Discovery in the late 60's

During 1969-1973 the Vela spacecrafts that were designed for verifying whether the Soviet Union abided by the Limited Nuclear Test Ban Treaty of 1963, observed 16 peculiar and strong gamma-ray events. On the basis of arrival time differences, it was determined that they were related neither to the Earth nor to the Sun. This marked the discovery of Gamma-ray Bursts (GRBs), reported in a paper entitled ``Observations of Gamma-ray Bursts of Cosmic Origin'' [1]. Following the discovery of Gamma-ray Bursts (hereafter GRBs), many groups all over the world began development of new instrumentation to study the phenomenon.