Sunspot prompts solar flare, which causes Earth's magnetic field to shift. If the magnetic field shifts quickly enough, the mine's detonator circuit thinks there's a large body of metal (ie a ship) moving past it, and blammo.
And it doesn't matter where the mine is, which is to say what depth it's positioned at. Interesting.
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Dumbass. If the bridge is up, stay away. Moron had to be taken away in an ambulance.
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WTF. The face of antifa.
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Cold outside. Barely above freezing today.