Vela Supernova Remnant in Optical
About 11,000 years ago a star in the constellation of Vela exploded. This bright supernova may have been visible to the first human farmers . Today the Vela supernova remnant marks the position of a relatively close and recent explosion in our Galaxy . A roughly spherical, expanding shock wave is visible in X-rays . In the above optical photograph, the upper left corner of the spherical blast wave is shown in detail. As gas flies away from the detonated star , it reacts with the interstellar medium , knocking away closely held electrons from even heavy elements . When the electrons recombine with these atoms , light in many different colors and energy bands is produced.