Protecting astronauts and satellites

Solar storms, and especially the high-energy particles they can produce, are a major concern for missions venturing beyond Earth’s magnetic shield. These particles are difficult to shield against and can dramatically increase radiation exposure, posing potential risks to astronaut health and spacecraft systems.

Several ESA and partner spacecraft carry radiation instruments designed within/for ESA programmes to diagnose anomalies, support operational decisions, and improve specification models informing spacecraft design. These instruments also help improve our understanding of heliophysics and space weather modelling. ESA is also developing next-generation technologies to reduce the cost, mass, and power consumption of these instruments while enhancing performance.

To minimise exposure, ESA and other space agencies apply the ALARA (as low as reasonably achievable) principle. During severe storms, this may involve measures such as postponing spacewalks, relocating astronauts to shielded areas when necessary and, in, extreme cases, delaying launches.

These measurements will be even more critical for future lunar and deep-space missions beyond Earth’s protective magnetic field. In this context, ESA is exploring new shielding strategies, studying how materials including planetary surface regolith like that of the Moon can influence radiation environments, and investigating the full range of biological effects from high-energy particles to better protect crews and systems.