How to Survive an Atomic Bomb

In July of 1945, the men came down from the mesa to set off a bomb. They drove for hours from the secret wartime city of Los Alamos, New Mexico, to a desert test site called Trinity that they had been readying for months. They came in cars, in trucks, in busses, in Packard limousines—an inconspicuous convoy winding south into the wastelands of the Jornada del Muerto, a dry and deadly shortcut on the ancient Camino Real de Tierra Adentro, or “royal road of the interior land,” that had stretched north from Mexico City for centuries, carrying Indians, Mexicans, and conquistadors along one of the longest and oldest trails in North America that since 1680—when some six hundred colonists and converted Pueblos died in the crossing—had lived up to its name: “Journey of the Dead.”

The scientists were supposed to use Americanized code names, but they were properly known as Doctors Fermi, Segrè, Bohr (father and son), Weisskopf, Ulam, Teller, Rabi, Bethe, and von Neumann, among many others—an international mix of past and future Nobel Laureates; refugees and recent immigrants from Italy, Austria, Poland, Hungary, Denmark, Germany, Russia, and such; with a pair of Americans to lead them: J. Robert Oppenheimer and Major General Leslie R. Groves. With his crumpled brown hat, Oppenheimer would become the iconic atomic cowboy, a New Yorker turned California physicist who had chosen Los Alamos as a secret weapons lab because it was near the ranchland he had come to love. The army had converted a former boys’ school into barracks for the scientists; it quickly grew into a town. Accommodations were spartan, but the intellectual atmosphere was heady, electric—in some ways, they were still a bunch of boys at play. The scientists mocked the heavyset, bullheaded General Groves, who obsessed over security and—before taking control of the country’s brand-new nuclear program—had supervised the construction of the Pentagon.

For years they had worked tirelessly in fear of Hitler getting the bomb; nuclear fission had been discovered in Nazi Germany, after all. (That German atomic efforts were flailing was only discovered after the war.) The best minds of Britain and Canada had chipped in. Shipments of uranium and plutonium arrived from secret plants in Washington state and Tennessee. American Counter-Intelligence Corps dogged the scientists and tried to impose discretion: nuclear fission was to be called “urchin fashion,” while the bomb was known as “the Gadget.”

H. G. Wells’s 1914 sci-fi novel The World Set Free features the first use of the phrase “atomic bomb.” Envisioning a weapon powered by a radium-like element, Wells writes, “These atomic bombs, which science burst upon the world that night, were strange even to the men who used them.” In 1932, the book found its way into the hands of Hungarian physicist Leó Szilárd, who shortly thereafter conceived of a nuclear chain reaction. Szilárd would become one of the Manhattan Project’s atomic architects, though he always claimed Wells to be the true father of nuclear weapons. In the book’s dystopian future—1959—the world’s cities are leveled by atomic war. One character believes that the bombs might “shatter every relationship and institution of mankind.”

I fly to New Mexico on April Fools’ Day, 2015. I am coming to tour the Trinity site, which the army only opens to the public one or two days a year. This July will mark the seventieth anniversary of the first detonation of an atomic bomb. The blast area—which remains radioactive—occupies an abandoned section of a massive and still very busy missile range.

Descending through choppy air into the Albuquerque International “Sunport,” I look across the expanse of the adjacent Kirtland Air Force Base. I find the startling green patchwork of the base golf course and—just to the southwest—the pentagonal swath of desert that marks the Underground Munitions Maintenance and Storage Complex, the nation’s largest nuclear-weapons depot, whose blast doors alone cost $7 million. Thanks to the Kirtland base, New Mexico houses more nukes than any other state. (After failing a security inspection, the unit caring for those weapons was decertified for part of 2010.) The doors to the underground bunker aren’t visible from this height, but I can picture the twin ramps—one in, one out—that disappear into the earth, where some two thousand warheads wait underground.

In fission, the nucleus of an atom splits into two smaller parts, releasing subatomic particles and a burst of energy. In a hypothetical chain reaction, one neutron (supplied from the outside) splits an atom, which might emit two neutrons, which then go on to split two more atoms, which then release a total of four neutrons aimed at four more atoms, which release eight neutrons, and so on. If enough fissile material is present—called a critical mass—the reaction can become self-sustaining. The chain grows independently, exponentially, liberating greater and greater sums of energy. If there is enough mass—a supercritical amount—boom!

Criticality is a matter of density and volatility. Imagine the difference between shoving someone in an open field versus on a crowded New York subway. Some of the most dangerous experiments were ones in which the scientists tiptoed right up to that critical threshold—carefully bringing more and more fissile materials together to see when the burst occurred. They called the process “tickling the dragon’s tail.”

Of course there were accidents. Scientists suffered explosions and burns and berylliosis, an incurable lung disease caused by the inhalation of beryllium dust. A family cat lost its hair and died. If plutonium were to infect an open wound, protocol called for “immediate high amputation.” One physicist leaned over a naked pile of uranium-235—nicknamed “Lady Godiva”—and two seconds were all it took for his body to bounce back some of the neutrons, causing the stack to begin to go critical. Noting the wild behavior of his instruments, the scientist scattered the uranium, stopping the reaction. Another two seconds would have been fatal.

The key to an explosive chain reaction is speed—the fissile material needs to go quickly from a subcritical to a supercritical mass without lingering at the threshold, which might blow the bomb prematurely (i.e., produce a “fizzle”). In 1945, atomic bombs came in two kinds. The first was a gun-type assembly, in which a cordite explosion would fire rings of enriched uranium onto a smaller uranium plug, thereby achieving a critical mass. Because the device was so simple—and highly enriched uranium so scarce—this bomb (later known as “Little Boy”) could be dropped without ever being tested.

Meanwhile, the genius of the Gadget was implosion. In the second—more powerful and complex—design, a series of explosions would compress a core of plutonium into a critical state. Thirty-two precision-shaped charges (called lenses) were arranged in panels around a giant sphere (twelve pentagons and twenty hexagons, just like a soccer ball). All thirty-two lenses needed to fire simultaneously, producing shock waves that, as they traveled inward, would overlap to form a perfectly symmetrical spherical force, which would uniformly compress the plutonium into a dense, supercritical core. This bigger bomb, which would be tested at Trinity, would be named “Fat Man,” though—because of the implosion method—it initially was called “the Introvert.”

Some sixteen thousand nuclear weapons are sitting on the earth. Nine countries have the bomb: the United States, Russia, China, the United Kingdom, France, India, Pakistan, North Korea, and Israel. Russia and the United States account for more than 90 percent of the world’s nuclear arsenal. The U.S. keeps its nuclear weapons in eleven states (New Mexico, Missouri, Washington, Georgia, California, Montana, North Dakota, Texas, Colorado, Wyoming, and Nebraska) and five European countries (Belgium, Germany, Italy, the Netherlands, and Turkey). The U.S. stockpile is estimated to be around 4,760 warheads, plus another 2,300 warheads waiting to be dismantled.

To ensure its nuclear capabilities would be impossible to destroy in a preemptive first strike, the United States maintains a holy “nuclear triad”—a strategic mix of intercontinental ballistic missiles (ICBMs), submarine-launched ballistic missiles, and nuclear heavy bombers that remain at the ready. This is deterrence. Counting nukes can be something of a shell game, but according to numbers released by the government at the beginning of the year, the triad includes 447 Minuteman III ICBMs standing in silos across the heartland, 260 Trident II ballistic missiles (which can carry multiple warheads apiece) riding on 14 nuclear-powered Ohio-class submarines (10 of which are usually at sea at a time), and 87 B-52H Stratofortress and Stealth heavy bombers based in North Dakota, Missouri, and Louisiana—for a total of 794 deployed “delivery vehicles” carrying 1,642 warheads. The Russian Federation deploys only 528 delivery vehicles, but—in what feels like a symbolic bit of brinkmanship—counts a single warhead more.

The New Strategic Arms Reduction Treaty, which went into effect in 2011 between the U.S. and Russia, only limits the number of deployed strategic nuclear weapons. Both sides also have “tactical”—or battlefield—nukes, plus large strategic stockpiles, as well as the material to build more bombs. The U.S. currently stores enough plutonium to make ten thousand nuclear weapons, plus the highly enriched uranium for some sixteen thousand more.

Tumbleweed blows across the parking lot of the National Museum of Nuclear Science and History (just look for the towering red, white, and blue Redstone missile—marked U.S.A.—standing by the roadside). The entrance is guarded by twin surface-to-air missiles; a giant model of an atom hangs from the façade. Inside, a bunch of kids rush toward the bathroom to wash paint off their fingers; a brochure announces the museum offers summer camp. Inside, the atomic story is told in objects: bulky machines from Tennessee used to process uranium. The custom army-green 1942 Packard limousine that ferried scientists and officers down from Los Alamos, plus the American flag that greeted them at the Trinity base camp. A seismograph used in the Trinity test. Green chunks of sand—called “Trinitite”—fused by the blast. Huge weapon casings for Fat Man and Little Boy next to models of the B-29s that dropped them. A mock-up of the Gadget itself, wrapped in wires. A photo from Hiroshima of a dead three-year-old’s tricycle. A charred license plate from Nagasaki. A fallout shelter stocked with cans of General Mills “multi-purpose food” next to a Lance tactical ballistic missile bearing a W70 warhead. A Genie air-to-air rocket. A B61 gravity bomb, complete with parachute. A thermal battery, a nose fuse, a ready-safe switch. Dented bomb casings from two thermonuclear broken arrows that fell over Spain in 1966. Nearby, the Davy Crockett three-man nuclear bazooka. The Honest John rocket. A backpack nuke.

A visitor describes the concept of MAD—Mutually Assured Destruction—to his grandson. “And then we fire our missiles, and then they fire all their missiles. . . .” The kid’s father walks up. The old man says, “I’m trying to explain it all to the boy.” A nearby poster talks about “a stable but tense peace.”

The U.S. nuclear stockpile peaked in 1967 at 31,255 warheads. We have far fewer now, but that doesn’t mean our war power is impaired—one only needs so many bombs to lay one’s enemy to waste, particularly when each modern thermonuclear warhead might produce ten to fifty times the yield of the Gadget. Even though the Cold War is theoretically over and the geopolitical reality has shifted away from two superpowers straddling the globe, East versus West, we are in no rush to get rid of our nukes. In fact, our arsenal seems to be leveling out.

And here’s a startling fact: after adjusting for inflation, we spend more on nuclear weapons today than we did during the Cold War.

The Gadget had to be tested. A fizzle would give away the element of surprise, not to mention scatter design secrets and precious plutonium over enemy territory. General Groves needed a flat, isolated area with favorable weather that wasn’t far from Los Alamos. Over locations in California, Texas, and Colorado, he chose a site to the south in the high New Mexican desert between the San Andres and San Mateos mountains, just west of the Oscura peaks. The Jornada del Muerto land was mainly owned by the state and leased to ranchers; after Pearl Harbor, much of it had become part of the Alamogordo Bombing Range. Scouting the area in September 1944, the search team was nearly bombed by friendly fire from B-17s. Construction of the camp began in November.

