摘要：

New observations by the ISEE 1 plasma wave receiver reveal heretofore unreported details of the nonthermal continuum radiation from the earth. In particular, the higher frequency escaping component shows temporal and spectral features which are quite different from those of the lower frequency trapped emission. The higher frequency component is often clearly separated in frequency from the trapped component and high resolution spectrograms show that the escaping radiation consists of numerous narrowband emissions which drift slowly in frequency with time. The higher frequency component also exhibits greater temporal and spatial variability in both amplitude and frequency although the temporal variations are still quite smooth when compared to the more intense and higher frequency auroral kilometric radiation. Evidence is presented which clearly shows a direct connection between intense electrostatic emissions near the upper hybrid frequency and the escaping continuum radiation and strongly suggests the latter electromagnetic emission is generated through mode coupling with the upper hybrid waves. The new ISEE observations of the escaping continuum radiation from the earth strongly suggest a close correspondence with the newly reported narrowband kilometric radiation from Jupiter. Both emissions are relatively narrowband and show slow variations in amplitude with time. In both cases, the narrowband radiation lies above the trapped continuum radiation and below the intense extraordinary mode emissions (auroral kilometric radiation at the earth and decametric radiation at Jupiter). Evidence from both planets suggests the radiation is generated by intense electrostatic waves near the upper hybrid resonance frequency in the vicinity of the plasmapause at the earth and at the outer edge of the Io plasma torus at Jupiter.

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