It was nearly the end of World War II. But for the airmen of the 415th Night Fighter Squadron, it felt more like the beginning of War of the Worlds.

Lt. Fred Ringwald was the first to see it. He was riding as observer in a night fighter piloted by Lt. Ed Schlueter, with Lt. Donald J. Meiers on radar. It was a late November evening in 1944, partly cloudy with a quarter moon. They were roaming the Rhine Valley just north of Strasbourg on the French-German border when Ringwald said, “I wonder what those lights are, over there in the hills,” according to an American Legion Magazine story on the sightings from 1945.

There were eight to 10 of them in a row, glowing fiery orange. Then Schlueter saw them off his right wing. They checked with Allied ground radar, but they registered nothing. Thinking that the lights might be some kind of German air weapon, Schlueter turn the plane to fight…only to have the lights vanish.

At first the men said nothing, fearing they’d be ostracized. But then the sightings spread through the unit.

More crews, more sightings

On December 17, 1944, near Breisach, Germany, a pilot was flying at approximately 800 feet when he saw “5 or 6 flashing red and green lights in ’T’ shape.” The lights seemed to follow him, closing in “to about 8 o’clock and 1,000 ft.” before disappearing as inexplicably as they came.

Then on December 22nd, two more flight crews sighted lights. One crew, near Hagenau, reported two lights in a large orange glow, seeming to rise from the earth to 10,000 feet, tailing the fighter “for approximately two minutes.” After that, the lights, “peel off and turn away, fly along level for a few minutes and then go out. They appear to be under perfect control at all times,” according to Keith Chester’s Strange Company: Military Encounters with UFOs in World War II.

And then there was Lt. Samuel A. Krasney’s experience: a wingless cigar-shape object, glowing red, just a few yards off the plane’s wingtip. Lt. Krasney, justifiably spooked, instructed the pilot to attempt evasive maneuvers, but the glowing object stayed right next to the jet for several minutes before it “flew off and disappeared.”

Eventually, the airmen named the lights: foo fighters, inspired by the comic strip “Smokey Stover,” in which Smokey (a firefighter) would often declare, “Where there’s foo, there’s fire.”

The ‘Combat Fatigue’ Explanation

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An illustration depicting the December 22, 1944 encounter with 'foo fighters' during a daylight bombing raid on Germany during World War II.

An Associated Press reporter broke news of the foo-fighter sightings on January 1st, 1945, and theories about their origins quickly abounded: The sightings were flares, or weather balloons or St. Elmo’s Fire—a phenomenon where a light appears on the tips of objects in stormy weather. But the members of the 415th rejected all those theories. Flares and weather balloons can’t track planes like these objects could, and they’d seen St. Elmo’s fire and could distinguish the two.

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Then there were those who claimed that the airmen were suffering from “combat fatigue,” a polite way of saying that war stress was driving them insane. But there was scant evidence to suggest collective psychosis: The 415th had an otherwise excellent record, and when a reporter for American Legion Magazine went to report on the squadron he described them as “very normal airmen, whose primary interest was combat, and after that came pin-up girls, poker, doughnuts and the derivatives of the grape.”

Lt. Krasney’s son, Keith Krasney, says his late father didn’t fit the stereotypical profile of a UFO theorizer. In fact, he never even suggested that the glowing wingless cigar-like object that flew next to his plane was extraterrestrial in origin.

“He was very level-headed, very analytical,” says Krasney of his father, adding that he kept a notebook where he wrote about (and drew) his foo-fighter sighting. But although he never seemed prone to conspiracy theories, Krasney says his father was open to one: “He entertained the idea that it could be late-breaking German technology. He did express the view that there were a lot of things during the war that were kept quiet.”

Was it the Work of Nazi Astrophysicists?

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German-born rocket scientist Wernher von Braun, who was brought to the United States to work for the U.S. Army circa 1946

Holding Nazi Germany responsible for the flying glowing orbs isn’t too far-fetched. For one thing, the sightings took place over Nazi-occupied Europe, at a time when Germany’s Luftwaffe was making tremendous strides. Then there’s the fact that the sightings stopped once the German army was defeated.

But the most compelling link to the foo fighters might be Wernher von Braun, a 32-year-old wunderkind rocket engineer. Von Braun helped the Nazis develop the V-2 rocket: a long-range guided ballistic missile that Hitler was using in 1944 against Belgium and other parts of Allied Europe. It’s not to hard imagine pilots—unfamiliar with long-range ballistics—comparing these rockets to a cigar-like wingless planes. The V-2 could even explain the glow, since its tail emitted a long burning plume.

Nicholas Veronico, an author who has written several books on military aviation history, says that explanation comes up short.

“The V-2 rocket doesn’t have the maneuverability,” he says. “It couldn’t turn on a dime and change its acceleration pattern. Once it started burning, it burned and produced thrust at one rating.”

Nothing in Nazi Germany’s military-aviation arsenal can explain the foo-fighter description, Veronico says. One airman’s observation from the time—that the foo fighters follow the fighters so closely as to seem almost magnetized to them—is particularly confounding, given that “there just wasn’t the propulsion or metallurgical technology that could enable something like that.”

And yet von Braun’s career after World War II is worth considering. Following the collapse of the Third Reich, the engineer was recruited to be part of Operation Paperclip, a clandestine U.S. military program that spared 1,600 Nazi scientists prosecution for war crimes, moving them instead into the American military, where their past was whitewashed to the public.

By 1952, von Braun had reinvented himself as a space-flight advocate, writing a piece that year in Collier’s magazine declaring that “within the next 10 or 15 years, the earth will have a new companion in the skies, a man-made satellite that could be either the greatest force for peace ever devised, or one of the most terrible weapons of war—depending on who makes and controls it.” His prediction proved overly conservative: The Soviets launched Sputnik 1 only five years later. Von Braun helped the U.S. Army launch Explorer 1 shortly thereafter. By 1960 he was with NASA, where he became the chief architect on Saturn V—the rocket that sent Neil Armstrong and the Apollo 11 crew to the moon.

As von Braun recast himself as an American patriot, his career in the Nazi party shadowed him, an ambiguous secret that reporters would playfully poke at. At one press conference before one Apollo launch, a reporter asked von Braun to assure the press that the rocket wouldn’t hit London. But they could never prove his involvement, and it was only in 1985—several years after von Braun’s death—that CNN broke news of the full extent of the aerospace engineer’s Nazi past, more than 40 years after the fact.

Veronico hopes the foo-fighter narrative will follow a similar trajectory.

“The fantasy is that 100 years after the war, the U.S. or Soviets will release information about what they captured, and it’ll blow all our minds. But I think they would’ve capitalized on it by this point,” the historian says. “Or weaponized it.”