Oppenheimer named his test “Trinity.” Even he wasn’t sure exactly why, but years later, in a letter to Groves, he cited poems by John Donne that contained the lines “Batter my heart, three person’d God” and “So death doth touch the Resurrection.” He had been introduced to Donne by Jean Tatlock, an old lover and Communist sympathizer who killed herself a year before the test.

The war in Europe was winding down, but the bomb project had its own momentum. Hitler was dead. So was Mussolini. Berlin had fallen. Auschwitz, Buchenwald, Bergen-Belsen, and Dachau had been liberated. Germany surrendered on May 7, 1945, the day the Trinity scientists conducted a preliminary test detonation of one hundred tons of TNT to which were added some radioactive material that would be scattered by the wind. The dirty bomb was meant to test blast effects and fallout, but the spectacular explosion—the largest to date, which was seen sixty miles away—was ultimately pointless in terms of predicting the performance of the Gadget, which would approach the TNT equivalent of twenty thousand tons. The question of radioactive fallout would rest with the physicians, not the physicists, who were mainly concerned with getting the bomb to work. General Groves was angry when he received the doctors’ report—he barked at the medical director, “What are you, some kind of Hearst propagandist?” Ultimately, fallout would depend on two unknowns: the strength of the blast and the force and direction of the day’s winds. The race for the bomb—that had now become one-sided—never slowed down.

The physicists weren’t without worry; they theorized calamities both mundane and spectacular, from earthquakes shaking far-flung cities to the birth of a new star. One early fear involved setting fire to the earth’s atmosphere. In 1942, when scientists first raised this possibility, Oppenheimer rushed to meet with his superior at the time, Arthur Holly Compton, who was at a summer cottage in Michigan. Compton drew a line. If the chances of apocalypse were more than three in a million, he would scuttle the bomb project. The scientists came back with odds just below that, so Compton decided it was worth the risk.

Many senior scientists were skeptical the bomb would even work. One hundred and two people paid a dollar to enter the betting pool to predict the force of the blast. Oppenheimer chose a mere three hundred tons. The winner—who still underbid—came closest with a guess of eighteen hundred.

Uranium for the project came from Mallinckrodt Chemical Works of St. Louis, which would go on to produce nuclear material for decades. Radioactive waste from the company was stored around town, contaminating the banks of the Missouri and Mississippi rivers, local landfills, and a suburban creek that ran through the childhood backyard of a friend of mine, whose old neighborhood has been found to have significantly higher rates of cancer. (In 2015, the Army Corps of Engineers found radioactive soil in parks periodically flooded by the creek.) At one radioactive landfill on the other side of the airport, an underground fire has been burning since 2010—with no sign of stopping. If the fire reaches the nuclear waste, the smoke plume could rain fallout over the region.

My own university is complicit, thick with atomic ties. In 1942, the U.S. government commandeered the highly efficient one-hundred-ton cyclotron at Washington University in St. Louis—a high-tech “atom smasher” built two years earlier at a cost of $100,000—to produce microscopic amounts of the new element plutonium, thus accelerating the bomb’s delivery by many months. For the next two years, in an underground building not far from my office, scientists irradiated material that was shipped to the Manhattan Project’s Metallurgical Laboratory in Chicago. Thirty-one faculty members and students participated in the bomb project, many of whom would leave to do wartime work at Los Alamos. The cyclotron was overhauled in the 1960s, but the original building remains.

From 1946 to 1953, the ninth chancellor of Washington University was Arthur Holly Compton, the apocalyptic oddsmaker who encouraged Oppenheimer to press on during the bomb’s early days. Compton was a deeply religious physicist who had directed Chicago’s Metallurgical Laboratory, overseeing the birth of the first nuclear reactor and, later, the use of such reactors to produce plutonium (for use in the Nagasaki bomb). For three years in the 1920s, before moving to Chicago, he had chaired the Physics Department, where he made a discovery about the scattering effect in X-rays that won him the 1927 Nobel Prize. After the war, he returned to St. Louis to become chancellor, and his inauguration featured a record gathering of atomic scientists.

Compton was on the four-person scientific panel that recommended to the Secretary of War and President Truman that the U.S. drop the bomb on Japan, a difficult decision he never backed away from, citing his belief that the bomb had saved lives and might eventually lead to the obsolescence of war. On campus, his signature can be seen everywhere. Upon becoming chancellor, he recruited six chemists from Los Alamos to modernize the Chemistry Department, where their portraits still hang. A building named after him houses the physics library. He designed speed bumps of ingenious pitch—that would discourage speeding but not break any milk bottles—which I drive or walk over every morning.

In the university archives, I pore over his papers. Correspondence with atomic giants, some of which was deemed confidential, vital to the national defense, and stamped with the Espionage Act. Petitions—from scientists at Los Alamos, Oak Ridge, and Philadelphia, from the Federation of Atomic Scientists, from the students of Bennington College—calling for an international body to control the atomic bomb. (Eventually, the Atomic Energy Act of 1946 gave authority over U.S. nuclear matters to a civilian—not military—domestic agency.) An address delivered two months after Hiroshima in which Compton envisioned a global nuclear holocaust unfolding in the year 1970. A contract for $1,000 for the movie rights to his life. A stub for a $750 check for consulting services provided to St. Louis’s Monsanto Chemical Company, which operated the secret nuclear laboratory in Oak Ridge, Tennessee. A letter dated October 1, 1945, from Compton’s older brother, Karl, president of MIT and scientific advisor to General MacArthur, cheering for the atomic bombing of Japan. And, from Compton’s personal library, Hermann Hagedorn’s epic poem, The Bomb That Fell on America, which holds between its pages a panel clipped from a 1948 Captain Marvel comic in which the red-suited superhero battles a radioactive robot called Mr. Atom. The panel contains the story’s clincher, which is bracketed in pen: “He who lives by the atom, dies by the atom.”

At the Nuclear Science and History museum, slightly unnerving explosions are coming from the children’s area, called “Little Albert’s Lab.” (It turns out the blasts are from the water electrolysis demonstration.) A medical bay shows the beneficial uses of radiation. We didn’t always fear this stuff—in the 1920s, the recommended dose from a radium-lined “Revigator” ceramic water jug was six glasses a day.

An exhibit on New Mexico’s Waste Isolation Pilot Plant contains cross-sections of drums containing fake radioactive waste. The nation’s only long-term storage crypt for nuclear waste, WIPP stands twenty-six miles east of Carlsbad, in the southeast corner of the state. Four shafts sink nearly half a mile into an extensive mine hollowed out of a 250-million-year-old salt bed below the Chihuahuan Desert. WIPP buries nuclear-weapon waste, not material from commercial nuclear power plants. Imagine rooms the size of football fields stacked with drums of contaminated tools, clothing, soil, and such, as well as plutonium once meant for bombs.

The Environmental Protection Agency certified that WIPP would last at least ten thousand years, as the salt beds would eventually collapse, trapping the waste. The time frame seems rather arbitrary, given that the most common isotope of plutonium lasts more than twice that long. Since 1999, WIPP has entombed nearly twelve thousand shipments, totaling ninety-one thousand cubic meters of waste, at a cost north of $7.5 billion.

In early February of 2014, a salt truck caught fire in part of the mine, which was closed. On Valentine’s Day, in a separate storage location, a fifty-five-gallon drum of waste from Los Alamos spontaneously ruptured, reaching a temperature of sixteen hundred degrees and leaking radioactive material that blew into the ventilation system, spread through the empty tunnels, and eventually reached the surface, where alpha radiation was detected more than half a mile away. Twenty-two workers tested positive for contamination. The likely culprit: a chemical reaction between nitrate salts and the sWheat Scoop natural kitty litter in which the waste was packed. The litter should have been clay based—in order to remain inert—but Los Alamos technicians confused the phrases “inorganic” and “an organic” when updating their packaging manual, and so a wheat-based litter was used. The Department of Energy agreed to pay the state $73 million in fines. The site isn’t expected to be fully operational again until 2021, after an estimated half-billion-dollar cleanup. (Meanwhile, the long-term price tag of the accident is expected to exceed $2 billion—rivaling the amount spent cleaning up the partial meltdown at Pennsylvania’s Three Mile Island nuclear power plant in 1979.)

WIPP holds only “transuranic” waste, meaning material with an atomic number higher than uranium. Thus when it is completed and sealed, WIPP will become a monument to man-made poison, a time capsule of our own folly. A series of redundant warnings is meant to remain legible for ten thousand years: giant earthen berms, massive granite monuments, buried markers, engravings, and pictographs. A 1993 report from the Sandia National Laboratories titled “Expert Judgment on Markers to Deter Inadvertent Human Intrusion into the Waste Isolation Pilot Plant” claims that no lasting barrier is feasible; there is no way to keep the future out, even once the site is sealed. The report suggests building menacing earthworks—fields of spikes and irregular blocks—around an empty center to suggest that there is nothing consecrated here, no treasure to be taken. The report proposes the use of facial icons that are not merely pained, panicked, and nauseated, but also mournful, bitter, and woeful. There is a tension inherent in the endeavor, a mix of pride and shame: while the site should be understood to be worthless, the markers must also inspire awe—or else they might be overlooked, vandalized, or erased. Ultimately, the report envisions WIPP not as a mine, or a monument, but a message—a system of meaning pantomimed across time, a history never forgotten, a past that must intrude eternally into the present:

“Sending this message was important to us. We considered ourselves to be a powerful culture.”

“This place is not a place of honor.”

“What is here is dangerous and repulsive to us.”

“The danger is still present, in your time, as it was in ours.”

“The danger is to the body, and it can kill.”

The month I was in New Mexico, the governor wrote to the U.S. Secretary of Energy, asking that an area not far from WIPP be considered as a repository for spent fuel rods from nuclear power plants—the most dangerous radioactive waste in the country.

At the Trinity site, the men watched 16 mm movies—The Prisoner of Zenda and Beau Geste—under the stars. Soldiers and scientists played volleyball, poker, and polo (on horseback with brooms and a soccer ball). With submachine guns, they hunted antelope, which were served up as steak. With little else around them but aerial targets, one night the base camp was bombed in error by planes from the nearby Alamogordo Bombing Range, setting the stables afire. Three days later, the carpentry shop was hit. The test director suggested installing anti-aircraft guns.

