The divisity of galaxies.

The galaxies are the giant (to hundred of billions of stars) star systems, where the stars are connected by gravitation laws with each other. Take for instance our Galaxy. The galaxies are divided into elliptic (E); spiral (S) and irragular (Ir). The nearest to us galaxies are Magellan's clouds (Ir) and Andromeda nebula (S). The galaxies formed congestions.

Spiral galaxies.

Spiral galaxies (S) present one of the main type of galaxies (50% from all the majority). Their mass is 10^12 МD. Each spiral galaxy has a core a flat disk where the spiral brancher locate. The stars and interstellar substance of spiral galaxies rotate around the core.

Galaxies with an active cores.

In every galaxy, besides the largest galaxies, a central part is stand out. This is a core. In normal galaxies, such as our Galaxy, the great brightness of the core is accounted for the high concentration of stars.

There are galaxies with especially bright cores. In such galaxies we can watch a bright source looks like a star and a luminous gas which moves on a great speed - thousands of kilometers in a second. Galaxies with an active cores were found out by Carl Seyfert in 1943 and later got the name of seyfertous galaxies. Today we know thousands of such ojects.

The intarective galaxies.

Different statiatic investigations foun out that the majority of the interactive galaxies have met not sudenly but they are relatives, connected by one and the same parentage. They are aproaching to each other and then moving away.