic Center. In the opposite direction, its direction is called the anticenter and lies at the boundary of the Carrier and Taurus constellations. Approximately in the middle of the Milky Way is the galaxy halfway, from which galaxy width b is counted in both directions: it equals 0o on the equator, the north and south pole of the galaxy (the first - the constellation of Berenicus, the second - the constellation of Sculptor) + 90o and - 90o. The Galactic Length l is measured by the arc along the Galactic Equator from the direction of the Galactic Center to the West East from 0o to 360o.


Structure of the galaxy:

The galactic disc is just one of the two components of the galactic. It is surrounded on all sides by a smaller density spheroid with a diameter much larger than the disc. The radius of the latter is about 50,000, and the spheroid is about 80,000. The spheroid is slightly flattened - its pendulum radius is equal to a radius of 0.8 in the plane of the disc. The disc and spheroid centers overlap. The density of disc stars increases as it approaches its plane, and the density of spheroid stars is approaching the center of the galaxy. The disc is thickening towards the center. In this way, a central star body with a radius of about 8,000 is formed around the Galactic Center. In it, the stars are denser times more than the sun. Their orbit is an elongated ellipse, tilted at a wide angle to the disc plane. It is believed that the Galactic Center has a black abyss with a mass of about 5 · 106 M. It is surrounded by a few light-years of hot rotating hot plasma spin.
There are about 250 billion stars in the Galaxy, 90% of them on disk, 5% on spheroids and 5% on central. There are still gas and dust clouds in the galaxy disk and in the central pool, which make up 1/50 of the total mass of the stars.

The stars and nebulae that make up the galactic disk run around the center of the galactic orbit in orbit. The distance between each star and the nebula from the center is equivalent to a certain orbital speed. If the speed of the run would be just proportional to the distance, then the Galaxy would turn like a solid body like a gramophone plate. However, this is not the case - the dependence of its rotation speed on the center distance is difficult. With a solar distance from the center of the galactic center (28,000), the speed is 220 km / s, so it turns once around the center at over 230 million. years. Almost all of the stars in the galactic disc have a chemical composition similar to that of the Sun.

Our Galaxy is a spiral system. Its disk has large masses of hot stars, supermillas, and gas and dust clouds in spiral-shaped wires. Smaller mass stars spread across the disc. The sun is in the so-called Orion Spiral. The closest to the center of the galaxy is the Sagittarius's viola, and on the anticentre's side - the vie.

The stars of the galactic spheroid also fly around its center, but each one individually. Their orbits, mostly very elongated ellipses, form a wide range of angles with the plane of the disc (like the stars of the central body).

The closest to the center are the spheroidal orbit points - the perpendiculars - somewhere in the central reservoir, and the farthest - the apogalts - on the edges of the galaxy. These stars are around the center around 100 million. years. The galaxy's spheroidal crumb masses are smaller than the Sun's mass, and their outer layers have heavy elements between 100 and 1000 times less than the disc stars.

In addition to single stars, the spheroid and the central reservoir contain a few hundred spherical stars.

The galactic spheroid is surrounded by a galactic crown on all sides, with a radius of 700,000. There are almost no single stars in the crown, only a few spherical spheres and invisible material, the thrust of which affects the movement of the stars of the Galactic. The mass of this invisible material is at least 10 times the total mass of all galactic stars.

The mass of galaxy stars and interstellar matter is about 2 · 1011 M, and along with the invisible material - 2 · 1012 M.