ESA Simulates Historic Solar Storm to improve Satellite Resilience and Space Safety

At the European Space Agency’s (ESA) mission control in Darmstadt, Germany, teams recently engaged in a groundbreaking simulation meant to prepare for the rarest and most severe of space weather events. While these scenarios are usually hypothetical, the exercise recreated the potential fallout from a historic solar storm, one akin to the Carrington Event of 1859, which remains the most powerful geomagnetic storm recorded.

With the Sentinel-1D satellite set to launch on November 4, 2025, the ESA mission teams have been conducting rigorous exercises since mid-September to prepare for any possible anomalies during the initial moments of deployment. The simulations specifically aimed to test the resilience of satellite operations under extreme conditions, including a complete loss of satellite navigation and significant electronic disruptions.

“Facing an event of this nature presents significant challenges with no clear solutions. The primary objective is to maintain the safety of the satellite while minimizing potential damage,” said Thomas Ormston, the Deputy Spacecraft Operations Manager for Sentinel-1D. This simulation was particularly notable as it involved not only ESA’s Space Weather Office but also cooperation from the Space Debris Office and operators from other ESA missions, underscoring the interconnected nature of space safety.

The staged event began smoothly enough, with mission control receiving a successful signal from the satellite post-launch. However, the situation quickly turned when a massive solar flare struck, marked as an X45-class incident. The resulting electromagnetic wave reached Earth in just eight minutes, wreaking havoc on navigation systems, communications, and overall radar functionality. Ground stations, particularly those in polar regions, lost the ability to track satellites due to intense radiation.

As the scenario unfolded, operators scrambled to respond appropriately to the immediate threat of a coronal mass ejection (CME) that would follow. “The solar flare caught the team off guard, but they quickly regained focus, knowing they had only hours to prepare for the next wave of disturbance,” explained Gustavo Baldo Carvalho, the Lead Simulation Officer for Sentinel-1D.

Some 15 hours later, the CME hit, launching a torrent of hot plasma charged with particles at speeds up to 2000 km/s. This created a severe geomagnetic storm that not only produced spectacular auroras visible far from their usual range but also led to widespread damage to the electrical grid and heightened atmospheric drag on satellites in low Earth orbit, threatening their orbits and increasing collision risks.

The implications of such an event are far-reaching. “A storm of this magnitude could increase drag on satellites by as much as 400%, forcing operators to burn additional fuel to maintain their orbits and thus shortening their operational lifespan,” noted Jorge Amaya, ESA’s Space Weather Modelling Coordinator.

As radiation levels rose, satellite electronics became increasingly vulnerable, leading to system malfunctions and degraded GNSS signals. “An explosive event of this degree would pose risks to all satellites in orbit,” Amaya cautioned, highlighting the unpreparedness inherent in current systems.

The simulation not only served to prepare teams for possible real-life scenarios but also underscored a critical need for improvements in Europe’s ability to forecast and manage space weather risks effectively. ESA is advancing its Distributed Space Weather Sensor System (D3S), designed to monitor various space weather parameters and enhance early warning capabilities. Additionally, the planned Vigil mission, set to be launched in 2031, aims to observe solar activity from a unique vantage point, providing advanced alerts for potential solar threats.

“This exercise has provided us with valuable insights into how we can better plan and respond to extreme space weather events,” Vargas concluded. With a focus on improving resilience, ESA continues to pave the way for enhanced safety in the increasingly crowded frontier of space.