The Age of Radiance

by Craig Nelson

  Three weeks later, on May 2, 1945, Berlin surrendered.

  7

  The First Cry of a Newborn World

  AS El Camino Real followed the Rio Grande across the American Southwest, the river curved in a 120-mile bend, lengthening and complicating the journey with deep canyons, Apache assaults, and patches of quicksand—the original badlands. A well-known shortcut, well-known for being bleak and harsh, required at least three days of forced twenty-four-hour marching with no water. After Pueblo Indians, revolting against the Spanish, lost over five hundred souls in nine days traveling the route in 1680, the shortcut was named Jornada del Muerto—the Journey of Death. Here in July of 1945, Oppenheimer would test the Nagasaki plutonium gadget that inspired him to quote Hindu scripture (I am become Death), building a base camp that meant dust in the lungs, scorpions in the bed, and eighteen-hour workdays of 100°F. Twice, night-flying B-29 pilots mistook the camp for a practice target and bombed it.

  Frank Oppenheimer: “We spent several days finding escape routes through the desert, and making little maps so everybody could be evacuated.”

  Soldier Val Fitch: “In May, one hundred tons of TNT were exploded near the tower site as a calibration of some of the instrumentation. In view of what was to come later I doubt if the exercise was of any value, but at the time I thought that one hundred tons made an incredible explosion.”

  George Kistiakowsky deliberately transferred the bomb to the Jornada camp on Friday the thirteenth, and Hans Bethe filed his report “Expected Damage of the Gadget”:

  Comparison with TNT: The most striking difference between the gadget and a TNT charge is in the temperatures generated. The latter yields temperatures of a few thousand degrees whereas the former pushes the temperature as high as [tens of millions of degrees]. . . .

  The actual damage depends much on the objective. Houses begin to be smashed under shocks of 1/10 to 1/5 of an atmosphere. For objects such as steel supported buildings and machinery, greater pressures are required and the duration of the shock is very important. If the duration of the pressure pulse is smaller than the natural vibration period of the structure, the integral of the pressure over the duration T of the impulse is significant for the damage. If the pulse lasts for several vibration periods, the peak pressure is the important quantity. . . .

  Other Damage: The neutrons emitted from the gadget will diffuse through the air over a distance of 1 to 2 km, nearly independent of the energy release. Over this region, their intensity will be sufficient to kill a person.

  The effect of the radioactive fission products depends entirely on the distance to which they are carried by the wind. If 1 kg of fission products is distributed uniformly over an area of about 100 square miles, the radioactivity during the first day will represent a lethal dose (= 500 R units): after a few days, only about 10 R units per day are emitted. If the material is more widely distributed by the wind, the effects of the radioactivity will be relatively minor.

  Originally Groves planned to detonate Fat Man inside a 240-ton steel canister so that, in case of disaster, the plutonium could be rescued. But it was impossible to construct the bomb inside this containment shell, so instead they sealed the windows of a ranch bedroom with tape to reduce the dust and assembled it there.

  The Fat Man gadget, grungy and cobbled together, was composed of thirty-two implosion lenses weighing fifty-three hundred pounds, with an outer layer of 60 percent RDX (also known as cyclonite or hexogen, RDX was a popular industrial and military explosive in this era as it was more powerful than TNT), 39 percent TNT, and 1 percent wax, and an inner layer of 70 percent barium nitrate and 30 percent TNT, surrounding the split sides of the plutonium orb. Each lens was tethered by cloth-insulated wires that arched every which way to a Y-1773 detonator, which could be triggered so that all thirty-two would ignite precisely at the same time. Within the orb was the initiator of beryllium and polonium, already generating power and warm to the touch. When they tried aligning the orb’s halves inside Kisty’s lenses, however, they wouldn’t fit. No one could understand it. Then someone suggested that the plutonium had gotten warm in the car ride over and expanded, and if they waited a bit, it would contract back to its design specifications. This turned out to be the case.

  To raise Fat Man to its tower, Groves brought in a $20,000 winch, but everyone was so nervous that the Bomb’s five-ton weight would break the winch’s cable that soldiers used an untold number of mattresses to mound a fifteen-foot-high cushion on the linoleum-covered tower base. Here was the future of warfare, ominous in its bulging TNT and hurricane of ignition wires, protected by a hillock of beds.

  The desert floor was scattered with instruments, to measure as many of the results as possible: Light. Sound. Force. Radiation. Timing. Density. Blowback.

