The spaceship was going to be enormous, sixteen stories tall and piloted by one hundred and fifty men. Project Orion seemed like a space vehicle from a science fiction novel, except it was real. It was the brainchild of a former Los Alamos weapons designer named Theodore Taylor, a man who saw space as the last “new frontier.”
For years, beginning in the early 1950s, Taylor designed nuclear bombs for the Pentagon until he began to doubt the motives of the Defense Department. He left government service, at least officially, and joined General Atomics in San Diego, the nuclear division of defense contractor General Electric. There, he began designing nuclear-powered spaceships. But to build a spaceship that could get to Mars required federal funding, and in 1958 General Atomics presented the idea to President Eisenhower’s new science and technology research group, the Advanced Research Projects Agency, or ARPA. The agency had been created as a result of the Sputnik crisis, its purpose being to never let the Russians one-up American scientists again. Today, the agency is known as DARPA. The D stands for defense.
At the time, developing cutting-edge space-flight technology meant hiring scientists like Wernher Von Braun to design chemical-based rockets that could conceivably get man to the moon in a capsule the size of a car. Along came Ted Taylor with a proposal to build a Mars-bound spaceship the size of an office building, thanks to nuclear energy. For ARPA chief Roy Johnson, Ted Taylor’s conception was love at first sight. “Everyone seems to be making plans to pile fuel on fuel on fuel to put a pea into orbit, but you seem to mean business,” the ARPA chief told Taylor in 1958.
General Atomics was given a one-million-dollar advance, a classified project with a code name of Orion, and a maximum-security test facility in Area 25 of the Nevada Test Site at Jackass Flats. The reason Taylor’s spaceship needed an ultrasecret hiding place and could not be launched from Cape Canaveral, as other rockets and spaceships in the works could be, was that the Orion spacecraft would be powered by two thousand “small-sized” nuclear bombs. Taylor’s original idea was to dispense these bombs from the rear of the spaceship, the same as a Coke machine dispenses sodas. The bombs would fall out behind the spaceship, literally exploding and pushing the spaceship along. The Coca-Cola Company was even hired to do a classified early design.
At Area 25, far away from public view, Taylor’s giant spaceship would launch from eight 250-foot-tall towers. Blastoff would mean Orion would rise out of a column of nuclear energy released by exploding atomic bombs. “It would have been the most sensational thing anyone ever saw,” Taylor told his biographer John McPhee. But when the Air Force took over the project, they had an entirely different vision in mind. ARPA and the Air Force reconfigured Orion into a space-based battleship. From high above Earth, a USS Orion could be used to launch attacks against enemy targets using nuclear missiles. Thanks to Orion’s nuclear-propulsion technology, the spaceship could make extremely fast defensive maneuvers, avoiding any Russian nuclear missiles that might come its way. It would be able to withstand the blast from a one-megaton bomb from only five hundred feet away.
For a period of time in the early 1960s the Air Force believed Orion was going to be invincible. “Whoever builds Orion will control the Earth!” declared General Thomas S. Power of the Strategic Air Command. But no one built Orion. After atmospheric nuclear tests were banned in 1963, the project was indefinitely suspended. Still wanting to get men to Mars, NASA and the Air Force turned their attention to nuclear-powered rockets. From now on, there would be no nuclear explosions in the atmosphere at Jackass Flats—at least not officially. Instead, the nuclear energy required for the Mars spaceship would be contained in a flying reactor, with fuel rods producing nuclear energy behind barriers that were lightweight enough for space travel but not so thin as to cook the astronauts inside. The project was now called NERVA, which stood for Nuclear Engine Rocket Vehicle Application. The facility had a public name, even though no one from the public could go there. It was called the Nuclear Rocket Test Facility at Jackass Flats. A joint NASA/ Atomic Energy Commission office was created to manage the program, called the Space Nuclear Propulsion Office, or SNPO.
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All NERVA employees entered work through a small portal in the side of the mountain, “shaped like the entrance to an old mining shaft, but spiffed up a bit,” Barnes recalls, remembering “large steel doors and huge air pipes curving down from the mesas and entering the tunnel.” Inside, the concrete tunnel was long and straight and ran into the earth “as far as the eye could see.” Atomic Energy Commission records indicate the underground tunnel was 1,150 feet long. Barnes remembered it being brightly lit and sparkling clean. “There were exposed air duct pipes running the length of the tunnel as well as several layers of metal cable trays, which were used to transport heavy items into and out of the tunnel,” he says. “The ceiling was about eight feet tall, and men walked through it no more than two abreast.”
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For each engine test, a remote-controlled locomotive would bring the nuclear reactor over to the test stand from where it was housed three miles away in its own cement-block-and-lead-lined bunker, called E-MAD. “We used to joke that the locomotive at Jackass Flats was the slowest in the world,” Barnes explains. “The only thing keeping the reactor from melting down as it traveled down the railroad back and forth between E-MAD and the test stand was the liquid hydrogen [LH2] bath it sat in.” The train never moved at speeds more than five miles per hour. “One spark and the whole thing could blow,” Barnes explains. At ? 320 degrees Fahrenheit, liquid hydrogen is one of the most combustible and dangerous explosives in the world.
