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Here’s what you’ll learn when you read this story:

In the fall of 1988, a U.S. spy plane recorded a strange light phenomenon—known as the “Dome of Light”—following the launch of a Soviet SS-20 Saber intermediate-range ballistic missile.

Initially, experts wondered if the fuel used for the rocket created the unexplainable aurora, or if it was an ion cloud of some sort.

A more accepted theory was that the Dome of Light was a countermeasure designed for overcoming anti-missile defenses in the U.S. and Europe.

If there’s one thing that the Soviet Union was good at, it was keeping secrets. The U.S.’s Cold War adversary gained valuable information through espionage efforts in order to develop its first atomic bomb in extreme secrecy, and the launch of Sputnik in 1957 similarly caught the world by surprise. It even took the world days to discern that something was terribly wrong after the meltdown of the Chernobyl nuclear power plant in 1986.

Because of the USSR’s predilection for concealment, the U.S. developed various ways to snoop on its rival— high-flying aircraft like the U-2 , innovative spy satellites , and deep-sea contraptions purpose-built to scoop up destroyed Soviet submarines from ocean’s watery depths. But the U.S. had another reconnaissance trick up its sleeve stationed at Shemya Air Force Base in the Aleutian Islands. The aircraft was known as the Boeing RC-135S Cobra Ball , which was a modified Boeing C-135 Stratolifter airframe (complete with an array of optical and electronic sensors) tricked out for just one mission in mind: tracking Soviet missile launches.

In the fall of 1988, U.S. Air Force pilot Robert Hopkins was on just such a mission. Nestled in the cockpit of the RC-135S Cobra Ball, he observed a missile launch that was part of a shoot-to-destruction provision in the 1987 Intermediate Nuclear Forces Treaty between the U.S. and the Soviet Union . The treaty allowed countries to dispose of now-illegal munitions by launching them to known impact sites, reported TWZ back in 2019 . The Soviet Union planned to fire a SS-20 Saber intermediate-range ballistic missile, and Hopkins and his copilot were on hand to observe, with instruments trained to gather speed and telemetry data.

But then something strange happened. As Hopkins told TWZ:

As we looked for traffic, we noticed what appeared to be a translucent, milky white wall moving from the left, over the USSR, to the right, toward the Northern Pacific Ocean . It covered the entire sky from ground level to as far up as we could see looking out the front windows of the airplane. It moved very quickly—far faster than crossing airplane traffic—and rapidly approached us. The wall of light passed across our flight path and then continued eastward, leaving the empty and dark night sky in its wake.

The ‘wall’ received the nickname “Dome of Light”—an unexplained phenomenon that Hopkins and the same co-pilot saw just one more time, also following an SS-20 missile launch. Initially, the pilots chalked up the experience to a hallucination or an “auroral event neither of us had ever seen,” Hopkins told TWZ. But Air Force scientists weren’t convinced. Was it possible that the SS-20 used a special fuel that caused this strange light, or was it perhaps a type of ion cloud for measuring aspects of the upper atmosphere ?

The more sinister explanation was that the Dome of Light was specifically designed as a countermeasure to confound U.S. and European anti-missile defense. As TWZ reports, whether such a system actually worked remains unknown. But today, alongside Russia’s hypersonic missiles capable of overwhelming U.S. defenses, such a technology could prove quite deadly indeed.

Darren lives in Portland, has a cat, and writes/edits about sci-fi and how our world works. You can find his previous stuff at Gizmodo and Paste if you look hard enough.

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