Status and Latest Results from NASA’s Electrojet Zeeman Imaging Explorer (EZIE)

EZIE, the Electrojet Zeeman Imaging Explorer, is a NASA three-Cubesat Heliophysics mission launch on March, 14, 2025. It employs four downward and cross-track looking miniaturized radiometers on each of the 6U CubeSat, flying in a pearls-on-a-string managed formation, to measure, for the first time, the two-dimensional structure and the temporal evolution of the electrojets flowing at altitudes of ~100–130 km. The four identical radiometers simultaneously measure polarimetric radiances of the molecular oxygen thermal emission at 118 GHz and employs the Zeeman sensing technique to obtain the current-induced magnetic field vectors at ~80 km, an altitude region very close to the electrojet.  This measurement technique allows for the remote sensing of the meso-scale structure of the electrojets at four different cross-track locations simultaneously at altitudes notoriously difficult to measure in situ. Differential drag maneuvers are used to manage satellite along-track temporal separation to within 2–10 minutes between adjacent satellite to record the electrojet temporal evolution without the need for on-board propulsion. The combination of the sensing technique, compact instrument and Cubesat technologies allow EZIE to cost-effectively obtain never-before “mesoscale” measurements needed to understand how the solar wind energies stored in the magnetosphere are transferred to the thermosphere and ionosphere.  In this paper, we will present the current status of the EZIE mission and a summary of the measurement products and its latest results.