X-ray pulsars are thought to be neutron stars, extremely dense remains of the core of a massive star. X-ray pulsars spin very rapidly (rotating tens or hundreds of times per second) and possess very strong magnetic fields. Jets of energetic particles shoot out of the magnetic poles and the pulsars are surrounded by large clouds of hot ionized gas. The image on the left shows a new image of the Vela pulsar obtained by the Chandra X-ray observatory. The pulsar is located at the bright spot at the center of the image; the bright jet can be seen emanating diagonally from the pulsar; and rings of X-ray emission from high energy particles produced by the central neutron star can be seen to the upper right of the pulsar. Surprisingly the jet points in the direction of the motion of the pulsar (shown as the green arrow in the righthand corner), which suggests that the jet at the bottom left actually accelerates the pulsar through space like a rocket engine. The Chandra image of another X-ray pulsar, the Crab pulsar, is remarkably similar to the Vela image: the Crab also possesses jets along with swirling clouds of hot gas further from the pulsar. In fact the similarity in X-ray morphology between the 2 X-ray pulsars is truly startling, as can be seen in this movie (in QuickTime format), in which the scaled image of the Crab (in blue) is gradually overlaid on the image of the Vela pulsar.