Science / Medicine : Huge Gamma Ray Source Detected

Three quasars throwing off violent gamma radiation 10 billion to 20 billion light-years away have been detected by a NASA observatory in orbit around the Earth, astronomers said last week. The quasars--star-like energy sources--are in the constellations Eridanus and Hercules and near the Crab Nebula. They are emitting “an extraordinary flux of gamma rays” whose total energy is estimated to be as much as 100 million times that of the total gamma-ray emissions of the Milky Way galaxy, said Carl Fichtel of the Goddard Space Flight Center in Greenbelt, Md.

“We do not know for certain what these sources are,” Fichtel said. “But we do know that the processes involved must be among the most violent in the universe.” In fact, each quasar is pouring out about 1,000 times as much energy in gamma rays alone as the entire Milky Way galaxy emits in all forms, Fichtel said.

Scientists are interested in gamma rays because they give clues to the processes occurring inside stars, quasars and other astronomical objects. When an individual atom undergoes a violent transformation inside a star, gamma rays frequently are emitted.