A determination of the source of Jovian hectometric radiation via occultation by Ganymede

During the first Galileo flyby of Ganymede, Jovian radio emissions in the frequency range of 700 kHz to 5.6 MHz were completely occulted by the satellite. We take advantage of this serendipitous observation to determine the location of the radio emission source relative to Jupiter. The evidence suggests that the apparent source is along an L≳7 magnetic field line near the central meridian longitude (∼160°) of the spacecraft and at 1 to 3 Jovian radii above the northern hemisphere of Jupiter. These results are consistent with a source located along either the Ganymede or Europa flux tube.