Solar Physics ESA analyses impacts of November 2025 solar storm after three CMEs strike Earth

A sequence of three coronal mass ejections reached Earth in mid-November, triggering a severe six-hour geomagnetic storm during the current solar maximum. While the event disrupted radio communications across several continents, critical infrastructure and ESA spacecraft remained unaffected. Multiple missions collected radiation and plasma data now under analysis, offering new insights for future space-weather resilience.

Between 11 and 14 November 2025, an active solar region (NOAA AR 14274) released four solar flares and four coronal mass ejections, three of which were Earth-directed. The strongest eruption occurred on 11 November, when an intense X-class flare peaked at 10:04 UTC, followed by a CME initially estimated to travel at around 1,500 km/s. It struck Earth on 12 November at 18:50 UTC, producing a severe geomagnetic storm that lasted roughly six hours before declining to moderate levels.The storm caused major radio blackouts across Europe, Africa and Asia for 30–60 minutes. A rare Ground Level Enhancement (GLE) — only the 77th recorded since the 1940s — was observed when highly energetic particles penetrated Earth’s magnetic field. Despite the intensity, ESA reports no biological risk to people on Earth and no radiation-related damage to its spacecraft.

ESA missions capture radiation and magnetic effects

Several ESA satellites recorded signatures of the event in real time.

• The SMOS Earth observation mission detected a large solar radio burst 14 hours before storm onset, measuring a left-handed polarisation at 1.4 GHz.
   
• The Swarm constellation observed magnetic fluctuations up to ten times above normal, along with temporary proton enhancements producing diffuse “proton auroras” at high latitudes.
• At L1, the ESA/NASA SOHO mission captured the earliest imagery of the CMEs.
• Solar Orbiter recorded the X5 flare, particle environment and magnetic structures associated with the CME.
• BepiColombo, aligned with the Sun–Earth line, experienced one of its strongest solar energetic particle exposures since launch, reporting several transient memory errors that were resolved by onboard protections.

Implications for astronaut safety and deep-space exploration 

Although Earth’s magnetic field protected the surface from harmful radiation, the event illustrates the challenge of operating beyond low-Earth orbit. Energetic particles can impair spacecraft electronics and significantly increase radiation doses for astronauts. ESA and partner agencies apply the ALARA principle during severe storms, adjusting operations such as spacewalks, crew sheltering and launch schedules.Radiation instruments across ESA missions — developed to diagnose anomalies and refine environmental models — are crucial for future lunar and deep-space missions. Ongoing research includes shielding strategies, regolith-based protection concepts and biological impact studies to improve mission safety.

Preparing for the next generation of space-weather monitoring

The storm underscored the need for earlier and more accurate predictions. Current solar-wind monitoring from L1 gives operators roughly 20 minutes of warning. ESA’s Vigil mission, planned for launch in 2031, will observe solar activity from Lagrange Point L5, identifying hazardous events before they rotate into Earth view. A proposed L1-farther-out mission, SHIELD, could extend geomagnetic storm warnings to approximately 2.5 hours — a significant improvement for power grids and satellite operators.