astralavista

The Universe may be big and empty but it's certainly not silent. The cosmos is roaring with all kind of ruckus. Quasars emit massive beams of radio waves, and so do centers of galaxies, massive neutron stars and other exotic cosmic inhabitants.
But you don't need to be big and heavy to grind out radio signals. The solar system puts on a radio show, too, and astronomers have long been tuning in.
Scientists from the University of Iowa, using NASA's Cassini spacecraft, have now recorded two particularly cool and creepy samples from Radio Saturn. (Listen in here and here.)
The scientists said that the radio signals, which they called "Halloween sound track," are related to Saturn's auroras, or northern and southern lights.
The scientists also said that time on this recordings has been compressed and their frequencies down-shifted since the broadcasts were high above the audible frequency range.
The research was published in the current issue of the Geophysical Research Letters.
(For comparison, here's a recorded signal of Radio Jupiter.)

Image: The image corresponds with the first sample from Saturn. "It appears as though the three rising tones are launched from the more slowly varying narrowband emission near the bottom of this display," the scientists said. "If this is the case, it represents a very complicated interaction between waves in Saturn's radio source region, but one which has also been observed at Earth." Credit: NASA/JPL/University of Iowa