Magnetars

On March 5, 1979, astronomers saw a burst of gamma rays so strong it swamped their detectors. Another rare burst in 1998 helped confirm the existence of magnetars, intensely powerful magnetic stars, unusual enough that there might only be a dozen or so in the galaxy. Another one has just been found --when it let off a burst last December that, for a fraction of a second, was brighter than the full moon. [from MetaFilter.com]