Matter Flowing into the Black Hole

Matter flowing into the black hole at the heart of an active galaxy flows first through an opaque torus of gas and dust and then into the accretion disk.

The inner parts of the accretion disk are very hot, and some of the gas is ejected in oppositely directed jets while the rest of the gas flows into the black hole. The inner parts of the accretion disk produce broad emission lines, while gas clouds above and below the disk produce narrow emission lines. According to the unified model, the angle at which we view this structure determines the kind of radio galaxy we see.