The Electromagnetic Response of a 3D Heterogeneous Europan Ocean

A central objective of the Europa Clipper is to constrain the geometry and physical properties of the Europan ocean. The campaign of close flybys by Clipper allows for an extensive survey of how electromagnetic (EM) fields induced within the ocean vary across the surface of Europa, a dramatic improvement on the data currently available from the Juno and Galileo missions.

We developed a solver to model the full induced EM response of a Europan ocean heterogeneous in composition (e.g. salinity and temperature) and geometry (heterogeneous ice thickness scenario) to a realistic external field constructed from multiple time harmonics at the significant inducing frequencies of the Jupiter-Europa system. The method is extensible to arbitrarily complex ocean and external field structures. Our focus is on equatorial zonal conductivity structures, which drive additional higher-order field anomalies together with the classical dipolar response field of a homogeneous ocean. We use these models to assess the capability of Europa Clipper to survey the spatial structure of the ocean and search for ocean homogeneities and current structures. We report significant changes in field strength and morphology close to anomaly regions, which could propagate far enough from the surface to be detectable by the Clipper magnetometer."