schwit1 quotes a report from Space.com: A powerful solar storm nearly heated the Cold War up catastrophically a half century ago, a new study suggests. The U.S. Air Force began preparing for war on May 23, 1967, thinking that the Soviet Union had jammed a set of American surveillance radars. But military space-weather forecasters intervened in time, telling top officials that a powerful sun eruption was to blame, according to the study. "Had it not been for the fact that we had invested very early on in solar and geomagnetic storm observations and forecasting, the impact [of the storm] likely would have been much greater," Delores Knipp, a space physicist at the University of Colorado Boulder and the study's lead author, said in a statement. "This was a lesson learned in how important it is to be prepared." Initially, it was assumed that the Soviet Union was to blame. Since radar jamming is considered an act of war, "commanders quickly began preparing nuclear-weapon-equipped aircraft for launch." Spoiler: Solar forecasters at the North American Aerospace Defense Command (NORAD) figured out it was a flare that caused the outages, not the Soviets. You can read the abstract of the paper for free here.