A 178-year-old mystery surrounding one of the earliest recorded examples of space weather affecting technology has been solved by an international research team.
As some of the first electric telegraph networks were built in the 1840s, telegraph operators began to experience unexplained electrical effects caused by disturbances in the earth’s magnetic field.
Now archival investigations led by Lancaster University with scientists from RMIT University, the British Geological Survey, Natural Resources Canada, Baylor University and the UK’s national space laboratory, RAL Space, have re-examined accounts of a train delayed almost two centuries ago in Exeter, England, when the sun’s energy disrupted the railway’s telegraph system.
What they found sheds new light on the earliest examples of space weather disrupting electric technology.
A brief history of solar weather disturbance ‘firsts’
A massive solar flare and coronal mass ejection in 1859, known as the Carrington Event, is one of the most famous early space weather events to affect technology.
It caused aurora borealis ‘northern lights’ as far south as Hawaii and Central America so bright that people could read newspapers by their light and gold miners mistook the glow for morning and began cooking breakfast shortly after midnight.
Telegraph systems worldwide failed, sparking lines gave electrical shocks to operators and even caught fire, and some systems even operated without batteries using only the geomagnetic current induced in the wires.
As some of the first electric telegraph networks were built in the 1840s, telegraph operators began to experience unexplained electrical effects caused by disturbances in the earth’s magnetic field.
Years later, in the 1870s, an anonymous author writing in Nature published a study about “very intense magnetic disturbance” on 18 October 1841, interfering with train signals and delaying the 10:05pm departure from Exeter by 16 minutes. The timing of this account places it as the earliest known example of space weather affecting human technology.
However, the timing of this event has now been debunked by the team’s study, just published in the American Geophysical Union journal Space Weather.
A ghost train and the truth uncovered
RMIT University space weather expert, Associate Professor Brett Carter, who investigated the archives to help the team uncover the truth, said they found one critical problem – the railway line referenced in the account did not open until 1846, almost five years after the alleged 1841 incident.
“In this study, we effectively investigated what had to be a typo in a Nature paper from 1871. We know it was a typo because the Exeter-to-Starcross train line mentioned in that paper didn’t exist until 1846, which is 5 years afterwards,” he said.
To uncover what really happened, the team combined evidence from railway timetables, historical newspapers, solar observations, auroral reports and digitised geomagnetic records.
Their investigation shows that the incident most likely took place on 18 October 1848, rather than 18 October 1841.
Carter says understanding the details of this period matters because it marked a crossing over point of no return in the inter-relationship between electronic technology and space weather.
“Understanding this historical event is important because the 1840s mark the intersection between the rise of our technological age and space weather, which has always been around,” Carter says.
“Since this line was crossed, humans have not looked back.”
The findings show that while the Exeter incident remains one of the earliest documented examples of space weather disrupting technology, it was not the first. The earliest credible report currently known is interference with telegraph systems on the Midland Railway in March 1847.
Space weather as a long-standing natural hazard
Study lead author, Professor Jim Wild from Lancaster University, said the study challenged notions that space weather is a modern challenge.
“What this research highlights is that space weather is not a new threat but a long-standing natural hazard. Society has been experiencing the effects of space weather on technology for almost as long as electrical technologies have existed,” Wild said.
“The Exeter train delay is a fascinating story because it sits right at the point where emerging technologies first began to encounter the realities of the space environment. By combining historical archives with scientific observations, we’ve been able to show that the event almost certainly happened in 1848 rather than 1841.
“Although this means it is not the earliest recorded space weather impact, it remains one of the first clear examples of solar activity disrupting critical infrastructure,” he said.
“It also demonstrates the value of combining scientific records with contemporary newspaper reports and archival documents when reconstructing historic space weather events.”
Dr Mike Hapgood, Visiting Scientist and space weather expert at the UK’s national space laboratory, RAL Space, said the study had felt like a detective story.
“It highlights the importance of preserving these older records, which give us the evidence base we need to interpret past events and strengthen future predictions,” he said.
Nearly two centuries later, railways and other critical infrastructure remain vulnerable to space weather, although through very different technologies including power systems, signalling equipment, satellite navigation and communications networks.
Hapgood said while today’s space weather capabilities are far more advanced than anything available in the 1800s, the modern technologies we depend on are also much more vulnerable to solar storms.
“Deepening our understanding of these events is essential for preparing for, and mitigating, the impacts of space weather – especially as we look forward to a decade of exciting space developments that will face the challenge of a new solar cycle in the 2030s,” he said.
The study ‘Did space weather delay the 10:05 p.m. train departure from Exeter on 18 October 1841?‘ Is published in Space Weather (DOI: 10.1029/2026SW005239).
