Artistic impression of the central region of an Active Galactic Nucleus (AGN).
Active Galactic Nucleus (AGN) is the term used to refer to the central region of a galaxy that is so luminous that outshines the galaxy itself. About 10% of all galaxies in our Universe harbor an AGN at its center, these are the so called Active Galaxies. This artistic impression illustrates the different components found on an Active Galactic Nucleus (AGN)
At the center of the AGN is a supermassive black hole (around 100 million times heavier than our sun) that accretes matter in its surroundings forming an accretion disk around it about the size of our solar system. Due to the strong gravitational pool of the central black hole, this material spirals down heating up in the process. Further out, a torus of colder material surrounds the whole system. Clouds of inflowing or outflowing material give rise to strong winds. And even further out, clouds move around obscuring the central engine. Some AGN produce jets of outflowing material that are formed above the accretion disc perpendicular to it and can reach great distances from the central region forming what is called radio jets. The material in these jets moves at great speed (close to the speed of light) and is contained by magnetic fields.
You can download several versions:
Combined High Resolution Image (8300 x 3700 pixels, 300 dpi, 11.7 MB)
AGN with text High Resolution Image (4018 x 3508 pixels, 300 dpi, 5.41 MB)
AGN without text High Resolution Image (4018 x 3508 pixels, 300 dpi, 5.19 MB)