andlt;strongandgt;Microquasarandlt;/strongandgt; artwork. A microquasar is a smallblack hole orbiting a larger star. The black holesends out fast jets of plasma (one seen, blue,lower centre to top right) from its poles. Itsimmense gravitational pull sucks matter from itscompanion star (blue), forming an orbitingaccretion disc (white, lower centre) around thehole. This emits X-rays as it rotates faster andgets hotter as it nears the hole. The jets emitradio waves, and are similar to those seen emittedfrom quasars. A quasar is a supermassive blackhole found at the centre of some active galaxieswhich makes the galaxyandamp;apos;s nucleus extremely bright.