The Solar Orbiter mission of the European Space Agency (ESA) has provided the first direct evidence of two different sources of solar energetic electrons (SEE) — particles capable of accelerating to nearly the speed of light. This breakthrough will improve forecasts of space weather, which affects satellite operations, communications, and astronaut safety.
According to lead author Alexander Warmuth of the Leibniz Institute for Astrophysics Potsdam, “We see a clear distinction between ‘impulsive’ events, where electrons are explosively released during solar flares, and ‘gradual’ events associated with coronal mass ejections.”
Solar Orbiter analyzed over 300 events between 2020 and 2022 using eight of its ten scientific instruments, establishing for the first time a direct connection between electrons observed in space and their sources on the Sun. The study also explains why electrons are often detected with a delay after flares: this is due to the specifics of their release and propagation through interplanetary space.
ESA mission scientist Daniel Müller emphasized the practical significance of the findings: “The knowledge gained from Solar Orbiter will help protect satellites and astronauts, as we now better understand the solar particles that pose a threat.”
Solar Orbiter’s discoveries also lay the groundwork for future missions:
- SMILE (launch in 2026) will study Earth’s magnetic field response to solar storms;
- Vigil (2031) will monitor the Sun from afar to provide early warnings of hazardous events.
In this way, Solar Orbiter has not only revealed the Sun’s “hidden engines” but also taken a step toward establishing an early warning system for space weather.
