The center of our galaxy is a black hole called, "Sagittarius A Star", in the direction of Sagittarius. An accretion disc surrounds it. These are gases and dust moving at a very high speed, (almost the speed of light), creating tremendous friction, temperature (in the millions of degrees), and a magnetic field, moving too fast to fall into the hole unless they slow down. All this energy creates a magnetic field and is thought to create explosive jets that shoot hundreds of light years into deep space from the black hole obliterating everything in their path. Thought to be essential to tear stars apart and chop up galaxies for new star formation.