New discoveries on odd stellar explosions

Image Credit: NASA/Swift/Penn State/J. Kennea

Over the last week and a half, there have been a couple of news releases about stellar explosions. In the first story, astronomers have spotted a puzzling blast of gamma ray and X-ray emission that could be a star being ripped apart by a massive black hole. In the other story, astronomers have made substantial progress in understanding the brightest supernovae ever observed.

First, the puzzling gamma rays. For decades, astronomers have seen sudden, short bursts of gamma rays coming from all over the sky. About ten years ago, after a lot of hard work (and a little luck) by many different researchers, most astronomers came to believe that many of these "gamma-ray bursts" are the birthing cry of new black holes formed at the centers of massive, exploding stars.

Several space missions have been studying these gamma-ray bursts, including the currently-operating Swift satellite. These satellites automatically detect the few-second long burst of gamma rays, locate where in the sky they are coming from, and send emails and instant messages to astronomers around the globe alerting them to the event. Especially interesting events can get rapid observations from large telescopes and major satellites such ...