Scientists have re-dated a famous 1841 railway disruption to 1848, solving a long-standing space weather mystery. Researchers found that an October 1841 train delay in Exeter, UK, blamed on a geomagnetic storm, was likely a typographical error in a 1998 paper. \n\nThe team, led by Wild, examined archival magnetograms from the Greenwich magnetic observatory in London. While extraordinary magnetic field records exist for 1840, no unusual auroral activity was reported in England for October 1841.

However, strong geomagnetic activity occurred around October 18, 1848, confirmed in contemporary newspapers and sunspot observations by Temple Chevallier. \n\nRailway timetables from 1848–1849 show a 10:05 pm express train from Exeter, matching the event. The authors suggest the 1841 date was a typo. The earliest confirmed space weather impact on technology remains a March 1847 incident where aurora disrupted Midland Railway telegraph systems.

The study is published in *Space Weather*, 2026.