A new analysis of data from NASA’s Parker Solar Probe shows that protons and heavy ions react differently to solar magnetic reconnection events, suggesting a more intricate mechanism behind space weather.
NASA’s Parker Solar Probe approaching the Sun. Image credit: NASA’s Scientific Visualization Studio.
Magnetic reconnection converts magnetic energy into explosive kinetic energy, powering solar events and causing space weather that impacts Earth.
This mechanism energizes protons and heavy ions, sending them shooting out from the Sun at high speeds.
Current models assume all these particles react the same way, but the new Parker Solar Probe data show distinct differences in particle acceleration.
While heavy ions shoot out straight like a laser beam, protons create waves that scatter subsequent particles in a dispersed pattern, more like a flashlight.
“The new data rewrite our understanding of reconnection,” said Dr. Mihir Desai, a researcher at the Southwest Research Institute and the University of Texas at San Antonio.
“Protons and heavy ions show distinct spectra that contradict current models.”
“Protons generate waves that scatter them more efficiently, while the heavy ions stay beam-like and retain their accelerated spectral shapes.”
“Magnetic reconnection is a ubiquitous phenomenon in the Universe, where magnetic field lines converge, break apart and reconnect.”
“At the Sun, the explosive physical process energizes particles and generates high-speed flows, driving space weather events such as solar flares and coronal mass ejections.”
“Space weather drives disturbances in Earth’s space environment, producing spectacular aurorae but can also disrupt operations of electrical power grids, satellite-based communication and navigation systems.”
“Understanding how magnetic reconnection works is critical for predicting hazardous events and protecting life and technological assets on Earth and in space.”
“What we are learning is that the Sun’s ‘magnetic engine’ is far more complex than we imagined,” Dr. Desai said.
“This is incredibly exciting because it demonstrates that our own star acts as a local, accessible laboratory for the same high-energy physics — like particle acceleration and magnetic snapping — that powers the most violent and mysterious phenomena in the Universe, from black holes to supernovae.”
The results were published March 31 in the Astrophysical Journal Letters.
_____
M.I. Desai et al. 2026. Proton and Heavy Ion Acceleration by Magnetic Reconnection at the Near-Sun Heliospheric Current Sheet. ApJ 1000, 300; doi: 10.3847/1538-4357/ae48f2
