Today just about everything we use relies on electricity to operate from our smartphones and computers to our toilets in some cases. On July 23, 2012, the sun threw two gigantic clouds of plasma into space and they barely missed the Earth. In fact, had the coronal mass ejections happened only a week before, they could have devastated life on Earth according to scientists.
These storms wouldn't have killed people necessarily, but they would have likely damaged satellites and the electrical grid to the point that anything that plugs into the wall wouldn't have worked. Physicist Daniel Baker says that if those solar eruptions had hit the Earth, we would still be picking up the pieces two years later.
NASA said, "Analysts believe that a direct hit ... could cause widespread power blackouts, disabling everything that plugs into a wall socket. Most people wouldn't even be able to flush their toilet because urban water supplies largely rely on electric pumps. According to a study by the National Academy of Sciences, the total economic impact could exceed $2 trillion or 20 times greater than the costs of a Hurricane Katrina. Multi-ton transformers damaged by such a storm might take years to repair."