Final answer:
Accretion onto black holes is the process in which matter-stars, dust, and gas-orbiting in the dense nuclear regions of a galaxy spirals towards a central black hole. This matter forms an accretion disk around the black hole and as it spirals closer, it accelerates and becomes compressed, releasing prodigious amounts of energy.
Step-by-step explanation:
In a galaxy, a central black hole attracts matter-stars, dust, and gas-orbiting in the dense nuclear regions. Accretion onto black holes is the process in which matter-stars, dust, and gas-orbiting in the dense nuclear regions of a galaxy spirals towards a central black hole.
This matter forms an accretion disk around the black hole and as it spirals closer, it accelerates and becomes compressed, releasing prodigious amounts of energy. This matter spirals in toward the spinning black hole and forms an accretion disk of material around it.
As the material spirals ever closer to the black hole, it accelerates and becomes compressed, heating up to temperatures of millions of degrees. Such hot matter can radiate prodigious amounts of energy as it falls in toward the black hole.