Spiral galaxies are flattened stellar systems with Central nearly spherical nucleus, have two or more frequently ragged spiral branches. In spiral branches of the galaxy are concentrated their brightest young stars, glowing nebula (regions of ionized hydrogen), young clusters and associations of stars. That is why the spiral pattern is clearly seen in very remote galaxies, although the share of spiral branches represent no more than a few percent of the total mass of each galaxy. The bulk of the stars of the S-galaxies form "solid" drive. Part of the galactic nucleus consists of stars and gas. At the core lies about hundredth of a whole mass of the galaxy. Some galaxies primary energy release occurs in the nucleus. C. A. Ambartsumyan called this phenomenon activity of galactic nuclei.

The giant spiral galaxies with active nuclei has been called Seyfert. Their systematic study began in 1943 K. Seifert (USA). He found in the spectra of these galaxies very broad emission lines of hydrogen, helium, ionised iron. Usually in galaxies emission lines belong gas ionized radiation from hot stars of spectral classes O, In (zone ionized hydrogen), and the stars Of That Century, the width of lines corresponds to the velocity of the stars. These speeds of 200 km/S. the Line, which found Seifert, had a width corresponding to several thousand km/s is Now known very wide line Seyfert galaxies, corresponding to speeds of up to 30 000 km/S. it is Interesting that a broad line Seyfert galaxies belong to the allowed transitions in atoms and ions, i.e., they are formed in dense gas. In a typical areas of ionized hydrogen are observed forbidden lines. This difference is due to different density of the gas. In very sparse clouds excited States of electrons having a great time living there long as the electron spontaneously go into a lower energy state and will not be emitted a quantum of light. In the dense clouds of atoms and ions collide quite often, so the electron energy in the excited state transitions in collisions in the kinetic energy of colliding particles. This energy does not have time will be displayed in the quanta of radiation. In the dense clouds of possible radiation only allowed lines that match excited States with very little life time, less than the time between collisions of particles.

The big width allowed lines in the spectra of Seyfert galaxies complies with great speed dense clouds. In the spectra of these galaxies are observed and forbidden lines, the width of which corresponds to a speed of 500 km/S. In the banned lines Shine sulfur, nitrogen, oxygen, neon, iron, and meet the lines are very high degree of ionization.

Nuclei of Seyfert galaxies are powerful sources of radiation from radio to x-ray ranges. Full luminosity kernel significantly exceeds the total luminosity of the hundreds of billions of stars throughout the galaxy. For example, optical luminosity of the nucleus of NGC 1068 is 5•108LСолнца and infrared 1011LСолнца, stellar luminosity of the galaxy is about 5•1010LСолнца.

The spectrum of radiation of the nuclei is determined by the thermal emission from a hot plasma, synchrotron radiation, the inverse Compton-effect. The main generator of energy in nuclei is a most likely a giant black hole (mass about Ana). The processes taking place in the vicinity of such holes, according to the estimates, in principle, can provide the energy of the nuclei of Seyfert galaxies.

The galaxies with active nuclei are blue galaxies B. E. Margaryan (more than 500 objects of different morphological types). In the works of M. A. Arakelyan and E. A. Diba analyzed two models that explain the abnormally blue galaxies Margaryan: intensive formation and activity of nuclei of these elliptical galaxies.