A solar storm caused a power failure in Quebec in 1989. Another solar flare apparently caused a power failure in New Zealand in 2001.
"The American Geophysical Union in Washington D.C. released a story yesterday suggesting the sun does have the capability of disrupting electrical systems on Earth – not just at high latitudes (near Earth’s poles) as happened in Québec in 1989 – but also at lower latitudes. How does the sun do this? The source of the potential disruption is solar flares, which are powerful releases of energy from the sun – and their subsequent coronal mass ejections (CMEs), which are massive burst of solar wind and magnetic fields released into space, sometimes headed Earth’s way.
We humans on Earth are at no danger from solar flares and CMEs. Earth’s atmosphere protects us, and, in fact, earthly life has evolved under the influence of these events for billions of year. But there’s been an increasing awareness that perhaps science should evaluate the potential impact of a flare event on earthly technologies, especially electric power grids."
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