The IMAP magnetometer (MAG) consists of a pair of identical triaxial fluxgate magnetometers based on the Magnetospheric Multiscale (MMS) magnetometers, for which UCLA built 4 electronics units and 9 fluxgate sensors. On IMAP, the magnetometers are both mounted on a 1.8 m boom to reduce the impact of the magnetometer on spacecraft design, and through gradiometry to reduce the effect of spacecraft magnetic fields on the measurements of the instrument by dynamically removing the spacecraft field. This technique was tested and proven valuable on the Venus Express mission with only a 1 m boom and no magnetic cleanliness program. Even the signals of the Venus Express spinning magnetic reaction wheels were removed. The gradiometer not only maintains an accurate baseline for space weather applications, but also allows new insight into waves and turbulence in the solar wind to frequencies near the electron gyrofrequency.
All schematics and numbers are preliminary as of the beginning of Phase A. Additional information about each instrument can be found in the Open Access IMAP Paper.