GANYMEDE - A NEW RADIO-SOURCE

Observations by the Galileo plasma wave receiver during the first two flybys of Ganymede revealed that this Jovian moon is the source of nar rowband electromagnetic radio waves, making it the only satellite in t he solar system known to generate non-thermal radio emissions. The emi ssions are the result of mode-coupling from electrostatic electron cyc lotron emissions near the upper hybrid resonance frequency, similar to non-thermal continuum radiation found at the known magnetized planets .