How the Sun Almost Triggered A War
published during a waxing gibbous moon.


Credit: National Solar Observatory historical archive

In the corners of the Cold War stood the United States and the Soviet Union, husky contenders in a decades-long, antagonistic nuclear standoff. But this week a study unveiled another, stronger enemy that could have easily bopped the superpowers’ heads together: the sun.

It was the storm before an impending storm: On a spring day in 1967, the sun ejected a solar flare that walloped Earth’s atmosphere. Former U.S. Air Force officers revealed the classified event in a paper published in the American Geophysical Union’s journal Space Weather.



Solar flares are a looming cosmic threat and occur when the sun’s magnetic fields twist and snap, sending tons upon tons of charged particles into space. When that radiation hits our ionosphere, it can cause power outages or seriously mess with satellite-dependent activities, including radio.

As a result of the ’67 storm, communications got jammed — specifically, radars in Alaska, Greenland, and the United Kingdom that were meant to detect Soviet ballistic missiles. The early-warning sites, built earlier in the ‘60s, bought defense teams about 15 minutes of time.

The Air Force, under the impression that the Soviet Union was responsible for the blocked signals — an act of war — bristled at the overture and prepared more of its fleet.


But just in time, space weathermen delivered crucial news to commanders: It was a false alarm. A solar storm, not the Soviet Union, that was toying with the radars. The planes were grounded, and mutually assured annihilation was thwarted.

The military’s Air Weather Service started combing the skies for space weather in the late ‘50s, so by the time the storm hit, there was a network of observers reporting to solar forecasters at North American Aerospace Defense Command (NORAD).

NORAD also keeps an eye out for other explosions like coronal mass ejections, which can hurtle particles even faster than a solar flare. Though flares occur regularly, Earth has had some close calls in recent years.

Learn more about the sun’s elegant but terrifying swirls here.