This graphic shows the Pioneer 10 and Pioneer 11 flight paths through the Solar System. Credits: NASA
Launched on March 2, 1972, Pioneer 10 was the latest in a series of missions to explore space, which was still a very new frontier at the time. Accomplishing several firsts among spacecraft, it was the first to fly beyond Mars, the first to fly through the asteroid belt, first to swing by the planet Jupiter, and first to leave the solar system. While traversing the asteroid belt between Mars and Jupiter, Pioneer 10 faced the risk of colliding with bits of asteroids, anywhere from the size of a small particle to rocks as big as the state of Alaska.
Dec. 4, 1973, Pioneer 10 spacecraft sent back images of Jupiter of ever-increasing size. Credits: NASA
Once it made it's way through the asteroid belt, Pioneer 10 reached it's primary target, the planet Jupiter. It came within 81,000 miles (130,000 kilometers) of the surface as it sailed past. Images were beamed back to Earth revealing Jupiter as a liquid planet, while other instruments recorded information on Jupiter's radiation belts and magnetic fields.
Following its encounter with Jupiter, Pioneer 10 explored the outer regions of the solar system, studying energetic particles from the sun (solar wind), and cosmic rays entering our portion of the Milky Way. The spacecraft continued to make valuable scientific investigations in the outer regions of the solar system until its science mission ended on March 31, 1997 when it's power source failed and it became unable to send messages back to Earth.