Pioneer 10 flyby Jupiter 1973

Pioneer 10, launched March 2, 1972, made its closest approach to Jupiter December 4, 1973.  It was the first spacecraft to travel through the asteroid belt and encounter the biggest planet in our solar system. Pioneer 10 passed within 81,000 miles of the cloud tops of Jupiter.  It took measurements of Jupiter's magnetosphere, radiation belts, magnetic field and atmosphere.  These measurements helped in the design of the Voyager and Galileo spacecraft.