Swarm's absolute magnetometer experimental vector mode, an innovative capability for space magnetometry

ESA's Swarm satellites carry a new generation of 4He absolute magnetometers (ASM), designed by CEA-Leti and developed in partnership with CNES. These instruments are the rst-ever space-born magnetometers to use a common sensor to simultaneously deliver 1Hz independent absolute scalar and vector readings of the magnetic eld. Since launch, these ASMs provided very high accuracy scalar eld data, as nominally required for the mission, together with experimental vector eld data. Here, we compare geomagnetic eld models built from such ASM-only data with models built from the mission's nominal 1Hz data, combining ASM scalar data with independent uxgate magnetometer vector data. The high level of agreement between these models demonstrates the potential of the ASM's vector mode for data quality control and as a stand alone magnetometer, and illustrates the way the evolution of key eld features can easily be monitored from space with such absolute vector magnetometers.