Solar storms batter Earth every year, creating the occasional aurora and sometimes even paralyzing power grids. But these common phenomena pale in comparison to a monstrous event that inundated the planet with particles from the Sun around 14,300 years ago, identified as the strongest solar storm ever recorded in a recent study.
The study, published in Earth and Planetary Science Letters, has shed light on the extreme solar particle event that Earth experienced in 12,350 B.C.E. Such extreme events have only occurred a handful of times throughout history, and this is the first time one has been observed before the Holocene, around the end of the last Ice Age.
The Impacts of Solar Storms
Occasionally, the Sun launches a burst of accelerated particles into space, prompting what is called a solar particle event. These are often too weak to have considerable impacts here on Earth, although stronger events can pierce the planet’s magnetic field and disrupt technological systems.
Extreme solar particle events (ESPEs), however, are in a class of their own. Only eight of these events have been identified during the Holocene (the current epoch, ongoing for almost 12,000 years) — notable storms took place around 994 A.D., 663 B.C.E., 5259 B.C.E., and 7176 B.C.E.
A separate 2024 study states that ESPEs are “up to three orders of magnitude stronger than” any solar particle event that has been observed directly by satellites in the modern age. The same study predicts that if an ESPE were to hit Earth during a period when its magnetic field is weakened, it could cause DNA damage in humans and impair aquatic ecosystems.
Read More: Solar Flares are Stunning but are They Dangerous? Here's What to Know
Measuring the Strongest Solar Storm
The ESPE that occurred in 12,350 B.C.E. takes the word “extreme” to a new level, having been much stronger than solar storms that followed in the Holocene.
“Compared to the largest event of the modern satellite era — the 2005 particle storm — the ancient 12,350 B.C.E. event was over 500 times more intense, according to our estimates,” said Kseniia Golubenko, a postdoctoral researcher at the University of Oulu in Finland, in a statement.
The researchers gleaned the details of this storm — including its strength, timing, and terrestrial effects — through a model they developed, called SOCOL:14C-Ex. The data used to assess the 12,350 B.C.E. event comes from a radiocarbon deposit in a tree from Southwestern Europe; tree rings act like records for solar particle storms, preserving radiocarbon spikes in the atmosphere (called Miyake events) that were once caused by ESPEs.
The model was first tested on an ESPE that occurred around 775 A.D., the previous titleholder of the strongest solar storm. It then determined the intensity of the 12,350 B.C.E. event, confirming that it was 18 percent stronger than the 775 A.D. event.
Preparing for Solar Storms
The newly developed model has allowed researchers to better understand radiocarbon data in ancient glacial conditions, different from the relatively stable and warm conditions of the Holocene.
In the present day, we likely won’t have to worry about an ESPE as intense as the 12,350 B.C.E. event in our lifetime; less intense, yet still formidable solar storms are still a cause for concern, however. For example, the Gannon solar storm that hit Earth in May 2024 caused a series of short-lived communication and navigation problems.
Although the current solar cycle reached its peak near the end of 2024 (meaning an overall decline in solar activity is soon to follow), scientists are still determined to improve solar storm predictions. Details surrounding the 12,350 B.C.E. event may even assist preparation efforts in the future.
“This event establishes a new worst-case scenario,” said Golubenko. “Understanding its scale is critical for evaluating the risks posed by future solar storms to modern infrastructure like satellites, power grids, and communication systems.”
Read More: Violent Solar Storms Can Rage in the Universe About Every 100 Years
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
Earth and Planetary Science Letters. New SOCOL:14C-Ex model reveals that the Late-Glacial radiocarbon spike in 12350 BC was caused by the record-strong extreme solar storm
PNAS. Global impacts of an extreme solar particle event under different geomagnetic field strengths
NASA. What NASA Is Learning from the Biggest Geomagnetic Storm in 20 Years
Jack Knudson is an assistant editor at Discover with a strong interest in environmental science and history. Before joining Discover in 2023, he studied journalism at the Scripps College of Communication at Ohio University and previously interned at Recycling Today magazine.
