schwit1 writes: On July 23, 2012, the sun unleashed two massive clouds of plasma that barely missed a catastrophic encounter with the Earth's atmosphere. These plasma clouds, known as coronal mass ejections (CMEs), comprised a solar storm thought to be the most powerful in at least 150 years.
"If it had hit, we would still be picking up the pieces," physicist Daniel Baker of the University of Colorado tells NASA. Fortunately, the blast site of the CMEs was not directed at Earth. Had this event occurred a week earlier when the point of eruption was Earth-facing, a potentially disastrous outcome would have unfolded.
"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." Steve Tracton put it this way in his frightening overview of the risks of a severe solar storm: "The consequences could be devastating for commerce, transportation, agriculture and food stocks, fuel and water supplies, human health and medical facilities, national security, and daily life in general."