By July 1945, the month of the test, nearly three hundred people were housed at Trinity, a number that would rise to 425 two weeks later for the test weekend. A laboratory now occupied the alkali plain, which was crisscrossed with five hundred miles of instrument lines stretched between wooden T-poles standing about the height of a man. More wires were buried in garden hoses in the sand. There were impulse meters, geophones, and peak pressure gauges. More than fifty cameras—motion-picture and still—were assembled to capture the explosion, everything from high-tech Fastex devices recording ten thousand frames per second behind bunkers of steel and glass to a simple pinhole camera, operating under the ancient principles of the camera obscura. Photographers were given incomplete information, told simply to be ready to film something historic that would begin with the light of ten burning suns. (The only successful color photo of the blast would be taken by a technician who—as an amateur photographer—had brought his own camera.) Three shelters with concrete slab roofs were buried ten thousand yards to the north, west, and south of Ground Zero, where a one-hundred-foot steel tower rose above the desert. At the top stood an oak platform shielded by corrugated iron. The tower was anchored by concrete footings buried twenty-five feet deep.

The test was originally targeted for July 4, but by mid-June Oppenheimer said the thirteenth was the earliest it could be. Eventually, a date came down from Groves—July 16, during the predawn hours—despite that it was not within the first or the second range of days given by the chief meteorologist, but instead would fall during a period of predicted storms, which could concentrate fallout.

At the museum, I step outside into Heritage Park, where the thirty-foot sail of a nuclear sub rises improbably out of the sand. A B-29 bomber looms beside the atomic cannon; a sign warns KEEP OFF. A military plane drones low overhead, coming in for a landing at Kirtland, and beyond the fence I see the glass-faced tower of the Sandia National Laboratories complex, one of the country’s three remaining nuclear labs, where the parking lot is full. Behind a B-52 stands an enormous Mark 17 bomb, just like the one that on May 22, 1957, accidentally slipped out of the bay of a bomber landing at Kirtland. The 41,400-pound thermonuke—the largest the U.S. ever deployed—fell just outside of Albuquerque on land owned by the University of New Mexico, blowing a twenty-five-foot crater and killing a cow. Had the bomb been armed, the explosion would have been five hundred times that of the Trinity blast.

On the other side of the park, a rusting three-stage Minuteman missile lies along the fence, its sign also down, having fallen against the tail. I turn, and the wing of a B-47 bomber almost clips my brow. I put my head into the blackened thruster of a colossal Titan II intercontinental ballistic missile lying in stages on the ground and imagine the heat, smoke, and smell of all that it burned.

Four days before the test, on Thursday, July 12, the massive body of the bomb—the high-explosive sphere that would encircle the core—was bagged in plastic, boxed in pine, covered by tarp, and tied to the back to a five-ton truck, which left the mesa at midnight, just as the calendar turned to Friday the 13th. The scientists laughed at superstition, but two Army Intelligence cars joined the convoy, which blared a siren as it rolled through sleeping Santa Fe, to discourage drunks from crashing into them.

Earlier that day, an army sedan had left Los Alamos carrying physicist Philip Morrison, who, in a month, would assemble the bomb dropped on Nagasaki, before becoming a popular scientist and staunch opponent of nuclear proliferation. Morrison sat in the backseat next to a shockproof box—designed to bounce if dropped—that contained the two hemispheres of the Gadget’s plutonium core. Upon arriving at the Trinity site, the army lieutenant was directed to deliver the top-secret package to a ranch house two miles from Ground Zero.

On the morning of Friday the 13th, in the master bedroom of the ranch house, where the windows were taped against the dust, Canadian physicist Louis Slotin began assembling the bomb’s plutonium core, which was about the size of an orange but weighed a startling thirteen pounds. Slotin Scotch-taped a small neutron initiator made out of polonium and beryllium—called an “urchin”—into a hollow pit in the middle of the plutonium hemispheres. Upon being crushed by the shock wave of the explosions, the urchin would release a burst of neutrons to start the chain reaction. The plutonium sphere itself would nestle inside an eighty-pound cylindrical plug made of uranium-238, part of the “tamper” that would reflect more neutrons back onto the critical mass and inhibit early expansion of the material, which might weaken the reaction.

Slotin would earn the nickname “chief armorer of the United States.” Ten months later, he would be killed after showing some colleagues—on a whim—how to tickle the dragon, lowering the top half of a tamper onto a plutonium core using nothing but a flathead screwdriver to hold the hemispheres apart. The screwdriver slipped, the sphere became whole, and there was heat and a bright-blue flash. Slotin flung off the tamper, but it was too late—he soon began vomiting. (Three of the other seven witnesses would later die from radiation-related diseases.) The core had already killed Slotin’s assistant nine months earlier, when he dropped a tungsten brick next to it. He had taken about a month to die. Slotin would last nine days, after his parents had flown in, his face turned red, his skin blistered, and his hair began falling out. Coughing but coherent, he suffered through his final hours struggling to answer questions on camera. The footage was made into a training film for nuclear technicians that was shown at least until the late 1970s.

At 3:18 p.m., the Trinity core arrived at the base of the tower, where it was to be inserted into the two-ton, five-foot ball of explosives. The body of the bomb was a carefully calibrated device: the implosion lenses had been X-rayed, and each tiny air pocket had been drilled and filled with explosives. The blast waves had to arrive in precise synchronicity. Some of the charges were made to fit snugly with tissue and Scotch tape. A declassified film shows the scientists working under a large canvas tent. Oppenheimer leans over his Gadget, hat on, sleeves rolled up. The men—some topless, others in T-shirts and tanks—stick their arms deep into the top of the bomb. There was a moment of panic when the cylindrical plug—containing the plutonium core—didn’t fit, but someone realized the metal had simply expanded in the heat. Once it cooled off, it slid in perfectly. One step at a time, the scientists followed the painstaking assembly instructions set down for the “hot run”: “Place hypodermic needle in right place. (Note: Check this carefully) . . .” and so on. When they were done, some men went swimming in a water tank. The next morning, a $20,000 winch raised the Gadget to the top of the tower, where the detonators were installed. As it went up, a pile of striped G.I. mattresses were placed beneath the bomb. A handwritten sign advised WEAR A HARD HAT.

That night in Albuquerque, I dream of bombs going off. In the morning, I wake to hear Russia is threatening to use nukes over the Ukraine. Later, over huevos rancheros, I read that a break has come in nuclear talks with Iran. Driving south out of town, I see the ballpark for Albuquerque’s minor-league team, the Isotopes. Winds whip across the desert, throwing a mattress off the roof of a car and onto the highway. I keep the dark mountains on my left as dust storms roll through the valley like fog. I pass a dead coyote on the road.

We are facing a future of fewer but better bombs. The average U.S. warhead is twenty-seven years old. The government expects to spend more than $350 billion in the next decade—and at least $1 trillion in the next thirty years—to update its nuclear arsenal. Plans include designing a new nuclear sub, a long-range bomber, and an air-launched cruise missile, as well as looking into the next generation of land-based ICBMs. Older designs will be retrofitted. One bomb—the B61, which dates to 1963—is scheduled to get a new tail assembly, making it less of a gravity bomb and more of a guided weapon, greatly increasing its accuracy (and lessening the need for a huge yield). The B61 upgrade will cost more than $10 billion, which—as the Bulletin of the Atomic Scientists has pointed out—means each new bomb will cost more than if it were made of gold. Waste is one thing, but analysts have noted an even more troubling drawback: with more precision—and fewer unintended casualties—comes a greater enticement to actually use a nuke.

I spend the night in Truth or Consequences (pop. 6,100). A spa town, “T or C” originally was incorporated as Hot Springs, but, in a 1950 publicity stunt, renamed itself after a popular quiz show. After a multimillion-dollar commercial “spaceport” opened nearby in 2011, the town has geared up for an influx of space tourists that may or may not ever arrive. (Flights, on carriers such as Virgin Galactic, have yet to take place.) I’m staying at the Rocket Inn—in the Apollo Room, as it happens, which celebrates our mission to the moon, which blazes nearly full tonight, ringed by a double halo. As I stand ogling it, one of the motel owners strolls by, saying, “Wow, look at that.” The air smells of wood smoke. I go back inside and prowl around my room. The hot springs that bubble up into the historic bathhouses downtown are heated by the same radioactive decay that fires the inner earth. Last night, in my atomic nightmares, I was stranded between terror and wonder—panicked, but giddy to be at Ground Zero. How I wanted to see the blast, to witness the fallout. Tonight is so quiet. You can hear every stray voice or dog, every screen door slam, every car hit the gas as it decides to keep on rolling through the valley. I know the name is just a worn-out gimmick—one that doesn’t ring many bells anymore—but tonight the choice feels dire, fatalistic. Truth or Consequences. Well, which is it going to be?

Everyone pays lip service to a world without nukes, but we are not the only ones refusing to put away our bombs. Russia is upgrading Sovietera systems, enhancing its bomber force, and building three new land-based missiles. Meanwhile, China is adding to its arsenal, while India and Pakistan are increasing their abilities to produce plutonium and uranium. Britain is building new missile subs, and France and Israel are improving their capabilities. Meanwhile, as global disarmament stalls, the nuclear have-nots express growing resentment.

We have nonnuclear weapons of amazing power and precision—the technology of conventional war has raced ahead, unchecked—but the point of a nuclear weapon is fear: the fear that someone, somewhere (either us or them) will get pushed too far, and everything—everything!—will come to an end. Mutually Assured Destruction is a position of pure reason and pure madness, and it’s not a line to be crossed, or a point to tip past, but a delusional dream state that we’ve inhabited for more than sixty years. The logic of deterrence is a closed circle, a serpent eating its own tail. There will always be another enemy—monolithic, inscrutable, duplicitous—that must be kept cowed. There is pleasure and comfort in that. But, for example, what use is a nuke against a man with a box cutter?

Obsolescence takes a mental toll. For instance, missileers know that owing to geography, in order to fire our ICBMs at China, Iran, or North Korea—today’s lineup of “villains”—the missiles would have to fly over Russia without provoking a response—a wildly unlikely scenario, to be sure. America’s nuclear morale—on bases, in labs and facilities—is dismal. Ambitious young scientists aren’t eager to babysit old bombs that can no longer legally be tested. Soldiers don’t want to sign up to sit in useless silos. Stories of drug use, security breaches, boredom, burnout, cheating, and catastrophic close calls have appeared recently with some regularity—including the one about the six thermonuclear missiles that were “lost” for thirty-six hours and mistakenly flown across the country, unguarded. Or the eighty-two-year-old nun who managed to breach the nation’s most secure uranium storage facility deep in the Tennessee woods, where she and her two companions splashed blood on the building.

Late last year, even the Vatican, long a believer in deterrence, backtracked on nukes, calling the very possession of them immoral.

Policy-wise, the U.S. occupies a weird middle ground—we want to manage a reduced but still-robust nuclear stockpile, while somehow imparting the idea to our nonnuclear allies and enemies that atomic weapons aren’t the way to go. The official government rhetoric walks a curious line, downplaying our commitment to nukes while at the same time confirming our willingness to use them, if pushed. Meanwhile, we’re all up to our old Cold War stunts again, Russia buzzing Europe and Alaska with its nuclear bombers, while we test-launch two ICBMs in a single week.

