The discovery of counterparts in X-ray and optical to radio wavelengths has revolutionized the study of γ -ray bursts, until recently the most enigmatic of astrophysical phenomena. We now know that γ -ray bursts are the biggest explosions in nature, caused by the ejection of ultrarelativistic matter from a powerful energy source and its subsequent collision with its environment. We have just begun to uncover a connection between supernovae and γ -ray bursts, and are finally constraining the

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... erties of the ultimate source of γ -ray burst energy. We review here the observations that have led to this breakthrough in the field; we describe the basic theory of the fireball model and discuss the theoretical understanding that has been gained from interpreting the new wealth of data on γ -ray bursts. Ik zie een ster I see a star en onder mij and beneath me zakt de aarde langzaam weg. the Earth slowly falls away.