The Pioneer program was a series of space missions launched by NASA in the 1970s. Its primary goal was to explore the outer planets of our solar system, including Jupiter and Saturn. The program included several spacecraft, notably Pioneer 10 and Pioneer 11, which provided valuable data about planetary atmospheres, magnetic fields, and radiation belts. Pioneer 10 was the first spacecraft to travel through the asteroid belt and reach Jupiter, while Pioneer 11 followed, becoming the first to fly by Saturn. These missions significantly advanced our understanding of the solar system and laid the groundwork for future explorations, such as the Voyager program.