Observation of Turbulent Magnetohydrodynamic Cascade in the Jovian Magnetosheath

We present the first estimation of the energy cascade rate in Jupiter's magnetosheath (MS). We use in situ observations from the Jovian Auroral Distributions Experiment and the magnetometer investigation instruments on board the Juno spacecraft, in concert with two recent compressible models, to investigate the cascade rate in the magnetohydrodynamic (MHD) scales. While a high level of compressible density fluctuations is observed in the Jovian MS, a constant energy flux exists in the MHD inertial range. The compressible isothermal and polytropic energy cascade rates increase in the MHD range when density fluctuations are present. We find that the energy cascade rate in Jupiter's magnetosheath is at least 2 orders of magnitude (100 times) smaller than the corresponding typical value in the Earth's magnetosheath.

Automated summary

In this study, the first estimation of the energy cascade rate in Jupiter's magnetosheath is presented. In situ observations and compressible models are used to investigate the cascade rate in the magnetohydrodynamic scales. The study finds that while there are high levels of compressible density fluctuations in Jupiter's magnetosheath, there is a constant energy flux in the magnetohydrodynamic range. The energy cascade rate in Jupiter's magnetosheath is at least two orders of magnitude smaller than the typical value in Earth's magnetosheath.