April 1, 1997: The Hubble telescope has made an important contribution toward solving one of astronomy's greatest enigmas by allowing astronomers to continue watching the fading visible-light counterpart of a gamma-ray burst, one of the most energetic and mysterious events in the universe.
The so-called optical counterpart is presumably a cooling fireball from the catastrophic event that triggered the massive burst of invisible gamma rays ? the highest-energy radiation in the universe. This event may have unleashed as much energy in a few seconds as the Sun does in 10 billion years! The orange dot in the center of this Hubble image represents the burst's visible-light glow.See the rest: