Recent research has unveiled distinct patterns in the particles ejected from the Sun, providing new insights into solar phenomena. A team of scientists, led by Alexander Warmuth from the Leibniz Institute for Astrophysics Potsdam (AIP) in Germany, analyzed data collected by the Solar Orbiter, a spacecraft developed by the European Space Agency (ESA). Their findings reveal that solar flares and coronal mass ejections (CMEs) produce particles with unique characteristics, hinting at their origins and behaviors.
The study, which focused on over 300 solar energetic electron (SEE) events between 2020 and 2022, highlights a clear differentiation between two types of particle emissions. According to Warmuth, “We see a clear split between ‘impulsive’ particle events, where these energetic electrons speed off the Sun’s surface in bursts via solar flares, and ‘gradual’ ones associated with more extended CMEs.” The gradual emissions release a wider array of particles over longer periods and broader angular ranges, providing a richer understanding of solar activity.
Using data from the Solar Orbiter, which approaches the Sun to within 42 million kilometers, the researchers were able to measure the particles in a pristine state. “By going so close to our star, we were able to measure the particles in a pristine state and could thus accurately determine the time and place where they started at the Sun,” Warmuth explained. This proximity enabled the team to uncover details about the source events of these particles, marking a significant advancement in solar research.
The connection between particles in space and their originating solar events has never been so clearly established. Co-author Frederic Schuller remarked, “It’s the first time we’ve clearly seen this connection between particles in space and their source events taking place at the Sun.” The Solar Orbiter’s instruments not only captured the SEE emissions but also monitored solar activity concurrently, enriching the data set and enhancing the team’s understanding of solar dynamics.
One notable finding pertains to the behavior of energetic electrons as they travel through space. Co-author Laura Rodríguez-García noted that confusing delays between the visual indicators of solar flares and the detection of radio bursts are related to the turbulent environment the particles encounter. “The electrons encounter turbulence, get scattered in different directions, and so on, so we don’t spot them immediately,” she said. This revelation clarifies that the lag is not due to a delay in the release of particles, but rather in their detection as they travel away from the Sun.
The insights gained from the Solar Orbiter are expected to contribute significantly to our understanding of solar activity and its implications for space exploration. Daniel Müller, ESA project scientist for the Solar Orbiter, emphasized the importance of this research, stating, “Knowledge such as this from Solar Orbiter will help protect other spacecraft in the future, by letting us better understand the energetic particles from the Sun that threaten our astronauts and satellites.”
The comprehensive analysis produced by this study, published in the journal Astronomy & Astrophysics, represents a milestone in solar physics, revealing the intricate processes occurring in our solar system’s most energetic environment. As the Solar Orbiter continues its mission, researchers anticipate further discoveries that will deepen our understanding of the Sun’s behavior and its effects on the solar system.
