starry sky since ancient times attracted people's views.The best minds of all nations have tried to understand our place in the universe, imagine and justify its device.Scientific progress has allowed to go in exploring the vast expanses of space from the romantic and religious constructs a logical structure theory based on numerous factual material.Now, every student has an idea of what it looks like our own Milky Way according to recent studies, who, why, and when he gave her such a poetic name, and what is its estimated future.
origin of the name
term "Milky Way galaxy" is, in fact, a tautology.Galactikos in roughly translated from Greek means "milk."So the inhabitants of the Peloponnese called cluster of stars in the night sky, attributing its origin fiery Hera: Goddess did not want to feed Heracles, illegitimate son of Zeus, and in anger splashed breast milk.Drops and formed a stellar track seen on clear nights.A century later, scientists discovered that the observed lights - only a tiny part of the existing celestial bodies.Space of the universe, which is our planet, and they gave the name of the Galaxy or Milky Way.After confirming the hypothesis of the existence of other similar groups in space first term began for them universal.
scientific knowledge about the structure of the universe, including the solar system, little is taken from the ancient Greeks.Understanding how our galaxy looks like, have evolved from a spherical universe of Aristotle to the modern theories in which there is space black holes and dark matter.
The fact that the Earth - an element of the Milky Way, imposes certain restrictions on those who are trying to figure out what kind of shape is our galaxy.For an unambiguous answer to this question requires a view from outside, and at a great distance from the object of observation.Now science is deprived of such an opportunity.A kind of substitute for the casual observer gets to collect data on the structure of the Galaxy and their correlation with the parameters of other space systems available for the study.
collected data allow to say with confidence that our galaxy has a disk shape with a bulge (bulge) in the middle and radiating from the center of the spiral arms.The latter contain the brightest star system.The diameter of the disc is more than 100 thousand light years.
Center of the Galaxy is hidden by interstellar dust, complicates the study of the system.To cope with the problem of helping methods of radio astronomy.Certain wavelengths easily overcome any obstacles and give a much desired image.Our galaxy, the data obtained has a heterogeneous structure.
Conventionally there are two related to each other elements: the halo and the disk itself.The first subsystem has the following characteristics:
- shape is a sphere;
- it is considered the center of the bulge;
- greatest concentration of stars in the halo characteristic of his midsection, approaching the edge density is greatly reduced;
- rotation of this zone of the galaxy rather slow;
- halo mainly found old stars with a relatively small mass;
- subsystem considerable space filled with dark matter.
Galactic disk density greatly exceeds the star halo.The sleeves are found even just young and emerging space objects.
Center and the core
«heart» of the Milky Way in the constellation of Sagittarius.Without studying it difficult to fully understand what our galaxy.The name "core" in scientific works or applies only to the central area with a diameter of a few parsecs, or includes a bulge and gas ring, considered the birthplace of stars.It will be used by the first version of the term.
In the center of the Milky Way could hardly penetrate the visible light: he is faced with a lot of space dust that hides what looks like our galaxy.Photos and images, taken at infrared wavelengths, astronomers greatly expand the knowledge about the core.
information about the features of the radiation in the central part of the Galaxy prompted scientists to think that the kernel is at the core of the black hole.Her mass of more than 2.5 million times the mass of the sun.Around this object, according to the researchers, it rotates another, but less impressive on the parameters, the black hole.Current knowledge about the features of the structure of the cosmos suggest that these objects are in the center of most galaxies.
Light and darkness
combined influence of black holes on the motion of the stars brings about changes in the way our galaxy looks like: it leads to specific changes in the orbits of celestial bodies uncharacteristic, for example, near the solar system.The study of these trajectories and the ratio of speed to distance from the center of the galaxy formed the basis is now actively developing the theory of dark matter.The nature of it is shrouded in mystery.The presence of dark matter, presumably constitute the overwhelming part of all matter in the universe, it is recorded only for the effects of gravity just on orbit.
