Swarm After 12 Years in Orbit: Mission Status, Instrument Performance, and Data Quality

Launched by the European Space Agency (ESA) in November 2013, the three-satellite Swarm constellation continues to deliver high-quality measurements of Earth’s magnetic field and the surrounding plasma environment. After more than 12 years in orbit, the mission has achieved remarkable scientific results, deepening our understanding of geomagnetic field dynamics and supporting applications that go well beyond the mission’s original goals.Equipped with 7 complementary instruments each spacecraft — including a Vector Field and an Absolute Scalar Magnetometer (VFM and ASM); star trackers (STR); a dual-frequency GPS receiver (GPSR); an accelerometer (ACC); an Electric Field Instrument (EFI), composed of two Langmuir Probes (LPs) and two Thermal Ion Imagers (TIIs) — Swarm has become a pivotal reference for geophysical research, supporting advances in areas such as core dynamics, ionospheric and magnetospheric processes, space weather monitoring, and the characterization of electric currents throughout the Geospace environment.This paper presents a comprehensive overview of the current status of the Swarm mission and constellation, with particular focus on the long-term performance, stability, and calibration of its instruments. The discussion highlights how the constellation’s unique configuration and consistently high data quality have ensured the continuity and reliability of key geophysical observations for more than a decade, with a look at plans for the next future of the mission.Furthermore, we outline the significant enhancements introduced with the latest Swarm data-processing baseline, which improves the accuracy, consistency, and overall usability of the mission’s data products.