NASA officially creates the OPWG (Outer Planets Working Group), with the mandate to define experimental missions for the exploration of the outer Solar System. Its member is Gary Flandro, an aerospace engineer at JPL, in his early twenties. This led to the birth of the Pioneer F and G missions (later Pioneer 10 and 11), followed by Mariner 11 and 12 (later Voyager 1 and 2), and Mariner 13 and 14 (which never materialized, but would have become Voyager 3 and 4).
