GRB 670702 is a gamma ray burst (GRB) known for being the first gamma ray burst detected in history. It was detected on 2 July 1967 by the Vela 4 satellite, a US satellite that monitored worldwide compliance with the 1963 nuclear test ban treaty. The event lasted around ten seconds with an energy emission in the MeV band and a double pulse light curve. Its properties were distinct from those expected from a nuclear test in space. Directional information strongly suggested an origin distinct from the Earth or Sun.
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