Twenty-seven years ago today, on September 1, 1979, Pioneer 11 passed by Saturn at a distance of 21,000 km. Launched from Cape Canaveral on April 6, 1973, Pioneer 11 was the second spacecraft to reach Jupiter and the first to explore Saturn's rings. Less than three meters long, Pioneer 11 featured high-gain, low-gain and medium-gain antennas and two radioisotope thermoelectric generators (RTG) which together produced only 100 W by the time the spacecraft reached Saturn. Three pairs of rocket thrusters provided spin-axis control and could be pulsed or fired steadily. Instrumentation included a magnetometer, plasma analyzer, ion detector, charged particle detector, ultraviolet photometer, and infrared radiometer.
Pioneer 11 charted Saturn's magnetosphere, discovered two additional moons, and determined that Titan, a large-planet sized moon, was too cold to support life. NASA scientists were treated to breathtaking pictures of Saturn's rings, which appeared darker in Pioneer's pictures than in telescopic observations from Earth. After flying by Saturn, Pioneer 11 continued its course towards the outer reaches of our solar system. Routine operations ended on September 30, 1995. Communications ended just over one month later. Today, Pioneer 11 continues its journey towards the constellation of Aquila. Should extraterrestrials ever encounter the craft, a plaque that bears depictions of a man, a woman, and location of the Sun and the Earth attests to Pioneer 11's origins.
Resource:
http://en.wikipedia.org/wiki/Pioneer_11
Pioneer 11 and Voyager 1
