Sunny surprise The worst thing our Sun can do against us isn't the heat, but the solar storms. Apparently the worst case of a solar storm was back in 1859 - the Carrington Event. The only high tech humanity had back then were the telegraph networks - and they were fried, together with some telegraph operators. Apparently the Earth's magnetosphere can't protect us from the solar superstorms, given what happened in 1859. Magnetosphere was overloaded, and did nothing.