A Juno model of the Io - Jupiter electromagnetic interaction

Juno’s highly elliptical polar orbit offers unique in-situ measurements of the electrodynamic interaction between Jupiter and its moon Io. These occur both near Io and near the surface of Jupiter and at distances between. Magnetic field data obtained during multiple traversals of magnetic field lines connected to the orbit of Io reveal remarkably rich and complex current densities along flux tubes connected to Io’s position along its orbit. Using Juno’s many traversals of Io's flux tube (IFT), we derive a model of the strength of the interaction with regards to distance along Io’s extended tail and Io’s position in the plasma torus, illuminating the interaction of Jovian magnetospheric plasma with Io and setting important constraints in the Io-Jupiter interaction.The model is based on an inverse methodology to distribute currents along  the IFT in such a way as to match the magnetic field signature observed during Juno’s traversals of the IFT as well as passages near the IFT. We derive, by means of non-linear optimization, the distribution of current within the IFT (during traversals) as well as the size and morphology of the IFT that best fits the magnetic field observations. We compare our results with observations of the IFT obtained near Io as Voyager 1 passed nearby.