The European Space Agency’s Solar Orbiter spacecraft has made a landmark discovery, identifying the dual sources of energetic electrons flung from the Sun at nearly the speed of light. These Solar Energetic Electrons (SEEs) play a crucial role in space weather phenomena that can impact spacecraft, astronaut safety, and terrestrial technologies.
Coronal Mass Ejections Analyzed
By observing over 300 SEE events between 2020 and 2022, Solar Orbiter revealed two main categories of these electrons. The first arises from ‘impulsive’ bursts linked to intense solar flares—small but powerful explosions on the Sun’s surface. The second originates from ‘gradual’ emissions accompanying larger coronal mass ejections (CMEs), which throw out extensive swaths of hot gas and magnetic fields from the solar atmosphere. The CME-related events tend to release particles over a longer period and pose greater risks to technological assets in space.
Risk Mitigation for Spacecraft
This newfound clarity allows scientists to better predict space weather events. Understanding the type and timing of energetic particle releases enables improved forecasting models, key to protecting satellites, space missions, and critical infrastructure on Earth. The mission’s findings lay groundwork for future ESA projects like Vigil, launching in 2031, which will provide early warnings of solar storms from the Sun’s ‘far side’.
Science Community Reacts
Scientists worldwide have praised the mission’s detailed mapping of how energetic electrons form and travel from the Sun. Solar Orbiter’s ability to measure particles close to their source marks a technological and scientific triumph, pushing the boundaries of heliophysics. The data collected will continue to aid researchers and improve our understanding of the Sun-Earth connection for years to come.
