Colin Dickey writing for Aeon on why it’s dangerous for modern civilization to be so dependent on technology:

On 1 September 1859, the British astronomer Richard Carrington witnessed a Coronal Mass Ejection (CME), a burst of solar winds and magnetic energy that had escaped the corona of the Sun. The Carrington Event, as it came to be known, was not only the first recorded CME, it was also one of the largest ever on record, and it unleashed a foreboding and wondrous display of light and magnetic effects. Auroras were seen as far south in the northern hemisphere as San Salvador and Honolulu. As the Baltimore Sun reported at the time: ‘From twilight until 10 o’clock last night the whole heavens were lighted by the aurora borealis, more brilliant and beautiful than had been witnessed for years before.’

At the time, the event caused some minor magnetic disruption to telegraph wires, but for the most part there was little damage caused by such a spectacular event, its main legacy being the fantastic displays of light across the sky in early September. But should a solar flare happen on the scale of the Carrington Event now (and there’s a 12 per cent chance of one hitting the Earth before 2022), the effects might have a radically different impact on our advanced civilisation. If a CME with the same intensity were to hit the Earth head-on, it could cause catastrophic damage.

A National Research Council report in 2008 estimated that another Carrington Event could lead to a disruption of US infrastructure that could take between four and 10 years – and trillions of dollars – to recover from. Particularly vulnerable are the massive transformers on which our entire power system relies. Massive fluxes in magnetic energy can easily overload a transformer’s magnetic core, leading to overheating and melting of their copper cores. In the worst-case scenario, a repeat of the Carrington Event would cripple our infrastructure so severely it could lead to an apocalyptic breakdown of society, a threat utterly unknown to our ‘less civilised’ ancestors.