Welcome to KSAT, the radio station broadcasting from the poles of Saturn. For years, scientists have been puzzled by the pulsing intensity of radio emissions from the ringed planet. Puzzling, because the scientists couldn't key the pulses to any known phenomenon. The 11-hour intervals approximated but didn't match Saturn's rotation rate, so the planet's magnetic field couldn't be the source. Nor could scientists find any connection between the radio-signal intensity and variations in the solar wind. Now researchers examining 5 years of images from the Hubble Space Telescope and the Cassini spacecraft, which orbits Saturn and its moons, say they've found a clue. In an upcoming issue of Geophysical Research Letters, a team reports that the variations in radio signal coincide with the intensity of the planet's auroras. That revelation doesn't solve the mystery, however. So scientists have started looking for the cause of the auroral variations. One prime candidate: particle emissions from Saturn's moon Enceladus.
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