  As a much younger man, Oppenheimer had been introduced to poet John Donne by Jean Tatlock, the great love of his life who had committed suicide, and Trinity was named for two Donne poems, “Holy Sonnets XIV” and “Hymn to God, My God, in My Sickness”:

  Batter my heart, three-person’d God; for you

  As yet but knock; breathe, shine, and seek to mend;

  That I may rise, and stand, o’erthrow me, and bend

  Your force, to break, blow, burn, and make me new.

  As west and east

  In all flat maps—and I am one—are one,

  So death doth touch the resurrection.

  That day, Kitty gave Robert a four-leaf clover she’d found in their garden.

  A thunderstorm eased in on Saturday the fourteenth and lingered. Everyone looked at the high metal tower with its giant metal gadget in its nest of cabling and saw a perfect target for a lightning strike. “Oppenheimer was really terribly worried about the fact that the thing was so complicated, and so many people know exactly how it was put together that it would be easy to sabotage,” Dan Hornig, the electric trigger’s designer, said. “So he thought someone had better babysit it right up until the moment it was fired. They asked for volunteers, and as the youngest guy present, I was selected. . . . Little metal shack, open on one side, no windows on the other three, and a sixty-watt bulb with just a folding chair for me to sit on beside the bomb, and there I was! All I had was a telephone. I wasn’t equipped to defend myself. I don’t know what I was supposed to do. The possibility of lightning striking the tower was very much on my mind.” Guarding the tower’s base was control-room operator Joe McKibben, who fell asleep on the linoleum floor: “I started dreaming Kistiakowsky had gotten a garden hose and was sprinkling the bomb. Then I woke up and realized there was rain in my face.”

  Oppenheimer got the results of a dress rehearsal that had been done with a replica bomb and no plutonium in another canyon. It had failed, and he emotionally fell apart. An emergency meeting of Oppenheimer, Groves, Conant, and Kistiakowsky led to the three yelling at Kisty that his design was the problem. The Cossack insisted that his lenses would work.

  On Sunday the fifteenth, Hans Bethe called to say that the dummy test failed due to a calculation error that wasn’t applicable to Fat Man, and Trinity was rescheduled for July 16, at 4:00 a.m. Joe McKibben was working in the control room: “I was told that [Oppie] came in the door and observed me at the controls and went away. Just to see that I was sane.”

  The bad weather continued, and besides the lightning, the meteorologist warned that the wet air might short out the electrical triggers, and that winds might carry radiant fallout to nearby towns, including the mesa itself. Groves was so worried about sabotage that when the weatherman suggested another postponement, the general suggested he be hanged.

  Dan Hornig: “All the senior scientists who weren’t actually involved in the test had a betting pool. The betting ran from a complete dud to little explosions to middle-sized explosions. Just a few people were willing to bet that it would produce what it was supposed to produce with something like twenty thousand tons of TNT’s worth. There was a lot of skepticism.”

  Test director Kenneth Bainbrid
ge was incensed that Enrico Fermi was taking bets “on whether or not the bomb would ignite the atmosphere, and if so, whether it would merely destroy New Mexico or destroy the world,” talk that terrified the enlisted men. Ed Teller, meanwhile, was standing with Ernest Lawrence, his face covered in suntan lotion, his hands shielded with thick gloves, and his welder goggles in place. This, too, scared the nearby soldiers, who after all had no idea what to expect. Bainbridge, meanwhile, would become famous at this moment for telling Oppenheimer, “Now we’re all sons of bitches.”

  At 5:03 a.m., the arming party unlocked the switches and started the timer. Everyone was instructed to lie facedown in the sand, turning away from the bomb and burying their faces into their arms. No one did this.

  Across the base at 5:10 a.m., speakers and shortwave radios broadcast the voice of physicist Sam Allison announcing for the first time in history what is now known as a countdown. Allison: “I think I’m the first person to count backward.”

  At T-minus forty-five seconds, an automatic timing drum turned once a second, with a chime that struck at each turn. So there would be forty-four chimes before Allison bellowed, “Zero!”

  One of the photographers was Berlyn Brixner, who had been told to be ready with his sixteen-millimeter black-and-white movie camera to film something that had never before been seen, which would begin with the brightest light that had ever reached the earth in human history. Brixner at least saw the irony: “The theoretical people had calculated a ten-sun brightness. So that was easy. All I had to do was go out and point my camera at the sun and take some pictures. Ten times that was easy to calculate.”

