Pioneer 11 spacecraft
Pioneer 11 image of Jupiter
Pioneer 11 image of Saturn
Pioneer 11 spacecraft

Pioneer 11 spacecraft

Courtesy of NASA



Overview
Pioneer was a series of unmanned space probes launched over a period of 20 years. Pioneers 10 and 11 are most famous because they were sent to explore the outer solar system, and then eventually go beyond our solar system into interstellar space.


Launch
April 5, 1973


Arrival
Jupiter in 1974 and Saturn in 1979


End of Mission
The mission officially ended on September 30, 1995 when the last data transmission was received. Pioneer 11 continues to coast through deep space and will take 4 million years to reach a star in the constellation Aquila.


Goals
Investigate Jupiter, Saturn, and the outer solar system. Study energetic particles in the outer solar system (heliosphere).


Findings
Pioneer 11 was the first craft to explore the planet Saturn and its main rings. Pioneer 11, like Pioneer 10, used Jupiter’s gravitational field to change its trajectory. It passed close to Saturn and then it followed an escape trajectory from the solar system. Pioneer 11 ended its transmissions when its power source was exhausted. It is now headed toward the constellation Aquila.