Pioneer 3 was a spin-stabilized spacecraft intended as a lunar probe but failed to perform a lunar flyby as planned. Its mission was revised to measure radiation in the outer Van Allen radiation belts. December 6, 1958 at 05:44 UTC · Launch Successful Juno II — National Aeronautics and Space Administration, to Lunar flyby Launch Complex 5, Cape Canaveral SFS, FL, USA The world's 30th orbital launch attempt, and 27th of 1958. Data: Launch Library 2, The Space Devs. Image via The Space Devs.