Designated G306.3–0.9 after the coordinates of its sky position, the new object ranks among the youngest-known supernova remnants in the Milky Way. Astronomers estimate that a supernova explosion occurs once or twice a century in the Milky Way. The expanding blast wave and hot stellar debris slowly dissipate over hundreds of thousands of years, eventually mixing with and becoming indistinguishable from interstellar gas. Like fresh evidence at a crime scene, young supernova remnants give astronomers the best opportunity for understanding the nature of the original star and the details of its demise.
"The Swift survey leverages infrared imaging previously compiled by NASA's Spitzer Space Telescope and extends it into X-ray and higher energies," said team member Michael Siegel, a Penn State research associate at the Mission Operations Center for Swift at Penn State. "The infrared and X-ray surveys complement each other because light at these energies penetrates dust clouds in the galactic plane, while the ultraviolet is largely extinguished."
Supernova remnants emit energy across the electromagnetic spectrum, from radio to gamma rays, and important clues can be found in each energy band. X-ray observations figure prominently in revealing the motion of the expanding debris, its chemical content and its interaction with the interstellar environment, but supernova remnants fade out in X-ray light after 10,000 years. Indeed, only half of those known in the Milky Way galaxy have been detected in X-rays at all.