Atomic tourists aren’t the only ones making pilgrimages to New Mexico. The state also advertises a fifty-two-stop “space trail,” which includes a visit to Spaceport America, which was built in one of the poorest states in the country with some $200 million of New Mexican taxpayers’ money. The next morning, I get up early for a tour. I am the last of the fifteen space enthusiasts in the van. Our driver, Gary, talks nonstop over the PA during the forty-five-minute trip. We pass the beautiful Elephant Butte Dam, part of the Rio Grande Project, which delivers water to New Mexico and Texas. I am startled to see a sparkling blue expanse stretching miles into the desert, the reservoir where the frazzled Trinity test director and his assistant recovered on a fishing trip before returning to dig out their equipment. Everyone in this part of the state talks about water.

Gary asks for the hand of anyone who has signed up for a Virgin Galactic flight. No one moves; we are strictly terrestrial space tourists. He says, “I understand. It’s that big number with a lot of zeros between us and space.” Specifically, a flight costs $250,000, a price some seven hundred would-be astronauts have already paid. Buying a ticket is hardly a sure thing. Even before the October 2014 crash that delayed Virgin Galactic’s schedule for luxury space flights, the spaceport was sitting empty, mainly used for photo shoots by Land Rover and Kawasaki.

Why build the world’s first spaceport in the middle of nowhere, New Mexico? The reasons are surprisingly similar to the Trinity test. First, Gary tells us, it has to do with seclusion and privacy. “There are more cows than people. A lot of companies don’t want the world looking over their shoulder.” Then there’s the weather: an average of twenty-eight sunny days a month. The high elevation is also a boon—“we say you get the first mile for free!” And thanks to the adjacent White Sands Missile Range—the vast army installation that has swallowed up the old Alamogordo Bombing Range and the Trinity test site—the airspace above this area is restricted upward to infinity. Gary tells us the White House is the only other location with complete overhead clearance, before launching into a long argument for privatized space. Meanwhile, we pass a dirt road tentatively scheduled to be paved by the end of the year, which would connect to the interstate and thus bypass Truth or Consequences.

The spaceport’s Gateway to Space Building nestles between two earthen berms. From the back, the oxidized-steel hangar looks like twin turtle shells. It’s off-limits to tourists, but I imagine the rich and famous disappearing into the darkened entryway, where they will board a ship that will allow them to slip the bonds of earth—for only a few weightless minutes—after which they, like everyone else, will be brought right back down where they came from.

I drive north to Socorro. Colorful crosses hung with paper flowers line the side of the highway. More death in the desert—I’m reminded that today is Good Friday. The sun is bright; I keep seeing shapes in the brush and mirages on the road. At last I pull into the old town square of Socorro, where men sit on benches in the shade and a historic marker talks of what happened at Trinity seventy years ago. Tomorrow the site will be open to the public. As I check in to my hotel, I hear British accents behind me.

At the northern edge of White Sands, a notice says the road can be closed for missile firing and gives a number to call. Seventeen miles past the gate to the range—which won’t be open until 8:00 a.m. tomorrow—a tall, weathered wooden sign—ROCK SHOP—springs out of nowhere. I pull over and two big dogs start going nuts behind a fence. The yard is strewn with metal tables piled with colorful slabs, geodes, agates, jaspers, boulders, and, strangely, seashells. A woman in a tank top appears and asks what I want. I tell her I’d like to see the rocks. She unlocks the shop, which has been open since 1968 and consists of a number of rooms stuffed with rocks, minerals, gems, and jewelry. The owner, a suntanned older woman with very blue eyes, says she took over in the mid-1990s.

I buy a small piece of Trinitite that was picked up by a miner before the blast field was bulldozed in the 1950s. The glazed green rock is illegal to collect, but my piece is grandfathered in, she tells me. She says it emits .08 millirem per hour of alpha radiation. (A Geiger counter will measure somewhat less than that back in St. Louis.) I ask if the rock is dangerous. “Just don’t crush it up and snort it,” she says. And here she’s not joking. While alpha particles usually can’t penetrate the skin, they are bad news inside the body. She doesn’t mention the beta particles, which I know the piece is sending out, too, though they’re also relatively weak and stopped by a thin layer of metal.

What was borne in that green glass? A mottled chunk of plutonium, uranium, sand, steel, minerals, and dust, forged in fire and rained down from above, the shiny side cooling to reflect the sky. I’m not sure why I buy the sample. Partly out of guilt for making the woman open the shop just for me—the last visitor signed the guest book a month ago—but that’s not entirely it. I’m standing about 18.5 miles to the northeast of Zero. This tiny town—now essentially gone—was bathed in radiation that day. The readings were some of the highest measured. As I drive away, I will think of roving monitor Arthur Breslow, who—chasing the cloud—left his respirator at a searchlight station he had been forced to evacuate, and so drove on through the radioactive valley with his windows rolled up, breathing through a piece of bread. One family who lived off this road was advised to stay indoors—for days. This hot rock is a terrible memento mori. I put it far away on the floor of the passenger seat. The last thing the woman at the shop told me: “Tomorrow is going to be a wild day.”

The scientists’ to-do list for Sunday, July 15, the day before the test, included “look for rabbits’ feet and four-leaved clovers.” Late that night, a thunderstorm moved in. The youngest scientist, Don Hornig, who had designed the electric trigger, was dispatched to the open metal shack at the top of the tower, where he sat alone with the bomb, which was now wrapped in thirty-two thick detonation cables set to simultaneously explode. Everyone was worried about sabotage and lightning. A week before, static electricity had prematurely triggered the firing unit. Hornig was unarmed and unclear what to do in the case of an emergency. He passed the time reading humorous essays by the light of a dangling bulb. Later, he would advise Eisenhower, Kennedy, and LBJ, and become the president of Brown University. He was the last to leave the tower.

The scientists were exhausted and on edge. Four psychiatrists from the secret site in Tennessee were ready to be flown in. The day before, a nonnuclear test of a dummy bomb had failed. (The lenses were not right.) The explosive expert bet Oppenheimer a month’s salary that the lenses would work on the real thing. Everyone was watching the sky. Moisture might short out the triggers; storms could blow radiation over nearby towns. Surveying the Oscuras in the dusk, Oppenheimer cryptically confided to a metallurgist: “Funny how the mountains always inspire our work.”

Scientists took their stations. The southern shelter was the control room. The other two housed searchlights, cameras, and instruments. More scientists would observe from base camp, ten miles to the southwest of the tower. The VIP area—which would include nonessential staff, visiting scientists, military men, and a single journalist handpicked from the New York Times—was on a hill about twenty miles to the northwest.

At 1:00 a.m., General Groves was trying to catnap in a poorly secured tent when he was awakened by canvas flapping in the wind. At 2:00 a.m., just as the busses of VIPs were arriving from Los Alamos, more violent thunderstorms rolled into the area, lashing the control bunker and base camp with high winds, but for the most part sparing the tower. The shot was scheduled for 4:00 a.m., but at 2:00 a.m. it was decided to postpone the test until at least five o’clock, when the meteorologist thought the storms would clear. General Groves threatened to hang him if he was wrong.

At 2:45 a.m., the general called the governor of New Mexico and alerted him that it might become necessary to enforce martial law. The reporter from the Times had left several press releases back in New York, including one that described an accident at Oppenheimer’s mountain ranch that had claimed the lives of many prominent scientists, as well as the writer’s own. Base camp began serving breakfast at 3:45 a.m.: powdered eggs, French toast, and coffee. Meanwhile, two physicists observed a heap of frogs breeding noisily in a rain-flooded hole. The weatherman made his last forecast at 4:15 a.m. At eight minutes past five, the test director examined it. Both men had been awake for two days. The conditions were far from ideal, but by a stroke of luck, the winds were favorable.

Twenty-nine people were in the north shelter, thirty-seven in the west, and thirty-three in the south, the control bunker, where Oppenheimer was stationed with other crucial personnel. General Groves watched separately—at base camp—to lessen the chances of both men being killed (which would be a terrible setback for the project). In an attempt to frighten the guards, one Nobel Laureate began taking bets on whether the bomb would destroy the whole world, or merely New Mexico.

Trinity was plagued by echoes: the shortwave frequency happened to overlap with a freight yard’s in San Antonio—the scientists and the rail men could hear each other’s traffic. The ground-to-plane frequency matched the Voice of America’s, startling some physicists with bars from the “Star-Spangled Banner.” On the observation hill, theoretical physicist Edward Teller, who would become known as the “father of the hydrogen bomb,” passed out suntan lotion, which everyone applied in the dark. The Gadget was twenty miles away. Teller wore heavy gloves and welder’s goggles—to the dismay of some of the more unsuspecting MPs standing by. Down the road, a man named J. E. Miera, who grilled hamburgers for the scientists in his popular Owl Bar, was awakened by soldiers sitting outside with seismographs. They told him to come out front to witness “something the world has never seen.”

The Owl Bar and Café still stands in the little town of San Antonio. Tonight, a tattooed older vet in a black T-shirt is drinking tequila and a beer. He used to work at Los Alamos and tells the bartender, “I don’t exactly see why everyone gets so worked up about visiting where they set the bomb off.” The bartender tells him about local kids who grew up with problems, special needs, cancer. Despite his nonchalance, the man says he’s thinking about finding a spot and sleeping by the side of the road to avoid the line of cars in the morning. “There’s nothing posted against it,” he says.

Rowena Baca tells me a story she has told many others who have come through her bar, a beautiful old dive adorned with autographed photos and dollar bills pinned to the walls. She is the granddaughter of J. E. Miera, the grocer who was woken early and told to come outside, where I had just parked my car. “The men—I don’t know whether they were soldiers or scientists—would rent cabins from my grandpa,” she says. “They said they were prospectors. Daddy always said they were really nice guys.”

Just after 5:00 a.m., the test director unlocked the switches. Soldiers stood in slit trenches. Radiation monitors swung from blimps that would be vaporized upon relaying their data. At 5:03 a.m., as the timer began, the order was repeated for everyone, everywhere: lie facedown on the ground, feet to the blast—don’t look until the first flash is over. Two minutes later, the last men left the base of the tower, calmly driving five and a half miles to the southern shelter. At 5:10 a.m., over a loudspeaker, Samuel K. Allison of the University of Chicago began the first countdown in history. (He came up with the idea to count backward to the blast.) General Groves rode a jeep to base camp, where one man insisted on facing the explosion. Everyone else lay down in the trenches.

At T-minus five minutes, a green warning rocket flared. Another, three minutes later, refused to fire. With a minute to go, Oppenheimer is said to have remarked, “Lord, these affairs are hard on the heart.” He gripped a post and seemed to hold his breath. At T-minus forty-five seconds, one of the arming party threw the final switch. The bomb would now fire automatically. A chime accompanied Allison on the countdown. At ten seconds, a gong clanged in the control shelter. One physicist cried to another, “Now I’m scared!” Most everyone was praying. At nine seconds, interference with a local radio station cut in over the loudspeaker—and the scientists were treated to the cheery dissonance of Tchaikovsky’s “Serenade for Strings,” which was currently featured in the MGM musical Anchors Aweigh. At base camp, General Groves lay on the ground between two scientists thinking of what he would do if the zero came without a bang.