If dispel all the cosmic dust that hides from us the core, eyes open amazing picture.Despite the concentration of dark matter, this part of the universe is full of light emitted by a huge number of stars.One unit of space they are hundreds of times larger than near the sun.Approximately ten billion of them form the galactic bar, also called the bridge is not quite the usual form.
Learning Center system in the long-range possible to obtain detailed infrared image.Our galaxy, as it turned out, in the core has a structure reminiscent of peanuts in the shell.This "nut" is the bridge, which includes more than 20 million red giant (bright, but less hot stars).From the end of the bar disperse the spiral arms of the Milky Way.
Work related to the discovery of "peanuts" in the center of the star system, not only to shed light on what our galaxy structure, but also help to understand how it developed.Initially, in the space of a normal disk space existed in which over time form a bridge.Under the influence of the internal processes of the bar changed its form and became a sound like a nut.
Our house is on the space map
active star formation takes place in the bridge, and the spiral arms possessed by our galaxy.The name they were given at the constellations, which were discovered areas of branches: the Perseus arm, the Swan, Centaurus, Sagittarius and Orion.Near the latter (at a distance of not less than 28 thousand light years from the nucleus) and is the solar system.This region has certain characteristics, according to experts, have made possible the emergence of life on Earth.
galaxy and our solar system rotate with it.Laws of motion of the individual components is not identical.Large numbers of stars sometimes enters into the spiral tap, then separated from them.Only the light, lying on the border corotation circle, do not make such "travel."These include the sun, protected from the powerful processes that are constantly occurring in the sleeves.Even a slight displacement would negate all the other benefits of organisms on our planet.
sky with diamonds
sun - just one of many similar bodies that are full of our galaxy.Stars, solitary or grouped, the total number exceeds the latest data 400 billion. The closest to us, Proxima Centauri, is part of a system of three stars with a little more distant Alpha Centauri A and Alpha Centauri B. The brightest point of the night sky, Sirius A, is inCanis Major.Its luminosity according to various sources more than 17-23 times in the sun.Sirius was not alone, he is accompanied by a satellite, bearing a similar name, but marked B.
Children often begin to get acquainted with how our galaxy looks like, with a search of the North Star in the sky, or Alpha Ursa Minor.It owes its popularity position above the North Pole of the Earth.Polar luminosity greatly exceeds Sirius (almost two thousand times brighter than the Sun), but it can not challenge the right of Alpha Canis Major the title of the most striking because of the distance from the earth (estimated at between 300 and 465 light years).
stars are not only the luminosity and distance from the observer.Each is attributed to a particular quantity (per unit taken appropriate setting of the sun), the degree of surface heating, color.
most impressive dimensions have supergiants.The biggest concentration of the substance in the unit volume of different neutron stars.The color characteristic is inextricably linked to temperature:
- red coldest;
- heating of the surface to 6 000º, like the sun, generates a yellow tint;
- white and blue light has a temperature of more than 10 000º.
luminosity of the star can vary and reach a maximum shortly before its collapse.Supernova explosions are making a huge contribution to understanding how our galaxy looks like.Photos of the process, received telescopes hit.
collected based on these data have helped to restore the process that led to the outbreak, and to predict the fate of a number of cosmic bodies.
future Milky Way
Our galaxy and other galaxies are constantly in motion and interact.Astronomers have discovered that the Milky Way has repeatedly absorbed neighbors.Similar processes are expected in the future.Over time, it will include Magellanic Cloud and a number of dwarf systems.The most impressive event is expected in 3-5 billion years.It will be a collision with Andromeda, the only neighbor that is visible from Earth with the naked eye.As a result, the Milky Way would be the elliptical galaxy.
endless expanses of space dazzling.It is frustrating to realize the enormity of hard not only the Milky Way or the whole universe, and even the Earth.However, thanks to advances in science, we can imagine at least some part of the world are tremendous.