Macau Scientific Satellite-1 Initial Magnetic Field Model

Eight months of vector magnetic field measurements from the Macau Scientific Satellite-1 (MSS-1), supplemented by higher latitude field intensity measurements from the Swarm satellites, are used to derive an MSS-1 Initial Field Model (MIFM). Robust root-meansquare misfits between MIFM and the three components of the MSS-1 vector data are found to be below 3.3 nT. MIFM agrees well with the CHAOS-7 field model and we find even better agreement with an identically parameterised model derived only from Swarm data. MSS-1 and Swarm vector data can moreover be fit simultaneously with only a small increase in misfit (by less than 0.2 nT). We show that both lithospheric anomalies and core surface field changes can be studied using MSS-1 data. With its fast coverage of local times MSS-1 is a valuable addition to the global geomagnetic observing system.