At the Owl, Rowena Baca sits at a twenty-five-foot solid mahogany bar her grandfather installed in his store more than seven decades ago. He paid some soldiers to walk the bar three-quarters of a mile down the road from an old rooming house that belonged to Gus Hilton—of that Hilton family, who hail from San Antonio. It took the soldiers two days. They were paid in hamburgers and beer. Years later, Conrad Hilton’s son returned, trying to buy back the bar. He promised to build her a replica. She refused. “To me, it’s priceless.”

The guy to my left was last here in 1962, when he got a job right out of high school working on the interstate. “We were only eighteen, nineteen, but Frank,” meaning Baca’s father, “would let us drink beer.” He says the place has stayed the same. Baca still gets to work at 7:00 a.m.—though she closes the bar earlier these days. She says, “Daddy paid me fifteen dollars a week when I was twelve—and I’ve been in the grocery business ever since.”

She has noticed a steady rise in tourists attending the Trinity open house. She says Japanese visitors have started to show up in recent years, too. She brings up the protesters who will come from across the state to be here tomorrow—they want recognition and compensation for being atomic test victims. Baca says, “We were the ones closest, but all the old timers are gone. There’s nobody left to get the money.”

Baca was a toddler that morning in 1945. She remembers, “Grandma thought it was the end of the world. Everything was red. She threw me and my cousin under the bed.” Then she adds, “We were crying under there. I don’t know why she thought the bed would save me.”

Finally, on July 16, 1945, at 5:29:45 Mountain War Time, the Gadget exploded in the predawn dark with the light of twenty suns.

Someone said it smelled like a waterfall. But first came a flash visible from three states that dimmed to reveal a boiling mushroom cloud that shot skyward in perfect silence, burning red then luminous purple as it ionized the atmosphere. In seven minutes, the column would stretch more than seven miles tall. The MP guarding the door of the control bunker went pale; nobody had thought to explain to him what would unfold. At the site of the roiling cloud, an officer worried, “The longhairs”—or scientists—“let it get away from them,” while General Groves deadpanned, “Well, there must be something in nucleonics after all.”

A physicist remembered, “It was like being at the bottom of an ocean of light. We were bathed in it from all directions. The light withdrew into the bomb as if the bomb sucked it up. Then it turned purple and blue and went up and up and up.” The War Department officially reported a radiance “golden, purple, violet, gray, and blue” that “lighted every peak, crevasse, and ridge of the nearby mountain range with a clarity and beauty that cannot be described.” From a car headed to Albuquerque, a partially blind music student even saw the flash. Physicist I. I. Rabi on the light: “It blasted; it pounced; it bored its way right through you.”

The heat struck hard in the cool morning. To observers in base camp—ten miles away—it felt like standing in front of a fireplace. A glowing yellow turbulence raced across the desert floor, whipping up sand—the shockwave beating the ground toward them. Unable to keep still, one scientist dropped six pieces of paper before, during, and after the wave’s arrival—just another way of calculating the force of the blast. It took forty seconds for the shock to hit base camp, and with it finally came the sound—a deep booming that ricocheted through the valley and canyons until the echoes collapsed into a continuous roar. Thirty-four years later, one witness would write, “I can still hear it.”

Outside the control bunker, the shockwave flattened the explosives expert, who had neglected to duck. He got up and hugged Oppenheimer, before asking his boss to make good on their bet. A conga line broke out, and people took turns shouting over the PA. Elsewhere, a man who had burned his corneas was given morphine.

The New York Times journalist would write, “One felt as though he had been privileged to witness the Birth of the World—to be present at the moment of Creation when the Lord said: ‘Let There Be Light.’” Oppenheimer strutted around like a cowboy. The test director told him, “Now we are all sons of bitches.” One scientist passed whiskey.

Another asked, “What have we done?”

I wake before dawn to a blood moon setting over the western mountains. An auspicious alignment: the total eclipse of a full moon, the earth’s shadow casting it a fearful red—an ancient sign of apocalypse. Recently, a few fringe Christian ministers have prophesized that this blood moon—one of four in a row—foretells the end of the world. (Revelation 6:12: “And I beheld when he had opened the sixth seal, and, lo, there was a great earthquake; and the sun became black as sackcloth of hair, and the moon became as blood.”) From my hotel parking lot, I stare dumbly at the red orb as a biker straps gear onto his ride. The air is cold and clear; the sun won’t be up for a while.

In the lobby, a flyer advertises a religious revival called “the minor prophets’ guide to the end times.” It’s at a place called Quemado—or burned—Lake, and promises “good old Bible preaching.” Yesterday was Good Friday. Last night was Passover. A time of great Biblical death—Christ on the cross, all those firstborn Egyptian sons. Today is Holy Saturday, the day Jesus descended into hell. Tomorrow will be Easter. And so I go to Trinity.

The smoke covered the ground for an hour. When the fireball touched down, it blasted a half-mile crater. Everything within another half mile beyond that was dead—down to the ants. The smell lasted three weeks. Doors were torn off a farmhouse three miles away. Downwind, cattle would die. At twenty miles, a black cat’s fur would go white. Five miles beyond that, monitors found a stunned mule, tongue lolling out. The air blast broke windows in Silver City and Gallup, the latter some two hundred miles away. In a 1965 television documentary, Oppenheimer recalled, “We knew the world would not be the same. A few people laughed, a few people cried. Most people were silent. I remembered the line from the Hindu scripture, the Bhagavad Gita. Vishnu is trying to persuade the prince that he should do his duty and, to impress him, takes on his multi-armed form and says, ‘Now I am become Death, the destroyer of worlds.’ I suppose we all thought that, one way or another.”

Four hours after Trinity, the Indianapolis slipped out of the San Francisco Bay, headed to the western Pacific and carrying in its hold the Little Boy bomb that three weeks later would explode over Hiroshima.

At base camp, General Groves wanted to wait out the fallout by discussing the logistics of the next assignment—dropping a bomb on Japan—but found, to his disappointment, that the scientists weren’t in the right “frame of mind.” Oppenheimer’s younger brother, also a physicist, described a feeling of dread: “I think the most terrifying thing was this really brilliant purple cloud, black with radioactive dust, that hung there, and you had no feeling of whether it would go up or drift towards you.”

Within fifteen minutes, the mushroom cloud had divided into three, a most unholy trinity. The lowest portion moved north, while the middle went west. Some fifty thousand feet up, the largest and highest part drifted northeast—exactly as desired. Another fifteen minutes later, the top of the mushroom was said to resemble North America, while the remaining clouds formed a reddish-brown question mark. Five minutes later, the lowest, heaviest cloud swept over the north shelter, forcing it to evacuate. But for two hours, very little fallout came down, which raised hopes—before the top cloud irradiated a long stretch of land one hundred by thirty miles. (That day, gamma rays would be detected 260 miles away in Colorado.)

Twin B-29s followed the high white cloud for miles, before losing it in the thunderheads. Other aircraft tracked it for several hours beyond that. The head meteorologist, at the controls of his own plane, estimated that in thirty-six hours it would circumnavigate the globe. Before then, the first radioactive cloud slowly sailed east over Kansas, Iowa, Indiana, New York, and New England.

The protesters carry signs that read NEW MEXICO IS NOT RADIATION PROOF and SPEAKING UP FOR THOSE WHO HAVE BEEN SILENCED BY THE BOMB. After I pass them, I will spend about an hour waiting in a line of vehicles four miles long to get to the entrance of the missile range. A tiny Yorkie hangs its head out of the Jeep behind me, which makes me think of the army dogs that used to sniff out exploded missile fragments in the sand. I see cattle and smell burning rubber. A motorcycle cruises by in the left lane, cutting the line, and people honk. On the mountains ahead, I can see the telescopes of the Lincoln Near-Earth Asteroid Research project, which for decades have watched the skies for threatening space objects.

At thirty-two hundred square miles—the size of Rhode Island plus Delaware—White Sands Missile Range is the largest military installation in the U.S. Since 1945, the range has hosted a number of historic moments in rocketry, including the first stateside launch of a V-2 and the early tests of the Redstone, the first rocket to not only carry a live nuclear warhead, but—three years later—an American astronaut. A projectile from White Sands took the first photograph to reveal the earth’s curvature from space. Over the years the range has tested everything from bunker busters to rocket sleds to airborne lasers. It has hosted some notable visitors, including President Kennedy (who, in 1963, watched the army fire a Little John missile), David Bowie (who, in 1976, filmed parts of The Man Who Fell to Earth), and the Space Shuttle Columbia (which, in 1982, landed here because of flooding in California).

Today, a brochure from the test range details its mission: “We shake, rattle, and roll the product, roast it, freeze it, subject it to nuclear radiation, dip it in salt water, and roll it in the mud. We test its paint, bend its frame, and find out what effect its propulsion material has on flora and fauna. In the end, if it’s a missile, we fire it, record its performance, and bring back the pieces for postmortem examination. All test data is reduced, and the customer receives a full report.”

Later on the test morning, a lead-lined Sherman M-4 tank—complete with its own air supply—rolled into the blast zone to scoop up soil samples. Even though the ground immediately beneath the tower was paved to reduce the amount of earth picked up by the blast (which would become fallout), the fireball vaporized between 100 and 250 tons of sand, much of which rained back down as the radioactive glassy green residue dubbed Trinitite. The desert floor had been glazed for nearly half a mile. The tower was reduced to a red stain on the ground and a few fingers of rebar sticking up from its footings. The half-mile crater sloped down about ten feet—as if the earth had been pounded in, not blasted apart. When General Groves saw the hole, he was reported to have said, “Is that all?”

To preserve secrecy, the local area had not been evacuated beforehand. But food and water were stocked, and trucks and jeeps stood ready to move the population. Base camp was prepared to hold an extra 450 people. Other military installations could take in evacuees. The press was fed a cover story about the explosion of a munitions dump at Alamogordo Air Base.

Fallout monitors roved the countryside, taking readings; after one day, the cars themselves would become radioactive. The doctors were chiefly concerned about high-intensity exposure, not long-term consequences, which weren’t fully understood at the time. Two towns were nearly evacuated, but levels dipped once the “hot” cloud moved on.

Grazing land on the Chupadera Mesa, thirty miles to the northeast, was particularly contaminated. Fence posts were blanched white, as was the beard of a rancher. With their thick wool, the sheep fared better than the cattle, whose fur began to fall out about a month after the blast. (It would grow back without pigment.) The government bought four of the “atomic calves,” which—once Trinity’s secret was revealed in the weeks following Hiroshima—became popular in the press and were displayed across the state. When tests confirmed radiation was to blame, the other scabbed and splotched cattle were purchased and sent to Los Alamos and Oak Ridge, where they were bred, studied, slaughtered, and, in some cases, eaten.

