The IMAP magnetometer (MAG) consists of a pair of identical magnetometers which each measure the magnetic field in three directions in the vicinity of the spacecraft. The magnetometers are both mounted on a boom to minimize interference from the spacecraft; two sensors at different distances on the boom are used to help characterize the spacecraft signals.
 
MAG will contribute to our understanding of the acceleration and transport of charged particles in the heliosphere. Magnetic fields control how charged particles travel across the solar system, and they are also central to the processes that accelerate these particles, such as shocks and turbulence.
 
MAG will also provide measurements for the IMAP Active Link for Real-Time (I-ALiRT) space weather monitoring service. With I-ALiRT, IMAP will enable new ways of forecasting space weather by streaming real-time observations of conditions headed towards Earth to operators on the ground.
 
MAG design and assembly is led by Imperial College, London.