A Solar Flare Almost Sparked a Nuclear War in 1967

Aerial view of three radar stations at the Ballistic Missile Early Warning System in Anderson, Alaska, in 1962. Image: Wikimedia

by Maddie Stone – Gizmodo

On May 23rd, 1967, the United States Air Force scrambled to ready nuclear missile-laden aircraft for deployment. Radar systems designed to detect incoming Soviet missiles had just been disrupted, in what the military perceived to be an act of war. But before any nukes were launched in retaliation, it seems Air Force command was told to stand down.

Just in the nick of time, the United States’ newly minted Solar Forecasting Center was able to convey the true cause of the radar jamming: a rash of powerful solar flares. That’s according to a new military history paper, which reveals for the first time just how close humanity came to annihilating itself because of space weather.

“This is what we would characterize as a really near miss,” lead author Delores Knipp, a former Air Force officer and space weather physicist at the University of Colorado, Boulder, told Gizmodo.

Space weather is a catch-all term for a bunch of high-energy material the sun hurls our way during periods of heightened activity. It starts with a solar flare, which sends a burst of x-rays and ultraviolet light streaming off into space. When a flare strikes the upper portion of our atmosphere, called the ionosphere, it acts like an EM pulse, ripping electrons off atoms and building up tremendous electrical charge.

This can cause radio devices to go dead, as Thomas Berger, director of the Space Weather Prediction Center at NOAA, told Gizmodo last summer:

Radio communications are sometimes impacted. Over the horizon radio becomes difficult. When airplanes are flying over the poles, the only way they communicate with control centers is high frequency radio waves bouncing over the continents. But it’s just a temporary difficulty lasting ten minutes to hours at the most.

Following a major flare, the sun typically pops off a giant cloud of magnetized plasma, called a coronal mass ejection (CME). This slow-moving blob of starstuff can take from 12 hours to several days to reach the Earth, but it’s responsible for the most severe consequences of space weather, including the aurora borealis (northern lights) and widespread power blackouts….READ FULL ARTICLE