Solar storms could cause train delays

Solar storms could cause train delays

Solar flares and coronal mass ejections are possible culprits for train signalling glitches.

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Published: May 21, 2025 at 11:10 am

"Your train has been delayed due to a signalling failure" is a phrase commuters will be all too familiar with.

While most of us might lay the blame on snow or rain, there is a study that suggests another type of weather could also be at fault: space weather, in the form of ejections from the Sun interacting with Earth's magnetic field.

Train signalling systems use electric currents in the rails to determine if a train is present on a given section of track, showing a red light if it detects one.

    A red light indicates the presence of a train on the track, or could it be space weather interference? Photo by John Keeble/Getty Images)
    A red light indicates the presence of a train on the track, or could it be space weather interference? Photo by John Keeble/Getty Images)

    However, solar storms also cause similar currents to form in the rails and it only takes a moderate event to trigger a red signal, even when there’s no train present.

    "We are now working on looking at the case where trains are present on the line, and how strong a solar storm needs to be to turn a red signal back to green," says Cameron Patterson from Lancaster University, who investigated the phenomenon.

    "That’s a far more hazardous scenario, potentially leading to crashes!"

    www.lancaster.ac.uk

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