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Voyager planetary radio astronomy studies
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Staelin, David H. Eikenberry, Stephen S. |
| Copyright Year | 1993 |
| Description | Analysis of nonthermal radio emission data obtained by the Planetary Radio Astronomy (PRA) spectrometers on the Voyager 1 and 2 spacecraft was performed. This PRA data provided unique insights into the radio emission characteristics of the outer planets because of PRA's unique spectral response below the terrestrial ionospheric plasma frequency and its unprecedented proximity to the source. Of those results which were documented or published, this final report surveys only the highlights and cites references for more complete discussions. Unpublished results for Uranus, Neptune, and theoretical Ionian current distributions are presented at greater length. The most important conclusion to be drawn from these observations is that banded spectral emission is common to the radio emission below 1-2 MHz observed from all four Jovian planets. In every case multiple spectral features evolve on time scales of seconds to minutes. To the extent these features drift in frequency, they appear never to cross one another. The Neptunian spectral features appear to drift little or not at all, their evolution consisting principally of waxing and waning. Since other evidence strongly suggests that most or all of this radio emission is occurring near the local magnetospheric electron cyclotron frequency, this implies that this emission preferentially occurs at certain continually changing planetary radii. It remains unknown why certain radii might be favored, unless radial electric field components or other means serve to differentiate radially the magnetospheric plasma density, particle energy vectors, or particle coherence. Calculation of the spatial distribution and intensity of the Io-generated magnetospheric currents are also presented; these currents may be limited principally by wave impedance and local field strengths. |
| File Size | 1460496 |
| Page Count | 32 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19940019855 |
| Archival Resource Key | ark:/13960/t5hb4219d |
| Language | English |
| Publisher Date | 1993-12-23 |
| Access Restriction | Open |
| Subject Keyword | Lunar And Planetary Exploration Voyager 1 Spacecraft Cyclotron Radiation Cyclotron Frequency Nonthermal Radiation Space Plasmas Radio Emission Radio Astronomy Gas Giant Planets Spectral Emission Current Distribution Plasma Frequencies Electric Fields Voyager 2 Spacecraft Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
