" #Strong #electrical currents were #surging through #rocks and #soil . The biggest voltages along the US eastern seaboard and in the Midwest were as much as 10,000 times normal.
...
Back in March 1989, voltages only a little stronger than the ones shown above #broughtdown the entire #HydroQuébec #powersystem. ..."

https://spaceweather.com/

#spaceweather #solarstorm #geomagnetic #geoelectric