One rancher would describe his land being covered with “light snow,” and a homeowner twenty miles away remembered flour-like dust remaining on the ground for four or five days. Ted Coker, who sold some of his afflicted cattle to the government, would recall the “funny” smell of the fallout; he was among a number of locals who eventually died of cancer.

Wind and rain concentrated the fallout that day. One area thought to be deserted—nicknamed “Hot Canyon” because the radiation was off the charts—was later was found to be inhabited by an older couple and their ten-year-old grandson, who drank the water that collected on their tin roof. Under various pretexts, scientists, doctors, and intelligence agents visited the family seven times in the two years after the blast. Reasons for the visits were never made explicit, even after the Trinity test became famous. The long-term health of overexposed civilians would not be monitored. Decades later, the doctor in charge of the Trinity medical group would admit, “We just assumed we got away with it.”

Only 20 percent of the bomb’s plutonium underwent fission; the other ten and a half pounds were pulverized and scattered over thousands of acres of desert. The half-life of plutonium is twenty-four thousand years. Inhaling only a small amount can lead to various deadly cancers.

At the zero mark, some 360 radioactive isotopes were born. Some died immediately, others lingered—a long chain of decay. Showing up fourteen minutes after the fact, strontium-90 is a soft metal with a twenty-nine-year half-life that is absorbed by plants and thus moves up the food chain, where it accumulates in bones, like calcium, and irradiates the body from within. (The isotope can move far and fast. In 1953, milk in New York was found to be tainted with strontium-90 from nuclear tests in Nevada.)

In 1947, a secret study from UCLA found yucca had recolonized the blast zone. The crater was filling in; it now dipped only six feet. But in places the Trinitite was still half an inch thick, and the soil radioactive to a depth of three and a half feet. Plutonium was on the ground for eighty-five miles. The scientists observed birds with deformed claws, rodents with cataracts, and oddly marked beetles. A study the following year found that the wind continued to spread the contamination.

For at least five years, the army would deny the existence of any fallout. Eight weeks after the blast—and a month after the bombing of Hiroshima and Nagasaki—reporters were invited to tour Ground Zero wearing little white booties to dispel the notion of lingering radiation poisoning in Japan. The journalists—from Time and Life and smaller local outlets—ate chicken and took home Trinitite souvenirs, while photographers shot pictures of Oppenheimer and Groves posing next to the remains of Ground Zero. Groves made his driver stand in the crater for half an hour to show just how harmless the site was. Two decades later, the man would be diagnosed with leukemia (which would prove fatal). The cause of cancer can be hard to determine, but before the driver died, the military granted him “service-connected” disability.

A survey in 1955 would be the last for a while. People would continue to be exposed by the gardens they grew and the animals they grazed (and watered with contaminated groundwater)—reaping their own radiant crop of milk, vegetables, chickens, goats, and cows. The government never intervened. A CDC report concluded in 2010, “It appears that internal radiation doses could have posed significant health risks for individuals exposed after the blast.”

At the gate, security officers check IDs and peer into cars. A tall metal sign warns in English and Spanish: AREA MAY BE CONTAMINATED WITH EXPLOSIVE DEVICES. More protesters hoist homemade signs. Some carry the names of people—even entire families—killed by cancer. A man in a dust mask holds the phrase GONE TOO SOON while another man waves the WINDS OF DESPAIR. A poster quotes the book of Revelation: I WILL DESTROY ALL THOSE WHO DESTROYED THE EARTH. A woman in a black-and-white Day of the Dead mask brandishes a sign that reads: REMEMBER DOWNWINDERS. Through my window, I ask if I can take her picture. She says, “Please do,” then shouts, “No more silence after seventy years!”

After the bombing of Japan, the U.S. government continued testing atomic weapons until 1992, setting off more than one thousand nuclear blasts, or an average of one every 16.5 days. (In 1962 alone—as a ban on atmospheric testing loomed—the military conducted ninety-eight tests.) Two hundred and ten of the explosions were aboveground, eight hundred and thirty-six were underground, and five were underwater, as the military experimented with bigger bombs, better designs, and different delivery mechanisms. The nukes blew up in the Pacific, the south Atlantic, New Mexico, Alaska, Mississippi, Colorado, and Nevada, where a government site held a staggering 925 tests (one hundred of which were atmospheric). These tests were witnessed by some 220,000 official participants—to say nothing of nearby civilian populations.

Citing local cancer rates that are six to eight times the national average, the protesters outside my car want New Mexicans to be included in the 1990 Radiation Exposure Compensation Act, which provides assistance to nuclear-test participants, uranium workers, and those downwind from the Nevada Test Site. A 2009 study by the Centers for Disease Control found that the Trinity test exposed parts of New Mexico to ten thousand times the radiation permissible today. The CDC has also reported that everyone born after 1951 in the continental U.S. has received radiation—in every organ and tissue—from now-banned nuclear tests, the residual fallout from which will eventually kill some eleven thousand Americans.

After the test, Groves sent word to Washington, which cabled the preliminary news to Potsdam, where Truman was meeting with allies Stalin and Churchill to discuss the end of the war. (The conference had already been delayed once in the hopes of having the bomb completed.) The next day, Washington provided further details using a real-estate code: “Doctor Groves has just returned most enthusiastic and confident that the little boy is as husky as his big brother. The light in his eyes discernible from here to Highhold and I could hear his screams from here to my farm.”

By the day after the test, fifty-seven Manhattan Project scientists had signed a petition asking Truman to consider the morality of using such a weapon. As the bomb was prepared for Japan, someone asked Oppenheimer why he was so glum; he replied, “I just keep thinking about all those poor little people.” Some scientists were told the bomb would spare hundreds of thousands of U.S. soldiers that could be lost in a ground invasion; they did not sign the petition. Nor did physicist Edward Teller, who had decided, “The things we are working on are so terrible that no amount of protesting or fiddling with politics will save our souls.”

The petition was circumvented by General Groves, who ensured it took a circuitous route to Washington, where the president wasn’t in residence, anyway.

The remnants of Jumbo rest in the parking lot just outside the test site. Once weighing 214 tons of banded steel, Jumbo was a $12 million, twenty-five-foot-long burrito-shaped container that originally was meant to house the Gadget—the idea being that, in the case of a fizzle, the precious plutonium would be saved. Fabricated in Chicago, Jumbo was the heaviest single object ever shipped by rail. The top-secret, canvas-covered behemoth wound its way on a flatcar from Ohio to Louisiana to Texas to New Mexico, where it was tugged across the desert on a custom sixty-four-wheeled trailer. By the time it arrived a few months before the test, Jumbo was deemed unnecessary. Eventually, it was stood on one end in a tower eight hundred yards from Zero. The structure was vaporized, but Jumbo remained. In fact, the army has had a hard time getting rid of the shell. An attempt to explode it in 1947 only popped the ends off; Jumbo was buried, dug up, and eventually dragged to the parking lot in 1979, where it now sits on its side. I walk through it—a tunnel with fourteen-inch-thick walls—and think of close calls. Had Jumbo been used, it would have become another 214 tons of fallout.

The soldiers sell brats and burgers, shirts and shot glasses. They are young and polite, calling everyone “sir” and “ma’am.” A record 5,534 visitors will show up today—even more than came twenty years ago for the fiftieth anniversary. (Later, I will shake hands with Brigadier General Timothy R. Coffin, the commander of the missile range, who stands tall in digital desert camo with his name—Coffin!—on his chest as he tells me each open house costs the army $60,000.) Meanwhile, people take selfies in front of radiation warnings posted on the chain-link fence. A film crew walks by, speaking Japanese. A woman’s ball cap reads WE NEED MORE HEROES beneath an American flag.

Three weeks after the Trinity test, on August 6, 1945, at 8:16 a.m., the Little Boy uranium bomb exploded above Hiroshima. Three days later, the Fat Man plutonium device was dropped on Nagasaki. Estimates vary, but by 1950 some 200,000 were dead at Hiroshima and 140,000 dead at Nagasaki. The latter blast was bigger—at twenty-two kilotons—but the damage was mitigated by the surrounding hills.

Truman was at lunch when he received news of the first successful atomic bombing; he told his tablemates, “This is the greatest thing in history.” In a radio address, he would explain to the nation, “The force from which the sun draws its power has been loosed against those who brought war to the Far East. . . . We have spent more than two billion dollars on the greatest scientific gamble in history—and we have won. But the greatest marvel is not the size of the enterprise, its secrecy, nor its cost, but the achievement of scientific brains in making it work.”

After the war, the U.S. Strategic Bombing Survey decided that dropping the bomb had not been necessary to defeat Japan. The country would have surrendered on its own most likely before November—even without any plans for an Allied invasion. (The firebombing of Tokyo earlier in the year had killed more people—and destroyed more square miles of city—than the immediate effects of either atomic blast.) Before Hiroshima, General Eisenhower told Secretary of War Henry Stimson that nuking Japan was “completely unnecessary” and “no longer mandatory as a measure to save American lives.” Many military voices echoed his thoughts. In a press conference six weeks after Nagasaki, General Curtis LeMay, the man in charge of the bombers, insisted that “the atomic bomb had nothing to do with the end of the war at all.”

One British physicist would remember General Groves saying—in 1944—that the bomb’s “real purpose” was “to subdue the Soviets,” our allies in the war. The following year, about a month before he became secretary of state (and more than two months before Hiroshima), James Byrnes explained to a Manhattan Project scientist that using the bomb would make “Russia more manageable in Europe.” In 1949, P. M. S. Blackett, a British Nobel Laureate and wartime advisor, wrote, “The dropping of the atomic bombs was not so much the last military act of the Second World War as the first major operation of the cold diplomatic war with Russia now in progress.” In August of that year, Russia tested its own atomic bomb, dubbed “First Lightning,” which fused the soil of the Kazakh steppes a startling blue-black.

Some say Truman didn’t really make a decision—that the bomb was so costly that it had to be used. He never doubted his actions and in fact wrote in 1963, “I would do it again.” In late 1945, when Oppenheimer told the president, “I feel I have blood on my hands,” Truman cut off dealings with him, calling him a “crybaby.”

For an atomic bomb, you can either split the nucleus of a heavy atom like uranium or plutonium through fission, or you can smash together two lighter nuclei, such as hydrogen, to form a larger nucleus. This process, called fusion, powers the stars—and, thanks to Edward Teller, today’s thermonuclear bombs. Many modern nuclear-weapon designers have backgrounds in astrophysics.

From the beginning, Teller was always more interested in the theoretically far more powerful fusion bomb, which he dubbed the “Super”—to the point that he dragged his heels on the Gadget. Fusion weapons are sometimes called hydrogen or thermonuclear bombs. The basic design—as envisioned by Edward Teller and Stanislaw Ulam—has leaked over the decades. A thermonuclear weapon is a staged device: a standard fission bomb implodes, the radiation from which compresses a secondary stage, which also undergoes fission—producing such temperatures that the hydrogen fuel caught between the two reactions must fuse. In other words, the legacy of Trinity—the implosion fission bomb—remains at the heart of every nuclear weapon.

