The Crab Nebula is an expanding remnant of a star's supernova explosion. Located 6,500 light-years away, this glowing relic has been expanding since the star exploded, and it is now approximately 11 light-years in width.
The orange filaments are the tattered remains of the star and consist mostly of hydrogen. The rapidly spinning neutron star embedded in the center of the nebula is the dynamo powering the nebula's eerie interior bluish glow. The blue light comes from electrons whirling at nearly the speed of light around magnetic field lines from the neutron star, which is the crushed ultra-dense core of the exploded star.
Publication: December 1, 2005