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Active galaxies often display radio lobes created by relativistic jets. Cygnus A is a galaxy with two conical relativistic streams which travel far beyond the galaxy before they slow and spread out in the intergalactic medium. These jets originate in a galactic black hole, see animation & picture at: http://www.cv.nrao.edu/~abridle/dragnparts.htmOur galaxy's black hole is currently rather passive, but has been more active in the past. This has blasted some material out along the axis, but because it is intermittent, it has slowed down and spread out as soon as it leaves the plane of the galaxy. See picture at http://www.skyandtelescope.com/community/skyblog/newsblog/Galactic-Bubbles-Spark-Debate-186963791.htmlThere are cases where the relativistic jets have a sudden bend (symmetrical on both sides of a galaxy). Could this be due to the merger of two galactic black holes, which changes the axis of rotation, and this the direction of the relativistic jets?PulsarsThe common theory about pulsars are that they are spinning neutron stars.Like a black hole, nearby gas and dust will form an accretion disk around a neutron star, and magnetohydrodynamic forces in the accretion disk may result in directing matter in high-speed jets out along the axis of rotation.There is a movie of the Vela Pulsar at X-Ray wavelengths here: http://en.wikipedia.org/wiki/PulsarIn this case, the axial jet seems to have a steady axis (not precessing). The matter is ejected along the axis at high speed until it hits the interstellar medium, slows and spreads out. The axial jets are not the source of the pulsing light, since in this case, we are not seeing the jets end-on. Unlike a black hole, the neutron star does not have an event horizon, so an event horizon is not necessary to produce high-speed jets.