After the Trinity test, Teller would ask Oppenheimer to support his quest for the thermonuclear bomb. Oppenheimer refused. In 1954, when the eccentric and left-leaning Oppenheimer got caught up in McCarthy-era security hearings, Teller would testify against him, leading to Oppenheimer’s clearance being revoked. The scientific community was scandalized. Wernher von Braun, the father of rocket science, would tell Congress: “In England, Oppenheimer would have been knighted” for his service to his country. The atomic cowboy would never again work for the government. He died of throat cancer in 1967.

During the war—while he and his colleagues worked on the Gadget—Teller would brood over bigger and bigger bombs. On a blackboard, he tracked his ideas for thermonuclear weapons, including one known simply as “the Backyard,” a planet-killer so destructive that it wouldn’t even have to be launched against one’s enemies, but instead could simply be detonated at home.

The U.S. first tested a full-scale thermonuclear device on an atoll in the Marshall Islands on November 1, 1952. The fireball alone from the 10.4-megaton blast stretched for three miles, while the mushroom cloud spread a hundred miles wide. The fallout from a thermonuclear bomb is believed to be even more lethal than the blast. (Many Marshall Islanders would die before being evacuated; thousands remain in exile today.) Nine months later, the Russians tested their first thermonuclear weapon, known as “the Sloika,” or layer cake. The force of these bombs can also be boosted by injecting the cores with tritium and deuterium, and by using casings that also undergo fission. The largest thermonuke ever tested was fifty megatons—or twenty-five hundred times the force of Trinity. Nobel Laureate I. I. Rabi once said, “The world would be better without an Edward Teller.”

Last summer, in the bookshelves in the den of my father’s childhood home in Gettysburg, I found a copy of the paperback How to Survive an Atomic Bomb, published in 1950, the cover showing a nuclear family (a term that predates Trinity: here, a father, mother, sister, brother) standing united to bravely face, if not a new shining day, then perhaps the initial blast, the front of their bodies lit by a searing light (in which case, they’re most likely goners). Written by a naval Senior Radiological Safety Monitor, the book promises no “scare talk” or rumors. It claims to deliver facts. (“The truth is bad enough—but nowhere near as bad as you probably think.”) The cover proclaims, “If there’s ATOMIC WARFARE this book may save your life!”

How to Survive an Atomic Bomb is written as an imaginary dialogue, a kind of nuclear catechism. (“What is the heat of the bomb like?” “Is it all right to smoke?”) The expert might patronize (“It’s pronounced ‘ee-VAK-u-ate’”), bully (“Use your head”), or be ludicrously unhelpful. (What to think about while you’re on the ground waiting for the blast? Try reciting jingles, multiplication tables, or—best of all—the steps to follow after an attack.) Radiation is like liquor: “A little bit won’t do you any harm, but a lot of it will.” The book covers three kinds of atomic clouds, the effects on livestock (because of their coloring, white leghorn chickens fare better than Rhode Island reds), and the results of certain doses of radiation. (“One morning you might look at your pillow and find that your hair had begun to fall out. . . . You’d also run a fever, and your bowels would run, and you’d feel rotten and ‘achey’ all over. You might even have bloody spots on your skin and slight bleedings in your mouth. . . . You might find that for a time you were unable to beget children, although you could still have sexual relations. All these troubles would go away in time.”) There are chapters for those living in apartments, houses, and the country. Stark illustrations show fools falling off a fire escape, a farmer lying in a furrow, and how a fedora might save half of a man’s face from the flash (“In time of war, if you work outdoors you should always be fully clothed”). There are several mistruths: “There is one fact you must remember—and it definitely is a fact. Not one person in Hiroshima or Nagasaki was killed or injured by lingering radioactivity.” Also: “Facts will help kill the fear that causes panic.”

I join the quarter-mile march to the fenced oval that is Ground Zero. An Asian woman drags a wailing little girl by the arm. The crowd circles the lava-rock obelisk, erected twenty years after the fact on the spot where the Gadget’s tower stood. A guy in a NASA shirt holds a yellow Geiger counter. (A brochure I received upon entering the range reminds me that “although radiation levels at Ground Zero are low”—no more than ten times the natural background amount—“some feel any extra exposure should be avoided.”) Trinitite is still easy to find. A sign threatens thieves with fines and jail. Some teens huddle around a large green pile, which they have collected and washed off with water. I spot a fair number of little kids, plus at least three or four babies. Ahead of me, a father struggles to push an infant in a stroller through the sand, from which europium, cesium, cobalt, strontium, and plutonium are currently emitting alpha, beta, and gamma radiation. (The last rays are stopped only by one inch of lead or eight of concrete.) Historical photos hang on the far fence. A bomb casing similar to Fat Man’s sits on a trailer. Later, I will ride a hot, dusty bus two miles to the ranch house where the scientists assembled the core. There, a guy will look to the mountains and say, “I figure it would make you goofy, being out here.” Inside the house, I’ll hear a voice from another room offer some kind of summary: “It’s just the power of nature, the power of God, whatever you want to call it.”

There is no doubt atomic blasts are aesthetically beautiful: incomparable and illicit expressions of nature’s hidden physics—the micro blown up to such a macro scale that something, or maybe everything, inside you is stirred. In time, awe gives way to a grim connoisseur-ship. As it is so often said, fear quickly becomes something like desire. I could watch the declassified films for hours. There are so many stunning details: how the air rushes forward—with the blast wave—then blows briefly backward as it is sucked up to form the towering mushroom. That’s how I feel watching these awful films: pushed and pulled—shocked, devastated, repulsed, but then drawn into the cloud.

I stumble across an amazing artifact from the National Archives: a black-and-white army film that contains the actual sound of the blast. I put on headphones and I’m at Yucca Flat, Nevada, in the early morning of March 17, 1953, for the Annie test of Operation Upshot–Knothole, which was open to reporters, who watched 7.5 miles away from “News Nob.” The announcer counts down to the flash, which is blinding. Thirty seconds of murmuring as the sixteen-kiloton fireball climbs. Oh, look at that. Oh boy, George. The cloud billows up. Woohoo! The announcer warns the shockwave will soon arrive. Suddenly, a shotgun blast that crescendos louder and louder to become a rolling thunder. When it has receded, a man shouts, “Holy shit!” Then he shouts it again.

There were tests in the desert and under the sea. Rows of burning trees whip one way, then the next. Plumes of roiling water toss battleships like toys in a tub. In an instant, the paint on a bus burns off before the smoking black frame is flattened by the blast. Heat sears rows of caged pigs wearing military uniforms, the exposed flesh meant to mimic human skin. (Imagine some twelve hundred porcine subjects in 1957 alone. Sheep and monkeys, too, the latter’s eyes taped wide open.) From inside a house, there’s a flash at the window; the blinds billow gently inward, then begin to smolder—before the entire structure is blown away. More interior scenes with nattily dressed mannequins posed in quiet domestic dramas: couples having cocktails, Junior riding the arm of the couch, Baby penned in front of the TV, Mom sitting dreamily at the window, moments before the panes impale her and slam her body across the room.

Supposedly named after everything from ghost towns to cheeses to prostitutes, a litany of tests runs through my head—Castle Bravo, Ivy Mike, Dormouse Prime, Little Feller, Diamond Fortune, Buster/Jangle, Tumbler-Snapper, Teapot, Wigwam, Redwing, Plumbbob, Romeo, Nougat, Gnome, Zucchini, Muenster, Diablo, Shasta, and Sugar—countless atomic suns born across the land. After a while, I can tell the clouds apart. Air tests, tower tests, underground tests—plus the atomic cannon (fired once). Soldiers would wait in trenches until the shockwave passed, then march into the blast zone and perform maneuvers beneath the fallout, while paratroopers floated down.

I watch the films; I sift through photographs. The images veer from the inconceivable to the insane. A live fish so radioactive that it made its own X-ray (the algae it had recently ingested glowing in its stomach). Marines clowning around for the camera, their hands “holding up” a mushroom cloud. Rows of VIPs in goggles and khaki shorts, watching from Adirondack chairs, their stern faces lit by the flash. A ballerina in a black leotard performing a pax de deux with the atomic cloud that climbs over her shoulder. Aerial views of the giant collapsed craters that pock the desert—like dimples on the moon—at what used to be known as the Nevada Test Site, north of Las Vegas. (The holes, carved out of the earth by more than eight hundred underground blasts, are still visited fondly by the aging scientists who made them.)

The height of bravado: a 1957 film of five volunteers standing in a huddle while a F-89 jet fires a two-kiloton nuclear air-to-air rocket that explodes 18,500 feet directly above them. A handmade sign stuck in the dirt reads GROUND ZERO. POPULATION: 5. The men shield their eyes with their hands; only one bothers to wear sunglasses. The center man delivers the play-by-play. After the blast, the men rejoice with hearty handshakes; one produces a cigar. The honey-voiced announcer calls the experience “just a wonderful thrill,” while the colonel effuses for those watching at home: “My only regrets right now are . . . that everybody couldn’t have been out here at Ground Zero with us.” All five men would eventually contract cancer.

The U.S. even detonated at least six nukes in space, shorting out terrestrial electronics and creating dazzling atomic auroras that played across the globe. In 1963, the Limited Test Ban Treaty banned nuclear testing aboveground, underwater, and in space. In 1992, the U.S. conducted its final underground test, though the Comprehensive Nuclear Test Ban Treaty—signed by President Clinton in 1996, but blocked by the Senate—still awaits ratification.

Maybe we all go a little mad in the desert of our imaginations. One morning, as the test date neared, Oppenheimer found everyone outside, staring at an unknown object blazing in the sky. The men raced for binoculars. A spy craft? Sabotage? From Albuquerque, Kirtland Air Force Base reported they had no planes able to intercept it. Oppenheimer recalled, “Our director of personnel was an astronomer and a man of some human wisdom; and he finally came to my office and asked whether we would stop trying to shoot down Venus.”

Later, in 1960, NORAD went on highest alert—99.9 percent sure of a nuclear attack—when a U.S. Air Force radar station in Greenland mistook the rising moon for a Siberian missile launch.

An arms race is a search for military high ground. A Study of Lunar Research Flights, Volume 1, issued from Kirtland Air Force Base on June 19, 1959, outlines a secret Air Force plan to detonate a nuke on the moon. The idea—officially known as Project A-119—was to offer a show of American strength in the face of Sputnik. (“Obviously . . . specific positive effects would accrue to the nation first performing such a feat.”) A young Carl Sagan contributed to the study, which outlines the scientific, military, and political gains in hundreds of pages of equations, measurements, tables, and arguments, all contextualizing the central madness: launching a nuclear missile at the moon. The report covers potential hazards in appendices such as “Survival Time of an Irradiated Population” and “Current Attitudes and Activities Regarding Biological Contamination of Extraterrestrial Bodies.” Volume two of the report remains classified, while other studies have been destroyed.

