The Vela pulsar is a neutron star about 12 miles in diameter, itself spinning at a dizzying 11 times per second and the brightest and most persistent source of gamma rays in the sky. The pulsar and the supernova remnant was created by a massive star which exploded over 10,000 years ago. Due to its behavior, it produces tremendously powerful electric and magnetic fields, which go on to accelerate particles in the remnant to nearly the speed of light. In effect, the pulsar is producing a vast, natural particle accelerator.
As the ejecta from the explosion expanded into space and collided with the surrounding interstellar gas, shock waves were formed and heated the gas and ejecta to millions of degrees. The sphere of hot gas is about 100 light years across, 15 times larger than the region shown in this image, and is expanding at a speed of about 400,000 km/hr.
The pulsar is considered to be one of the most fascinating images ever captured by the Chandra X-ray Observatory, revealing a striking, almost unbelievable, structure consisting of bright rings and jets of matter. Such structures indicate that mighty ordering forces must be at work amidst the chaos of the aftermath of a supernova explosion. Forces can harness the energy of thousands of suns and transform that energy into a tornado of high-energy particles that astronomers refer to as a "pulsar wind nebula."
The Vela pulsar is the collapsed stellar core within the Vela supernova remnant --the massive star that formed this structure blew up between 11,000 and 12,300 years ago, astronomers have established.
More massive than the Sun, it has the density of an atomic nucleus.The pulsar's electric and magnetic fields accelerate particles to nearly the speed of light, powering the compact x-ray emission nebula revealed in the Chandra image below.
The Daily Galaxy via Fermi Space Telescope
Image credit: NASA, DOE, International Fermi LAT Collaboration, http://chandra.harvard.edu/photo/2003/vela_pulsar/index.html, and NASA/CXC/PSU/G.Pavlov et al.