It rained that night in a stretch of New Mexico desert the Spanish had named the Jornada del Muerto — the Journey of the Dead Man. Lightning walked the mountains around the test site. On a hundred-foot steel tower, wired with detonators and packed with more than two tons of conventional explosive machined into lenses around a sphere of plutonium no bigger than a softball, sat the device the scientists called, with deliberate flatness, the gadget.
A direct strike on the tower would have been a catastrophe of a particular kind: not the explosion they wanted, but a stray one, scattering the most expensive substance on earth across the sand. The test was set for four in the morning. The storm refused to cooperate.
“I Will Hang You”
The man who had to decide was General Leslie Groves, the Army engineer who ran the entire bomb program and had no patience for delay. His chief meteorologist, a civilian named Jack Hubbard, had promised a window of calm before dawn — a narrow one, between five and six. Groves had told him what would happen if he was wrong: “I will hang you.”
Groves and Robert Oppenheimer, the physicist who directed the laboratory at Los Alamos and had named the test Trinity, walked together in the rain. Oppenheimer was strung thin — chain-smoking, down to a frame that barely held his suit. Groves stayed close to him, the way you stay close to a man you are not sure will hold together. Around 4:45, the rain eased. Hubbard’s window was opening. The count was reset for 5:29.
The unease was not only about the weather. Enrico Fermi, one of the great physicists of the century, had been offering wagers to anyone nearby on whether the blast would ignite the atmosphere itself — and if it did, whether it would merely incinerate New Mexico or the whole planet. The calculation had been run and the answer was no. Fermi was, by most accounts, joking. But he was the kind of man whose jokes made other men quiet.
There was a more sober pool, too. The scientists had bet on the yield — how big it would be, measured in tons of TNT. Oppenheimer, pessimistic to the end, put it at 300 tons. Edward Teller guessed high, at 45,000. Isidor Rabi, arriving late, took the only number left in the pool: 18,000 tons. Kistiakowsky, the explosives expert, was so confident the implosion would work that he bet Oppenheimer a month’s salary against ten dollars.
Zero
In the final minutes the men were told to lie face down with their feet toward the tower and to look, if they looked at all, through squares of welder’s glass. The bunkers stood ten thousand yards out; another group watched from a hill twenty miles away, where Teller smeared suntan lotion on his face in the dark and passed the bottle around. The countdown came over the loudspeakers. At the control bunker Oppenheimer held onto a post and barely breathed.
At 5:29 in the morning, the desert turned to light.
It came before the sound — a flash with no warmth of dawn in it, white going to gold to violet, brighter by many times than the noon sun. It lit every peak and crevasse of the nearby mountains with a clarity, Brigadier General Thomas Farrell wrote, “that cannot be described but must be seen to be imagined.” A ball of fire climbed and mushroomed and rose past ten thousand feet, pulling a column of debris up behind it; the cloud would go on climbing for minutes, to some 38,000 feet. The hundred-foot steel tower simply ceased to exist — the steel, Groves reported, was evaporated, leaving stumps where its four legs had been sunk in concrete.
Then the heat reached the distant observers, and a long while after that, the sound: a roar that rolled off the mountains and came back, which Farrell called a warning of doomsday that made the men feel they were “puny things” who had dared to “tamper with the forces heretofore reserved to The Almighty.” The light was seen 180 miles away, at Albuquerque and Santa Fe and El Paso. The shock broke windows 120 miles off and was felt by people at least 160 miles from the tower.
Fermi, characteristically, was already working. As the blast wave passed he let small scraps of paper fall from his hand and watched how far the wind of it carried them — about two and a half meters. From that, on the spot, he put the yield near 10,000 tons of TNT. The radiochemical analysis put it at 18.6 kilotons, the official 1945 figure at 21, and a 2021 reanalysis nearer 25. Fermi had come in low by more than half — working, in the desert dark, with torn paper. Rabi, with his lonely guess of 18,000, won the pool.
The Sons of Bitches
The reactions did not match the moment, because nothing could. Men cheered. Some wept. Some shook hands as if at the end of a long shift. Kistiakowsky, five miles out, was knocked flat by the blast wave; he picked himself up, found Oppenheimer, slapped him on the back and said, “Oppie, you owe me ten dollars.” Oppenheimer opened his wallet, found it empty, and told him he would have to wait. He paid later, back at Los Alamos, and signed the bill.
Kenneth Bainbridge, the physicist who had run the test site and chosen the spot, walked over to Oppenheimer. What he said has lasted because it was the least poetic thing anyone said that morning, and maybe the truest: “Now we are all sons of bitches.”
Oppenheimer’s own famous line — that a verse from the Bhagavad Gita came to him, “Now I am become Death, the destroyer of worlds” — he gave years later, to a film crew, and it has the polish of something refined in memory. His brother Frank, standing beside him, was asked what was actually said and could only offer something plainer: “I think we just said, ‘It worked.’”
What Was Left
Where the tower had stood, the heat had been enough to melt the desert sand into a sheet of pale green glass, a centimeter or two thick and faintly radioactive, that scientists would name trinitite. The bomb had gouged less than people expected — a shallow depression rather than a proper crater — but Groves reported a circle twelve hundred feet across from which every trace of vegetation had vanished.
The official word given out was that a remotely located ammunition magazine, loaded with high explosive and pyrotechnics, had blown up — no loss of life, nothing to see. The real news went that same day in the language of a surgery report: “Operated on this morning. Diagnosis not yet complete but results seem satisfactory and already exceed expectations.” It reached Secretary of War Henry Stimson at Potsdam, where President Truman would sit down across a table from Stalin for the first time the next morning. Groves’s full account of what had happened in the desert took five days to reach him; when it did, Stimson read all fourteen pages aloud to Truman behind a closed door. Churchill saw the difference at once. “When he got to the meeting after having read this report, he was a changed man,” he told Stimson. “He told the Russians just where they got on and off and generally bossed the whole meeting.”
Three weeks later, a uranium bomb of a different and untested design fell on Hiroshima. Three days after that, a plutonium bomb — the gadget’s twin, the design proven that morning in the desert — fell on Nagasaki.
The rain had cleared by sunrise over the Jornada del Muerto. The desert was quiet again, the way it had been for a very long time.