These images of the remnant of a tremendous stellar explosion are giving astronomers a remarkable look at the dynamic relationship between the tiny crab pulsar and the vast nebula that it powers. The image shows the entire crab nebula, the remnant of a supernova explosion, witnessed over 900 years ago. The nebula which is 10 light years across, is 7000 light years away, in the constellation Taurus. The green, yellow and red filaments, concentrated towards the edges of the nebula, are remnants of the star that were ejected into space by the explosion. At the center of the crab nebula lies the crab pulsar, the collapsed core of the exploded star. The crab pulsar is a rapidly rotating neutron star, an object only about 6 miles across, but containing more mass than our Sun. As it rotates at a rate of 30 times per second, the crab pulsar's powerful magnetic field sweeps around, accelerating particles and whipping them out into the nebula at speeds close to the speed of light. The blue glow in the inner part of the nebula, light emitted by energetic electrons that spiral through the crab's magnetic fields, is powered by the crab pulsar.