Tiny Satellites to Explore Earth’s Magnetic Field

Our planet is enveloped by the Earth's magnetic field, a crucial shield generated by core movements that safeguards us from solar winds and cosmic rays. Despite its protective nature, this magnetic field is susceptible to various fluctuations stemming from multiple sources, including movements within the Earth's core, interactions with solar winds, tides, human activities, and more. During magnetic storms, instabilities caused by solar wind can result in disruptions in power grids, navigation systems, and heightened satellite exposure to ionizing particles.

The analysis of Earth's magnetic field holds significant importance across various sectors. Jean-Michel Léger, Head of the “Space Applications” program at CEA, highlights the scientific significance of this study. Understanding the planet and its evolution through the lens of its magnetic field can aid in magnetic navigation, as well as provide insights into ocean temperature and salinity.

Currently, the Earth's magnetic field is studied using ground magnetic observatories, magnetometers on aircraft, and the European Space Agency's (ESA) Swarm space mission. Swarm, launched in 2013, comprises three mini-satellites equipped with magnetometers developed by CEA-Leti. The insights gained from Swarm have paved the way for a new mission proposal.

In 2014, the NanoMagSat project was initiated by CEA-Leti and IPGP, with support from CNES. Successfully securing a three-year program with a budget of thirty million euros from ESA in 2019, the NanoMagSat mission involves three “16U Cubesat” nanosatellites, each weighing around 25 kg. These nanosatellites, equipped with miniaturized magnetometers, will enhance measurements compared to Swarm and provide valuable data on space weather.

Optimizing both instruments and constellation configuration, the NanoMagSat mission aims to improve space-time coverage by deploying two satellites in low orbit at a 60° inclination. Following a risk-reduction study in 2022, ESA approved the continuation of the project, setting the stage for the mission's commencement. With satellite launches scheduled for the end of 2027, the NanoMagSat consortium is gearing up for this exciting venture.