Illustration of a quasar's emission and magnetic field. A quasar is a galaxy which has a super massive black hole at it's centre and is characterised by the emission of high energy jets of material. The supermassive black hole's corona (blue) is threaded by magnetic fields (white). The corona lies above a much denser disk of material (red and yellow), swirling around and falling towards the black hole. Jets of material are shown being emitted from the black hole and corona in opposite directions.