Telescope Trick Reveals the Ghostly Glow Left by a Dead Star

Astronomers have caught sight of two stars that went kaboom only 2.5 billion years after our universe was created in the Big Bang, and say that ancient explosions are the oldest and most distant supernovas ever discovered. Researchers plan to use the new technique used to identify these supernovas to find other stars that blew up in the universe's early days, which may aid our understanding of how the universe was seeded with heavy elements.