Sunspot 1158 has belched out two great blobs of electrically-charged gas, the first an M-class CME and the second an X-class. A sunspot back in 1859 known as the Carrington Event brought the Aurora Borealis down to tropical latitudes and caused telegraph equipment to burst into flames. (Aurora-induced currents in the wires even allowed messages to be transmitted after the batteries had been disconnected.) If we got one that big today, it could shut down all types of fragile things our civilization relies on – communications, GPS, power grids.
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