Removing spacecraft-generated disturbances from the BepiColombo magnetic field data

In order to be useful for scientific analysis, the raw magnetic field data delivered by the BepiColombo Planetary Magnetometer must first be cleaned from stray magnetic fields originating from the spacecraft itself. This is especially important during the cruise phase, when the magnetic field instrument is still in the stowed position, close to various artificial magnetic field sources. The method we employ to remove these disturbances is a further development of the Maximum Variance Gradiometer technique already in use for cleaning the magnetic field data measured by the GeoKompsat-2A geostationary satellite. The main improvement over the above mentioned technique is the use of an intermediate non-orthogonal reference system which allows for decoupling of multiple disturbances. Here we describe the method and present the results of its application to the last Mercury flyby.