Scientists at the Aryabhatta Research Institute of Observational Sciences (ARIES), an autonomous institute under the Department of Science & Technology (DST), Government of India, have made a major breakthrough in understanding the origins of powerful solar eruptions that can disrupt satellites, power grids, and space missions.
Using advanced computational simulations, the team has identified two critical factors that determine whether a solar magnetic structure will erupt into space as a Coronal Mass Ejection (CME) — one of the primary drivers of geomagnetic storms on Earth.
The findings not only shed light on the physics of solar eruptions but also offer a promising pathway toward more accurate space weather forecasting.
The Sun’s ‘Magnetic Cage’ Controls Eruptions
The research, led by Nitin Vashishtha, PhD scholar, and Dr. Vaibhav Pant, Scientist at ARIES, employed sophisticated magnetohydrodynamic (MHD) simulations to recreate solar eruption scenarios using the widely accepted “breakout model” of CME initiation.
Their simulations reveal that the Sun’s global magnetic field acts like a magnetic cage, restraining eruptions.
When the background magnetic field was strong, the simulated CME struggled to escape and ultimately failed. However, when the background field was weaker, eruptions broke free successfully.
This result provides crucial insight into a long-standing solar mystery:
Although Solar Cycle 24 was magnetically weaker than Solar Cycle 23, it paradoxically produced a higher number of CMEs. The ARIES team’s simulations suggest that the weaker global magnetic field during Cycle 24 lowered the eruption threshold, allowing even relatively small magnetic disturbances to escape into space.
The Role of Magnetic Twist: Speed Matters
Beyond the restraining effect of the global field, the study uncovered a second decisive factor — the rate at which magnetic twist (helicity) builds up in the solar corona.
The researchers focused on a parameter called Absolute Net Current Helicity (ANCH), along with other magnetic indicators such as magnetic energy and Total Unsigned Current Helicity (TUCH).
Their results showed that the growth rate of ANCH, rather than just its total amount, is the most reliable indicator of an impending eruption.
-
A slow, gradual rise in ANCH resulted in failed eruptions, where magnetic structures formed but collapsed back to the solar surface.
-
A rapid, steep increase in ANCH consistently preceded successful CMEs.
-
In scenarios with the fastest ANCH injection, simulations produced multiple successive eruptions from the same region.
“Our findings indicate that among these parameters, the time rate of absolute net current helicity can serve as the most effective indicator for distinguishing between various eruption scenarios,” the researchers noted.
Toward Better Space Weather Forecasting
Geomagnetic storms triggered by CMEs can:
-
Disrupt satellite operations
-
Damage power grid infrastructure
-
Interfere with GPS and communication systems
-
Expose astronauts to harmful radiation
Accurate forecasting of such events remains one of the most pressing challenges in heliophysics.
Dr. Vaibhav Pant explained:
“These simulations act as our virtual laboratory for the Sun, allowing us to test the fundamental physics of these massive eruptions. The next frontier is to translate these findings, particularly the importance of the energy build-up rate, into a reliable tool for forecasting real-world space weather events and protecting our vital infrastructure.”
A Step Forward for Indian Space Science
By combining theoretical modelling with high-performance computational simulations, the ARIES team has strengthened India’s role in cutting-edge solar physics research.
The study enhances our understanding of how solar magnetic structures evolve and erupt — knowledge that is vital as humanity becomes increasingly dependent on space-based technologies.
The research has been published in a leading international astrophysics journal and is available at:https://doi.org/10.3847/1538-4357/adff54