Neutral Wind Control of Jupiter's Non-Auroral Ionosphere

We use JAMMIES (JAMMIES is Another Model Making Ionospheric EStimates), a new model of Jupiter's non-auroral ionosphere, to demonstrate that neutral wind-driven field-aligned plasma transport can explain decades of measurements inconsistent with a solar-dominated ionosphere. Two observations highlight these inconsistencies: a minimum in (Formula presented.) emission along the magnetic equator where solar ionization maximizes, and a systematic asymmetry where vertical dawn plasma densities exceed those at dusk. JAMMIES models the chemical and dynamical evolution of plasma in a dipole coordinate system. Observed (Formula presented.) emissions can be reproduced via two mechanisms: (i) field-aligned neutral-ion collisions driven by a steady-state global neutral wind pattern, or (ii) field-perpendicular electrodynamic plasma drifts at the magnetic equator. Mechanism (i), induced by persistent auroral heating, also reproduces disparate vertical plasma profiles. Results show that neutral wind-driven dynamics dominate Jovian ionospheric structure, which is found to be spatially variable but temporally stable.