Quasars are extremely luminous galactic cores where gas and dust falling into a central supermassive black hole emit enormous amounts of light. Due to their exceptional brightness, these objects can be seen at high redshifts, i.e., large distances. Quasars are extremely luminous galactic cores where gas and dust falling into a central supermassive black hole emit enormous amounts of light. Due to their exceptional brightness, these objects can be seen at high redshifts, i.e., large distances. Astronomy Phys.org – latest science and technology news stories