These x-ray images show recent activity of the Crab Pulsar, the core of the star that was destroyed in the Crab Nebula’s supernova explosion. The core is a pulsar (the circle near the images’ center), a type of neutron star that spins rapidly and emits synchrotron radiation from two poles. The x-ray emissions are given in false color to show their intensity. In descending order, the intensity levels are white, blue- green, yellow, and red. The images in this series were taken at intervals matching those measured for the pulsation of the radio emission. The effect is stroboscopic: the white circle near the center, which represents the most intense x-ray emission from the pulsar, seems to blink on and off more than 30 times per second; the same