If a star exploded somewhere in space with a violence dwarfed only by the Big Bang, you'd think folks would notice. Sometime yesterday, however, just such a cosmic detonation probably took place, and almost nobody on Earth was the wiser. Sometime today there's likely to be another one.
The cosmic cataclysms are known as gamma-ray bursts-- distant explosions, invisible to the human eye, that in seconds release more energy than our own little sun will put out in its 10 billion-year lifetime. Though astronomers have studied hundreds of gamma bursts, they have never determined what they are. Soon that may change....