Scientists have discovered a distinct “switch-off” stage in the solar cycle that could enable forecasts of solar activity up to seven years before peak intensity, improving preparedness for space weather impacts.
- A sudden "switch-off" ends the Sun’s most violent space weather within each cycle.
- Sunspot numbers at this point help predict the intensity of the next solar cycle.
- Solar Cycle 26 is projected to be moderate, similar or slightly weaker than Cycle 25.
What happened
Scientists have pinpointed a specific moment in the Sun’s approximately 11-year activity cycle when the most extreme space weather abruptly ceases. This discovery marks a significant advance in solar forecasting because counting sunspots at this "switch-off" stage reveals the expected strength of the following solar cycle years in advance.
The research team has applied this method to Solar Cycle 26, predicting it will be moderate in intensity with a sunspot number estimated between 100 and 120. While this estimate is earlier than previous techniques could offer, a more precise forecast will emerge in about two years when Solar Cycle 25 reaches the distinct switching point, enabling observation-based predictions.
Why it feels good
This breakthrough offers practical benefits in anticipating solar activity that can disrupt communication, navigation systems, satellites, and power infrastructure on Earth. Knowing about solar storm severity several years early enhances preparedness and mitigates risks associated with space weather.
The method also deepens understanding of the solar dynamo, the process generating the Sun’s magnetic field, by indicating when the magnetic forces shaping the next cycle become established. This contributes valuable knowledge to space science and long-term forecasting reliability.
What to enjoy or watch next
In the coming two years, scientists will closely monitor Solar Cycle 25 as it approaches the "switch-off" point, which will refine predictions for Cycle 26’s peak activity. This period will be pivotal for confirming early estimates and potentially tuning forecasting methods for future cycles.
Meanwhile, enthusiasts can appreciate how recent solar storms produced spectacular aurora displays worldwide, including historic events in the UK in 2024 during Solar Cycle 25’s peak. Tracking upcoming solar activity offers exciting opportunities to observe natural space weather phenomena and understand their impact on everyday technology.