According to the most popular cosmological paradigm, the greater part of the galaxy mass is accumulated in the dark matter halo. The mass value can be measured in terms of various model assumptions, analyzing the available observational data, for example, the distribution of the rotation velocity at large distances from the center (the rotation curve). It is much more difficult to make an estimate of the shape of the dark halo in a particular galaxy, i.e. to understand whether it is spherical, flattened or triaxial. More...

SAO researchers have discovered that supercritical accretion disks eject hot gas with a velocity of a few thousand kilometers per second. The supercritical regime of accretion onto black holes is very important for astrophysics. In the first half-billion years just after our Universe was born, supermassive black holes (quasars) began to appear and grow in centers of young galaxies. More...

A unique set of linear polarization measurements in the spectrum of the Seyfert galaxy Mkn 6 was obtained with the 6-meter telescope. It was shown for the first time that the analysis of the polarization angle dependence on the velocity across the hydrogen line profiles due to the gas emission in the broad-line formation region near the massive AGN allows to determine directly from observations the type of motion in the broad-line formation region, which in the case of Mkn 6 turned out to be Keplerian at distances less than 0.02 pc from the nucleus. The lower mass limit determined for the supermassive black hole in the center of the Mkn 6 galaxy is equal to 150 million solar masses. More...