Short answers, pulled from the story.
February 1969 marked the approval of Pioneer 11 and its twin probe, Pioneer 10. These spacecraft were designed to explore the outer Solar System and investigate the nature of the asteroid belt from a scientific standpoint.
The Pioneer 11 bus measured 3.6 meters deep with six panels forming a hexagonal structure and had a total mass of 259 kilograms. Four SNAP-19 radioisotope thermoelectric generators provided combined power of 155 watts at launch time.
Closest approach occurred on December 2 when it passed 42,828 kilometers above cloud tops during November and December 1974. Detailed images of the Great Red Spot reached Earth while gravitational pull from Jupiter altered the probe's trajectory toward Saturn.
the 1st of September 1979 marked Pioneer 11 passing Saturn at a distance of 20,591 kilometers from cloud tops. Instruments imaged one small moon within 6,676 kilometers of the spacecraft and discovered another previously undiscovered small moon plus an additional ring.
Power constraints prevented operation of any detectors by 1995 so decision makers shut down operations after nearly 22 years of exploration. NASA Ames Research Center issued a press release on the 29th of September 1995 announcing closure.
Slava Turyshev and colleagues conducted extended analysis decades later to determine the source was asymmetric thermal radiation creating thermal recoil force acting on spacecraft faces away from Sun. This resolved mystery after years of speculation about unknown forces affecting trajectory.