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“The railroad car carried the nuclear reactor up to the test stand and lifted it into place using remotely controlled hydraulic hands,” Barnes explains. “Meanwhile, we were all underground looking at the reactor through special leaded-glass windows, taking measurements and recording data as the engine ran.” The reason the facility was buried inside the mountain was not only to hide it from the Soviet satellites spying on the U.S. nuclear rocket program from overhead, but to shield Barnes and his fellow workers from radiation poisoning from the NERVA reactor. “Six feet of earth shields a man from radiation poisoning pretty good,” says Barnes.
When running at full power, the nuclear engine operated at a temperature of 2,300 Kelvin, or 3,680.6 degrees Fahrenheit, which meant it also had to be kept cooled down by the liquid hydrogen on a permanent basis. “While the engine was running the canyon was like an inferno as the hot hydrogen simultaneously ignited upon contact with the air,” says Barnes. These nuclear rocket engine tests remained secret until the early 1990s, when a reporter named Lee Davidson, the Washington bureau chief for Utah’s Deseret News, provided the public with the first descriptive details. “The Pentagon released information after I filed a Freedom of Information Act,” Davidson says. In turn, Davidson provided the public with previously unknown facts: “bolted down, the engine roared… sending skyward a plume of invisible hydrogen exhaust that had just been thrust through a superheated uranium fission reactor,” Davidson revealed. Researching the story, he also learned that back in the 1960s, after locals in Caliente, Nevada, complained that iodine 131—a major radioactive hazard found in nuclear fission products—had been discovered in their town’s water supply, Atomic Energy officials denied any nuclear testing had been going on at the time. Instead, officials blamed the Chinese, stating, “Fresh fission products probably came from an open-air nuclear bomb test in China.” In fact, a NERVA engine test had gone on at Area 25 just three days before the town conducted its water supply test.
Had the public known about the NERVA tests when they were going on, the tests would have been perceived as a nuclear catastrophe in the making. Which is exactly what did happen. “Los Alamos wanted a run-away reactor,” wrote Dewar, who in addition to being an author is a longtime Atomic Energy Commission employee, “a power surge until [the reactor] exploded.” Dewar explained why. “If Los Alamos had data on the most devastating accident possible, it could calculate other accident scenarios with confidence and take preventative measures accordingly.” And so, on January 12, 1965, the nuclear rocket engine code-named Kiwi was allowed to overheat. High-speed cameras recorded the event. The temperature rose to “over 4000 ° C until it burst, sending fuel hurtling skyward and glowing every color of the rainbow,” Dewar wrote. Deadly radioactive fuel chunks as large as 148 pounds shot up into the sky. One ninety-eight-pound piece of radioactive fuel landed more than a quarter of a mile away.
Once the explosion subsided, a radioactive cloud rose up from the desert floor and “stabilized at 2,600 feet” where it was met by an EG& G aircraft “equipped with samplers mounted on its wings.” The cloud hung in the sky and began to drift east then west. “It blew over Los Angeles and out to sea,” Dewar explained. The full data on the EG& G radiation measurements remains classified.
The test, made public as a “safety test,” caused an international incident. The Soviet Union said it violated the Limited Test Ban Treaty of 1963, which of course it did. But the Atomic Energy Commission had what it wanted, “accurate data from which to base calculations,” Dewar explained, adding that “the test ended many concerns about a catastrophic incident.” In particular, the Atomic Energy Commission and NASA both now knew that “in the event of such a launch pad accident [the explosion] proved death would come quickly to anyone standing 100 feet from ground zero, serious sickness and possible death at 400 feet, and an unhealthy dose at 1000 feet.”
Because it is difficult to believe that the agencies involved did not already know this, the question remains: What data was Atomic Energy Commission really after? The man in charge of the project during this time, Space Nuclear Propulsion Office director Harold B. Finger, was reached for comment in 2010. “I don’t recall that exact test,” Finger says. “It was a long time ago.”
Five months later, in June of 1965, disaster struck, this time officially unplanned. That is when another incarnation of the nuclear rocket engine, code-named Phoebus, had been running at full power for ten minutes when “suddenly it ran out of LH2 [liquid hydrogen and] overheated in the blink of an eye,” wrote Dewar. As with the planned “explosion” five months earlier, the nuclear rocket reactor first ejected large chunks of its radioactive fuel out into the open air. Then “the remainder fused together, as if hit by a giant welder,” Dewar explained. Laymen would call this a meltdown. The cause of the accident was a faulty gauge on one of the liquid hydrogen tanks. One gauge read a quarter full when in reality there was nothing left inside the tank.
So radiated was the land at Jackass Flats after the Phoebus accident, even HAZMAT cleanup crews in full protective gear could not enter the area for six weeks. No information is available on how the underground employees got out. Originally, Los Alamos tried to send robots into Jackass Flats to conduct the decontamination, but according to Dewar the robots were “slow and inefficient.” Eventually humans were sent in, driving truck-mounted vacuum cleaners to suck up deadly contaminants. Declassified Atomic Energy Commission photographs show workers in protective gear and gas masks picking up radioactive chunks with long metal tongs.
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“We did develop the rocket,” Barnes says. “We do have the technology to send man to Mars this way. But environmentally, we could never use a nuclear-powered rocket on Earth in case it blew up on takeoff. So the NERVA was put to bed.”
A little-known fact, Annie Jacobsen explains (in Area 51), is that to prepare for what it would actually be like to walk around on the geology of the moon, the astronauts visited the Nevada Test Site: 
