Back in 2005, NASA's Cassini spacecraft first recorded some radio waves being emitted from Saturn, known as Saturn Kilometric Radiation (SKR). Even in 2011, it continues to orbit and gather data on Saturn, including SKR, which can be converted into sounds that are audible to the human ear. Although radio waves from planets had been recorded before, Cassini's instruments are of a higher resolution than those of previous crafts, such as NASA's Voyager, which allows it to gather more information and to "convert the radio waves into audio recordings by shifting the frequencies down into the audio frequency range".
The resulting sounds are quite eerie; sounding more like the soundtrack to a creepy sci-fi horror movie than the emissions of a majestically beautiful planet. However, this phenomenon isn't limited to Saturn, and was also first recorded on Earth in 1979. The radio waves coming from both planets produced very similar sounds, and scientists believe that both are related to the Aurora Borealis on Earth and the auroras at Saturn's Northern and Southern poles.