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| Titel |
Jupiter's Decameter Radiation as Viewed from Juno, Cassini, WIND, STEREO A, and Earth-Based Radio Observatories |
| VerfasserIn |
Masafumi Imai, William S. Kurth, George B. Hospodarsky, Scott J. Bolton, John E. P. Connerney, Steven M. Levin, Tracy E. Clarke, Charles A. Higgins |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250142387
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| Publikation (Nr.) |
 EGU/EGU2017-6003.pdf |
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| Zusammenfassung |
| Jupiter is the dominant auroral radio source in our solar system, producing decameter (DAM)
radiation (from a few to 40 MHz) with a flux density of up to 10−19 W/(m2Hz). Jovian DAM
non-thermal radiation above 10 MHz is readily observed by Earth-based radio telescopes that
are limited at lower frequencies by terrestrial ionospheric conditions and radio frequency
interference. In contrast, frequencies observed by spacecraft depend upon receiver
capability and the ambient solar wind plasma frequency. Observations of DAM from
widely separated observers can be used to investigate the geometrical properties
of the beam and learn about the generation mechanism. The first multi-observer
observations of Jovian DAM emission were made using the Voyager spacecraft and
ground-based radio telescopes in early 1979, but, due to geometrical constraints and
limited flyby duration, a full understanding of the latitudinal beaming of Jovian
DAM radiation remains elusive. This understanding is sorely needed to confirm
DAM generation by the electron cyclotron maser instability, the widely assumed
generation mechanism. Juno first detected Jovian DAM emissions on May 5, 2016, on
approach to the Jovian system, initiating a new opportunity to perform observations of
Jovian DAM radiation with Juno, Cassini, WIND, STEREO A, and Earth-based
radio observatories (Long Wavelength Array Station One (LWA1) in New Mexico,
USA, and Nançay Decameter Array (NDA) in France). These observers are widely
distributed throughout our solar system and span a broad frequency range of 3.5 to
40.5 MHz. Juno resides in orbit at Jupiter, Cassini at Saturn, WIND around Earth,
STEREO A in 1 AU orbit, and LWA1 and NDA at Earth. Juno’s unique polar trajectory
is expected to facilitate extraordinary stereoscopic observations of Jovian DAM,
leading to a much improved understanding of the latitudinal beaming of Jovian DAM. |
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