Key Takeaways on the Carrington Event:
A massive solar flare, followed by a series of coronal mass ejections, caused the Carrington Event, which happened on September 1, 1859.
The event disrupted global telegraph systems and caused auroras visible near the equator. If a solar event of this magnitude happened today, it would damage satellites, power grids, and communication’s networks.
The solar event was named after Richard Carrington, and it remains the most intense geomagnetic storm ever recorded.
On September 1, 1859, Richard Carrington, an English amateur astronomer, witnessed an explosion of light from the sun while observing sunspots. He described the incident as “a singular outbreak of light which lasted about five minutes," according to this study.
This massive solar event set off the largest geomagnetic storm ever recorded in recent times, now widely known as the Carrington Event. Within roughly 18 hours, billions of particles emitted from the sun struck the Earth, sending navigation devices haywire and disrupting telegram systems. Spectacular auroras could be seen in both hemispheres, even in the tropics.
Carrington had witnessed the first observed solar flare, and it was also an atypical one, says Martin Connors, professor of astronomy, mathematics, and physics at Athabasca University.
“Many people think that a solar flare, like the Carrington Event, is a visible thing that happens on the sun,” Connors says. “Most of them do not produce much visible light. So, this was an unusual event, and a large event.”
Why the Carrington Event Happened
The Carrington Event’s likely cause was a massive solar flare followed by a series of coronal mass ejections. These ejections fired billions of tons of magnetized plasma particles and radiation towards the Earth. When colliding with our planet’s magnetic field, these plasma clouds sparked a geomagnetic storm.
At the time of the Carrington Event, most people would not have had any major disruption to their life, says Connors, unless you were a telegraph operator. The event sparked electrical currents that shocked some operators and caused fires in some offices.
That wouldn’t be the case today as an event of this size could potentially damage satellites, power grids, and communication’s networks.
“The effects are on electromagnetic systems, and that's basically what our whole life is now, as opposed to back then,” says Connors.
Read More: The Strongest Solar Storm in History Impacted Earth 14,300 Years Ago
Could a Carrington-Level Storm Happen Today?
Such events can coalesce with the solar maximum during the 11-year solar cycle. At the solar maximum, the number of sunspots – cooler patches that are caused by intense concentrations of magnetic field lines – increases. For Earth, this can mean particularly strong and beautiful auroras around this time. But that doesn’t mean these massive solar events occur on a regular basis, as they remain rare.
Researchers have looked to the rings of trees and ice cores to trace the history of Earth’s collisions with the sun’s stormy activity. Connors points to evidence of other solar storms known as Miyake events, named after the scientist who made the initial discovery of a superflare from the 8th century.
That incident in 774 A.D. to 75 A.D. dwarfed the Carrington Event as it was at least 10 times stronger. Researchers have identified seven similar events over the past 15,000 years. Scientists found evidence of the largest solar storm ever recorded in tree samples in the French Alps, that dated back roughly 14,300 years ago. Another research paper published in 2022 suggests that these “strong solar events” could happen every 400 to 2,400 years.
Other research based on observations of other sun-like stars in the vastness of space indicates that large superflares, far larger than the Carrington Event, may occur every few hundred years or so.
“You can't really say that it's due,” says Connors, but adds that on average time scales, “we're probably going to get something sometime within the next 100 years.”
Read More: Solar Flares are Stunning but are They Dangerous? Here's What to Know
What a Carrington Event Would Do Today
That said, there is little agreement on the likelihood of another Carrington-scale solar flare within the next hundred years. Some researchers estimate the chances at less than 0.1 percent while others have stated 25 percent and other numbers in between.
“On Earth, as a single planet around a single sun, it's hard to assess the rare things that our Sun does,” says Connors. “What we're trying to do is gather information that allows us to predict these events. There's a large range of uncertainty, and that is why more research is necessary.”
“They are rare events. No question about that,” he adds. “But the question is how rare?”
What is certain is that if such an event were to occur, present day technology is much more vulnerable than in the 19th century. “Because of the development of our society, such events could be more devastating than they used to be. That's a certainty,” Connors adds. “We're much more vulnerable now."
Read More: Violent Solar Storms Can Rage in the Universe About Every 100 Years
Other Geomagnetic Storms
Since the Carrington Event, smaller geomagnetic storms have occurred. One such incident in 1989 caused a blackout for around nine-hours in Quebec, Canada. That was caused by two coronal mass ejections resulting in a magnetic storm. Earth had a lucky escape in 2012 when a “extreme solar storm” – thought to be as powerful as the Carrington Event – narrowly missed our planet.
As devastating as the consequences of a repeat of the Carrington Event could be today, Connors also emphasizes “not to go to bed and lie awake all night worrying about it.”
“These are rare events, and unfortunately, the consequences can be large,” he says. “We have to trust that our public officials are going to take them adequately into account and listen to the scientists.”
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
Advances in Space Research. The grand aurorae borealis seen in Colombia in 1859
National Oceanic and Atmospheric Administration. Five historically huge solar events
NASA. Sunspots
The Royal Society Publishing. Modelling cosmic radiation events in the tree-ring radiocarbon record
Forestry Engineering Journal. Miyake events: a review of the state-of-the-art
University of Leeds. Researchers identify largest ever solar storm in tree rings
Nature. Tree-rings reveal two strong solar proton events in 7176 and 5259 BCE
Advancing Earth and Space Sciences. A 21st Century View of the March 1989 Magnetic Storm
Sean Mowbray is a freelance writer based in Scotland. He covers the environment, archaeology, and general science topics. His work has also appeared in outlets such as Mongabay, New Scientist, Hakai Magazine, Ancient History Magazine, and others.