Thankfully, instead of nuking the moon, the U.S. decided to try to walk on it, which we did in 1969, as the Cold War fueled the American race to space. Two days before my visit to Trinity, at an Albuquerque restaurant, I met the last man to step onto the moon, Apollo 17 astronaut Harrison H. Schmitt, who spent more than three days in 1972 on the lunar surface. I asked Schmitt if he was familiar with Project A-119. “I hadn’t heard of that one,” he said, laughing. “Ah, just another crater.” Then he reminded me of another atomic detonation in New Mexico, an unsuccessful attempt in 1967 to use a nuclear bomb to frack a gas well in the northwest corner of the state. He laughed again. “Nukes don’t frack; they melt.”

Schmitt was ten when the Trinity bomb was tested. His family lived outside of Silver City, some 150 miles away, where he woke up to not one but two blasts that morning. (The second was a reflection—another echo.) The detonation occurred during a shift change at the mine where his father worked as a geologist, and Schmitt remembers him coming home for lunch and scoffing, “I don’t know what that was, but that was no ammo dump.” After the war, Schmitt would watch the V-2 contrails rise over White Sands. He would grow up to meet Wernher von Braun, Robert Goddard, and other space pioneers before eventually riding a Saturn V rocket from Florida to the moon.

In 1982, as a U.S. senator, Schmitt would help broker the settlement between the government and the David McDonald family, the last of nearly one hundred families whose land had been seized to make the Trinity test site and bombing range. The land was never returned to the ranchers, who had been undercompensated. In protest, David, eighty-one, and his niece, Mary, reoccupied their ranch—which included the old site of the Trinity base camp. Schmitt intervened in the armed standoff, explaining, “I just tried to encourage people to talk to each other.”

Over lunch, the spaceman and I discussed science in the desert—from the ancient Anasazi stargazers in Chaco Canyon to the Very Large Array radio telescope in the plains west of Socorro—and whether the U.S. has lost its will to explore. A geologist like his father, Schmitt is the only professional scientist to have landed on the moon. In the lunar rover, he explored nearly nineteen miles of the Taurus–Littrow valley, where he and his commander collected 243 pounds of material. Despite the grueling demands of the mission, Schmitt’s boyish enthusiasm shone through, just a giddy scientist at play. NASA videos show him running, bouncing, and skiing down hills, singing goofy songs (“I was strolling on the moon one day, in the merry, merry month of May—no, December!”), and begging Mission Control to let him hurl his geology hammer in the moon’s one-sixth gravity. Over lunch, he waxed on about the valley’s deep beauty, the slopes brilliantly illuminated against the black sky, where the earth always hung in the same position. At one point on the mission tapes Schmitt deadpans, “You seen one earth, you’ve seen ’em all.” He took the famous “Blue Marble” photograph, an image that is often credited with raising global consciousness and underscoring the fragility of our home planet. The horizontal tread of his footprints will stand on the moon for millions of years.

Most of all, Schmitt remains frustrated that we haven’t been back. His book, Return to the Moon, advocates the development of a program to collect lunar helium-3 as a source for fusion power plants on earth. He believes all interplanetary roads—settlements in space, tourist flights to Mars—lead through the moon. (“The moon’s the place to learn how to do it.”) He talked about what it would take for the U.S. to maintain its space dominance: a younger, nimbler space agency, for starters. (“Apollo was a young person’s program—the average age was around twenty-five.”) That said, he no longer thinks the government is the best driver of exploration. He favors private funding, though he’s wary of his state’s massive spaceport, telling me at one point, “They have stars in their eyes.”

What do you ask someone who has left this world behind? I can only imagine what Schmitt thinks when he looks at the night sky, or what he felt leaving the moon, knowing he would never be back. (“All of us knew we would get one shot, one mission. But it was beyond our imagination that the whole technology would be abandoned.”) During our lunch, he told me something startling. He said the reason scientists—including ones at my own university—continue to pore over samples he brought back forty years ago is that looking at the moon is a way of peering into our own vanished past. He explained, “The moon is the history of the earth that we can no longer see.” The moon is constant, its every experience written on its face. And what does the record reveal—what does creation look like? Schmitt raised his eyebrows: “It was extraordinarily violent.”

A man in a denim jacket describes molten Trinitite raining down and collecting in puddles on the ground. His name is Robert Hermes, and he’s a retired Los Alamos physicist. He has several chunks of Trinitite set out on a table before him, plus a sizable piece pinned to his hat. He holds up a tube of green beads he found in the ant sand this morning. (Anthills are notoriously radioactive, as the insects pile up Trinitite.) He says such glassy droplets appear worldwide after other big impacts, particularly extinction events. He rattles the tube. “They’re the same size as the beads they found off the Yucatán—where the asteroid hit that killed all the dinosaurs.”

What is it about vast, empty spaces that beckons the imagination? Why do we choose to fill them with the seeds of our destruction? The desert. The moon. Twin two-sided coins.

I grew up in a city, but I spent a few summers at a camp in New Mexico, and as a teen I camped in the Pecos Wilderness, not far from Los Alamos. I remember never having seen so many stars; they stretched over my head like a blanket—a sky composed of more light than darkness. Or so it seemed then. At that moment, I had a profound realization of what I had been missing—and how much of the universe I would never live to see. It was an idea at once sad and thrilling.

Now my daughter dreams of going into space (along with being a superhero and catching a fairy). She wants her mother and me to come with her, of course, because she’s only four. So we go to the Science Center and sit in rocket chairs and watch the monitors as we “blast off” into space. They say someone her age might grow up to walk on Mars.

The U.S. occupational radiation threshold (for those working with nuclear power, medicine, weapons) is more than double the international limit. Some critics want it raised even higher, arguing the damage done by radiation is not linear—that there is a level at which long-term exposure is safe. (These skeptics, such as Representative Lamar Smith, a Texas Republican who chairs the House Science, Space, and Technology Committee, would loosen regulations on nuclear industries.) Meanwhile, scientists have discovered a “bystander effect”: irradiate a single cell, and those around it will suffer. In other words, cells communicate. The damage spreads wider and wider, every one a casualty.

In total, I will spend an hour within the inner fence at Ground Zero, which means I will absorb somewhere between one half to one millirem—at most, a sixth of a chest X-ray, or the cosmic radiation one receives flying the red-eye across the country, or what we soak up in a year sitting in front of the TV. A webpage from the Nuclear Regulatory Commission will tell me I have shorted my life expectancy by a minute and twelve seconds. On my way out, I will bite down and feel grit in my teeth. I’ll try not to lick my dusty lips, or think about the half-life of plutonium. I’ll blow my nose, rinse my mouth, and spit once I’m back at my car. But long after I’ve showered and scrubbed and left Trinity behind, I will feel its dust in my nose and taste its dirt in my mouth.

I’m wary of the line I’m treading. I don’t want to fall too hard for the atomic mystique, or slip into radiophobia—romanticizing the danger of an often-misunderstood science. Nobody would wish all radioactive materials from the earth. Radiation warms the planet from without and within. Many things are naturally radioactive, from bananas to our own bodies. And I wouldn’t want to live without nuclear medicine—its imaging, scans, and treatments. I stood next to my daughter when she got her first X-rays—for a mysterious pain in her leg that was temporarily crippling but ultimately benign. Only a toddler, she asked, “Daddy, why don’t I get to wear a big apron?” I held her hand while the huge machine made its ugly noise over her tiny bare body, and I remember being grateful for pictures of the unseen.

Back inside the fence, a retired White Sands public affairs officer is sitting—in some official capacity, I imagine—on a stool from which hangs a sign promising FREE ANSWERS. A freckled girl wrapped in a blanket runs a green rock up to him. She smiles when he says, “Yes, that’s the stuff, all right.” Suddenly, a Japanese interviewer puts a microphone in his face. A cameraman is rolling. We all fall silent. The interviewer doesn’t smile, but asks, “What is purpose of opening the site? What do you want the people to know?” The answer man thinks for a moment, then says, “We want people to understand what happened, and why it happened, and then go away to make their own judgments.”

During the war, the average age at Los Alamos was twenty-seven. Over the years, many of the scientists would be gripped by nostalgia for the days when they were young and working on the bomb. Edward Teller would say, “In spite of the difficulties, I (and many others) consider the wartime years at Los Alamos the most wonderful time in our lives.” A British physicist recalled, “Here at Los Alamos, I found a spirit of Athens, of Plato, of an ideal Republic.” Nobel Laureate Hans Bethe said at Oppenheimer’s memorial service, “There were other wartime laboratories of high achievement. . . . But I have never observed in any one of these other groups quite the spirit of belonging together, quite the urge to reminisce about the days of the laboratory, quite the feeling that this was really the great time of their lives.” As one physicist remembered in 1970, “It was one of the few times in my life when I felt truly alive.”

Lately, a similar Cold War nostalgia has slipped into the national rhetoric, as politicians and pundits yearn for the less confusing world when it was just us versus them. How quickly we forget—and confuse simplicity with safety. I grew up a Cold War kid. In the 1980s, the threat of nuclear war was always in the background, like the TV. Among my childhood possessions, I recently found a 160-page booklet issued by the Department of Defense called Soviet Military Power. Packed with graphs, stats, war plans, and lavish illustrations of tanks, bombers, missiles, subs, and satellites, the book lingers over our enemy’s might with a lover’s eye. Today, I find the book unsettling. I picked up Soviet Military Power in 1987—the year it was published—when I was ten.

The day grows long. We have been reduced to a bunch of tourists milling about under military gaze. A small crowd stands around the obelisk, which is less of a focal point than a photo op. (We considered ourselves to be a powerful culture.) People approach warily, pose, then retreat. Nobody takes turns; everyone goes home with pictures of each other, which is as it should be. We’re all in this together, a kind of bystander effect. (This place is not a place of honor.) Beside the monument stands a fading footprint of concrete and rebar—the remains of a leg of the tower. I don’t think of the invisible rays that may or may not be killing us. (What is here is dangerous and repulsive to us.) We’re all dying anyway, one way or another, as the great clock counts down. (The danger is still present, in your time, as it was in ours.)

What is the half-life of memory? The observation bunkers, where Oppenheimer and the scientists fretted then rejoiced, are long gone. Creosote, yucca, and yellow grass are reclaiming the plain. At Ground Zero, the hot dust decays, leeching energy into the desert. The event moves into the mind, but we must hold onto the dead: Hiroshima. Nagasaki. The scientists and soldiers who tested and were tested upon. The rest of us standing downwind of history, ongoing casualties of a never-ending Cold War. We’ve come up with so many clever ways to wipe each other off the earth.

Standing here gives only a feeling of emptiness. Not necessarily despair, or sorrow, but absence. We’ve all come to Zero. No thoughts, no words—nothing remains. Complete devastation. And isn’t that the point of the bomb?

2015