The solar storm, which happened on July 23, 2012, was the strongest one ever recorded -- more than twice as powerful as any solar storm recorded in the last 15o years. "If it had hit, we would still be picking up the pieces," Daniel Baker of the University of Colorado said in a statement released by NASA this week. Play it 
 
 Baker, along with colleagues from NASA and other universities, published a seminal study of the storm in the December 2013 issue of the journal Space Weather. Storms have two components: large areas of violent activity called coronal mass ejections (CMEs) that are somewhat analogous to hurricanes; and powerful, focused high-speed solar flares you might think of as the solar equivalent of a tornado. The NASA spacecraft STEREO-A was able to withstand a full blast of solar radiation near the sun without harm. Baker told NASA, "I have come away from our recent studies more convinced than ever that Earth and its inhabitants were incredibly fortunate that the 2012 eruption happened when it did ... "If the eruption had occurred only one week earlier, Earth would have been in the line of fire. Solar storms do not pose a physical threat to people or animals or plants, just to our way of life. Sunspots and solar flares lead a few hours later to a bright display of the Northern Lights. In a large solar storm, the same energy from the corona can also cause a coronal mass ejection — a much slower-moving billion-ton cloud of plasma (electrons and protons). Analysts believe that a direct hit by an extreme CME such as the one that missed Earth in July 2012 could cause widespread power blackouts, disabling everything that plugs into a wall socket. Intense geomagnetic storms ignited Northern Lights as far south as Cuba and caused global telegraph lines to spark, setting fire to some telegraph offices and thus disabling the 'Victorian Internet." If we had been in its path, NASA says it would have had a "catastrophic effect," blowing out electrical systems, GPS, radio systems and other technology worldwide, plunging billions of people into a blackout that could take years to repair. The U.S. National Academy of Sciences convened a workshop in 2008 to address the question: "Are our institutions prepared to cope with the effects of a 'space weather Katrina,' a rare, but according to the historical record, not inconceivable eventuality?" Multi-ton transformers damaged by such a storm might take years to repair. “In my view the July 2012 storm was in all respects at least as strong as the 1859 Carrington event,” says Daniel Baker of the University of Colorado. “The only difference is, it missed.” [Read: Finally confirmed: An asteroid wiped out the dinosaurs.] In the February 2014 edition of Space Weather, physicist Pete Riley of Predictive Science Inc. warned that the odds of a serious geomagnetic storm hitting Earth in the next ten years was 12 percent. By extrapolating the frequency of ordinary storms to the extreme, he calculated the odds that a Carrington-class storm would hit Earth in the next ten years. Riley told NASA, "Initially, I was quite surprised that the odds were so high, but the statistics appear to be correct. "It is a sobering figure." Earth 's magnetic field deflects solar particles to a certain extent, but the strength of the Earth's magnetic field is decreasing, affording us less protection decade by decade. The worst geomagnetic storm of the Space Age, which knocked out power across Quebec in March 1989, registered Dst=-600 nT. Prior to the July 2012 event, the most powerful known solar storm, in 1859, was estimated at -800 nT to -1750 nT, although modern measurement techniques were not available then. "If that CME had hit Earth, the resulting geomagnetic storm would have registered a Dst of -1200, comparable to the Carrington Event and twice as bad as the March 1989 Quebec blackout." The reason researchers know so much about the July 2012 storm is because, out of all the spacecraft in the solar system it could have hit, it did hit a solar observatory. A common question about this event is, how did the STEREO-A probe survive?
– Imagine life without electricity or running water, and you'll understand what nearly befell our planet two years ago. Scientists say that on July 23, 2012, the sun belched its biggest solar flare in more than 150 years and barely missed us, CBS News reports. A week earlier and the storm would have struck Earth on its orbit with "catastrophic" effects, NASA says, blacking out radios, damaging satellite communications and GPS, and "disabling everything that plugs into a wall socket." Such a flare wouldn't hurt human life directly, and the Southern and Northern Lights would be gorgeous, but the blast's mix of X-rays, extreme UV radiation, energetic particles, and massive clouds of magnetized plasma would cause an estimated $2 trillion in damage. It would also leave "large parts of society" crippled for months or years while workers replaced major transformers and substations, ExtremeTech reports. The sun, on an 11-year solar-storm cycle, has nearly done this before: A massive storm called the "Carrington Event" struck Earth in 1859 but couldn't inflict much electrical damage in the age of steam engines (telegraph lines did spark and set fire), and a pretty powerful storm caused blackouts across Quebec in 1989. One physicist says there's a 12% chance of a big solar blast hitting us over the next decade, which he calls a "sobering figure." Another is quoted in the Guardian saying how lucky we are that the blast wasn't in sync with our orbit: "Earth and its inhabitants were incredibly fortunate that the 2012 eruption happened when it did," he says. "We'd still be picking up the pieces." (Read about the sun's newly discovered "long-lost brother.")