A "supernova" is a powerful and explosive event that happens when a star nears the end of its life. It releases an immense amount of energy, causing a bright and dazzling explosion in space. Full definition
More common lower - energy cosmic rays — thought to emerge in the aftermath of supernova explosions in the Milky Way — curve so much in the galaxy's magnetic field that they appear to come from all over the sky. (sciencemag.org)
The key agents in this are cosmic rays, which are energetic particles coming from the interstellar media — they come from remnants of supernova explosions mainly. (discovermagazine.com)
CE: If the first stars to evolve were somehow extremely large, they would have exploded as supernovas in only a few tens of millions of years. (creationscience.com)