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Evidence for low density holes in Jupiter's ionosphere
Masafumi Imai1, Ivana Kolmašová2,3, William S Kurth4
1Department of Physics and Astronomy, University of Iowa, Iowa City, IA, 52242, USA. masafumi-imai@uiowa.edu.
Nature Communications
|June 23, 2019
Summary
Jupiter
Area of Science:
- Planetary Science
- Space Physics
- Plasma Physics
Background:
- Jupiter's lightning generates electromagnetic impulses.
- These impulses create dispersed whistler emissions and non-dispersed radio pulses.
Purpose of the Study:
- To report the discovery of electromagnetic pulses linked to Jovian lightning.
- To investigate the characteristics of these pulses and their ionospheric implications.
Main Methods:
- Utilized the Juno Waves instrument during polar perijove passes.
- Analyzed electric field waveforms to detect and characterize Jupiter dispersed pulses (JDPs).
Main Results:
- Discovered and observed 445 JDP emissions.
- Estimated plasma densities (5.1–250 cm⁻³) and lengths (0.6 km–1.3 × 10⁵ km) of irregularities.
- Linked these irregularities to low-density holes (≤250 cm⁻³) in Jupiter's nightside ionosphere.
Conclusions:
- JDPs provide evidence for low-density plasma holes in Jupiter's ionosphere.
- These findings enhance our understanding of Jovian atmospheric and ionospheric processes.
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