The “Black Widow” pulsar moves at a speed of KM/hr. A bow shock wave is the greenish crescent shape. The pressure behind the bow shock creates a second shock wave that sweeps the cloud of high-energy particles back from the pulsar to form the cocoon.
Why galaxies turn into cosmic graveyards- Supermassive black hole winds keep galaxies turned off, scientists theorize. Scientists finally confirm a long-held theory that supermassive black holes suppress star formation in dormant galaxies.
Observations from NASA's Spitzer Space Telescope provide strong evidence that the slender, bulgeless galaxies can, like their chubbier counterparts, harbor supermassive black holes at their cores in this artist concept.