A groundbreaking scientific discovery has revealed what is now considered the most powerful solar particle storm ever recorded—dating back approximately 14,300 years to 12,350 BCE. This extreme solar event, identified through ancient tree ring analysis, not only sheds light on our planet’s cosmic past but also raises important questions about future space weather risks.
A Solar Superstorm from the Ice Age
Led by Dr. Kseniia Golubenko and Professor Ilya Usoskin from the University of Oulu in Finland, the research team developed a new chemistry-climate model called SOCOL:14C-Ex to analyze cosmic events under Ice Age conditions. Their findings indicate that the ancient solar storm was about 18% stronger than the previously most powerful known event in 775 AD—and 500 times more intense than the strongest solar particle storm of the modern satellite era in 2005.
Tree Rings Reveal a Radiocarbon Time Stamp
Solar particle events dramatically increase the production of radiocarbon (¹⁴C) in Earth’s atmosphere. This spike becomes preserved in annual tree rings, leaving a clear cosmic time marker. The newly analyzed wood samples from the French Alps confirmed the scale and timing of the event, providing unprecedented accuracy in dating.
Redefining Solar Activity and Historical Chronologies
Such spikes, known as Miyake events, are named after the Japanese researcher who first identified them. These rare occurrences offer invaluable data not only for solar physics but also for archaeological dating. Thanks to these radiocarbon anomalies, scientists have been able to precisely date Viking settlements in Newfoundland and Neolithic communities in Greece.
Beyond the Holocene: A New Worst-Case Scenario
“This is the only known extreme solar particle event outside the Holocene,” notes Dr. Golubenko. The Holocene represents the last ~12,000 years of relatively stable climate, during which most known solar events occurred. This new discovery breaks that boundary, suggesting that even glacial periods are not immune to catastrophic solar activity.
Crucially, the magnitude of this event represents a new worst-case scenario for space weather planning. If such a storm occurred today, it could cause massive disruptions to satellites, power grids, and communication networks around the globe.
A Global Scientific Effort
The study, published in Earth and Planetary Science Letters, involved researchers from Finland, France, and Switzerland, and was led by Professor Edouard Bard of CEREGE in France. The work marks a major step forward in our understanding of solar extremes and how they interact with Earth’s atmosphere across different climatic eras.
Kseniia Golubenko et al, New SOCOL:14C-Ex model reveals that the Late-Glacial radiocarbon spike in 12350 BC was caused by the record-strong extreme solar storm, Earth and Planetary Science Letters (2025). DOI: 10.1016/j.epsl.2025.119383
