Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Gamma-ray bursts are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the brightest electromagnetic events known to occur in the universe. Most observed gamma-ray bursts are believed to consist of a narrow beam of intense radiation released during a supernova as a rapidly rotating, high-mass star collapses to form a neutron star, quark star, or black hole. Learn more about gamma-ray bursts, their origins and scientific significance in the following pages.