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Abstract Jupiter's rapidly rotating magnetosphere, with internal plasma sources such as the volcanic moon Io, provides a unique natural laboratory for studying internally driven planetary magnetospheres. Using the Grid Agnostic Magnetohydrodynamics for Extended Research Applications (GAMERA) model, we simulated Jupiter's magnetosphere with variable ionospheric Pedersen conductances, which is mainly responsible for energy dissipation between the ionosphere and magnetosphere though convection. We chose values ranging from 0.5 to mho to investigate the Pedersen conductance's role in controlling mid‐magnetosphere region's dynamics and the closing of magnetosphere‐ionosphere currents. Simulated density, temperature, and radial and azimuthal flows in the equator are compared with observations from the Jovian Auroral Distributions Experiment (JADE) on the Juno spacecraft. All simulation cases exhibit dawn‐dusk asymmetries, in both the ionosphere and magnetosphere. The 0.5 case showed the best agreement with JADE observations, while the 1 case exhibited a magnetic topology more consistent with the auroral observations from the Hubble Space Telescope and Juno. These results enhance our understanding of Jupiter's magnetosphere‐ionosphere coupling, provide context for observations, and inform the background parameters of future test particle simulations and data‐model comparisons using the GAMERA model.
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This content will become publicly available on April 1, 2027
Global Energy Circulation During a Solar Wind Density Pulse
Abstract We study the propagation and impacts of a strong density pulse through the magnetosphere during 11:40–12:00 UT near the peak of a geomagnetic storm on 3 February 2022. Using the Space Weather Modeling Framework Geospace global simulation, we show how the energy transport in the magnetosphere is enhanced promptly after the pulse arrival at the dayside magnetosphere, causing enhanced flows in the magnetotail prior to the compression reaching the tail region. The flows are shown to transport energy into the inner magnetosphere and couple to the dawn sector ionosphere, where the magnetic field variations caused large geomagnetically induced currents. We discuss the characteristics of pulse‐driven disturbances in the magnetosphere—ionosphere system, and argue that despite some similarities, the activity is distinct from substorms.
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- Award ID(s):
- 2420675
- PAR ID:
- 10696274
- Publisher / Repository:
- AGU
- Date Published:
- Journal Name:
- Space Weather
- Volume:
- 24
- Issue:
- 4
- ISSN:
- 1542-7390
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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