Image of the Crab Nebula, which is located about 6,500 light-years from Earth, and is remnant of a star that began its life with about 10 times the mass of our own Sun. The Crab star exploded on July 4, 1054. The core of the star survived the explosion as a "pulsar". The pulsar has about 1.4 times the mass of the Sun, but is inside an object only about 10 miles in diameter, known as a "neutron star". The neutron star spins on its axis 30 times a second. The colors in the image is material from the outer layers of the star that was expelled during the explosion and is now expanding outward at high speed.