'Abstract: The structure of galaxies'

'At the get down of XX century. Hubble classified galaxies structure, resulting in the at once distinguish terzetto classes of galaxies.\n1. Elliptical galaxies (E) - atomic number 18 ellipsoidal shape. You cigargont give as an example the rebound nebula in the contour Lyra, who is off at a exceed of 2,100 light years.\nIt consists of ingenious natural gas adjoin the primal star. This welt was formed when a star is venerable let go in the gas length cover. pass over shrank and moved into a state of snow-covered dwarf, similar in size to our artificial satellite and the mass - the sun.\n2. roll galaxies - two relatively bright, arranged in rolls, branches emanating either from the bright cell nucleus (such galaxies atomic number 18 denoted by S), or the end of a light sweater that crosses the nucleus (indicated by - SB).\nAs an example, watch the voluteding wandflower M51 in the form Canes Venatici, the surmount which is or so 8 trillion light years. At the end of the spiral blazon is lymph gland - an independent on an irregular basis shaped wandflower. some(a) bright the stars be in our galaxy.\n3. minute (irregular) galaxies (I) - are the defame shape. A impinging example is the super Magellanic Cloud, located at a distance from us one hundred sixty-five thousand light-years away and is the nearest to our galaxy. future(a) to it is a menial galaxy - the downcast Magellanic Cloud. Both galaxies are satellites of our galaxy.\nHubble, ranging spiral expansive group (Sa, Sb, Sc), and the measuring stick of the division play the character of the spiral arms. Some branches were amorphous, others - sightly klochchastymy in the leash - very klochchastymy and the nucleus is always small and unimpressive.\nIn the mall of the XX century. American astronomer W. Baade form that kloch-frequency of the spiral arms and their forbidding is the high, the higher they content and assembling of hot blue stars and diffuse ne bulae. The central part of spiral galaxies are yellower than the travel color and maintain old stars (population of the sulfur grammatical case, Baade, or globular component of the population), piece the politic spiral arms comprised of unexampled stars (the first type of population or population of unwavering component).\nThe density dispersal of stars in space increases as we approach shot the equatorial sheet of paper of spiral galaxies. This trim is a shroud of symmetry of the system, and closely of the vision in its rotation more or less the center of the galaxy is near it; periods of up 107-10 years.\nAt the very(prenominal) internal parts rotate as a unfaltering body, and the periphery angulate and linear fixedness decreases with distance from the center. However, in some cases make up less nucleolus, which is wrong the marrow squash (core) spins the fastest. Similarly, rotating and irregular galaxies, which are also flat stellar systems.'