  Civilian tech Jack Aeby had helped Emilio Segrè set up radiation instruments hanging on barrage balloons eight hundred yards from Fat Man; immediately after transmitting their results, they would be vaporized. Aeby had brought his own camera with him, filled with the new Anscochrome color slide film; his boss had gotten it through security. Jack set up a folding chair in the dirt and put on his government-issued welding goggles. He didn’t see that one of the lenses had a crack.

  At T-minus thirty seconds, a voltmeter indicated that the detonation circuit had achieved full charge. Those standing by Oppenheimer say he seemed to have completely stopped breathing. He held himself up by holding on to a wood fence post and stared at the tower.

  Then on July 16, 1945, at 05:29:45 mountain time, in a predawn desert, pitch-black and silent, a light exploded. That light, first white, then red, then purple, was visible on the horizon for 150 miles. As it reddened, it reduced in intensity enough to reveal a fireball raising a self-illuminated mushroom cloud of pulverized debris. The cloud rose 7.5 miles into the air, while the sky around it boiled purple from the ionization of the atmosphere. It smelled first like the desert, and then like a waterfall.

  Robert Serber: “At the instant of the explosion I was looking directly at it, with no eye protection of any kind. I saw first a yellow glow, which grew almost instantly into an overwhelming white flash, so intense that I was completely blinded. There was a definite sensation of heat. The brilliant illumination seemed to last for about three to five seconds, changing to yellow and then to red; at this stage it appeared to have a radius of about twenty degrees. The first thing I succeeded in seeing after being blinded by the flash looked like a dark violet column several thousand feet high. This column must actually have been quite bright, or I would not have been able to distinguish it. By twenty or thirty seconds after the explosion I was regaining normal vision. At a height of perhaps twenty thousand feet, two or three thin horizontal layers of shimmering white cloud were formed, perhaps due to condensation in the negative phase of the shock wave. Some time later, the noise of the explosion reached us. It had the quality of distant thunder, but was louder. The sound, due to reflections from nearby hills, returned and repeated and reverberated for several seconds, very much like thunder. A column of white smoke appeared over the point of the explosion, rising very rapidly, and spreading slightly as it rose. In a few seconds it reached cloud level, and the clouds in the immediate neighborhood seemed to evaporate and disappear. The column continued to rise and spread to a height of about twice the cloud level. There was no appearance of mushrooming at any height. A smoke cloud also was spreading near ground level. The grandeur and magnitude of the phenomenon were completely breathtaking.”

  Edwin M. McMillan: “At about thirty seconds, the general appearance was similar to a goblet; the ball I estimated to be about a mile in diameter and about four miles above the ground, glowing with a dull red; a dark stem connected it with the ground, and spread out in a thin dust layer that extended to a radius of about six miles. When the red glow faded out, a most remarkable effect made its appearance. The whole surface of the ball was covered with a purple luminescence, like that produced by the electrical excitation of air, and caused undoubtedly by the radioactivity of the material in the ball. This was visible for about five seconds; by this time the sunlight was becoming bright enough to obscure luminous effects. At some time near the end of the luminescence (I am not sure whether it was before or after) a great cloud broke out of the top of the ball and rose very rapidly to a height of about eight miles, expanding to a rather irregular shape several times as large as the ball. The whole spectacle was so tremendous and one might almost say fantastic that the immediate reaction of the watchers was one of awe rather than excitement. After some minutes of silence, a few people made remarks like ‘Well, it worked,’ and then conversation and discussion became general. I am sure that all who witnessed this test went away with a profound feeling that they had seen one of the great events of history.”

  Enrico Fermi: “After a few seconds the rising flames lost their brightness and appeared as a huge pillar of smoke with an expanded head like a gigantic mushroom that rose rapidly beyond the clouds probably to a height of thirty thousand feet. After reaching its full height, the smoke stayed stationary for a while before the wind started dissipating it. About forty seconds after the explosion the air blast reached me. I tried to estimate its strength by dropping from about six feet small pieces of paper before, during, and after the passage of the blast wave. Since, at the time, there was no wind, I could observe very distinctly and actually measure the displacement of the pieces of paper that were in the process of falling while the blast was passing. The shift was about two and a half meters, which, at the time, I estimated to correspond to the blast that would be produced by ten thousand tons of T.N.T.”

  Philip Morrison: “The column looked rather like smoke and flame rising from an oil fire. This turbulent red column rose straight up several thousand feet in a few seconds growing a mushroom-like head of the same kind. I noticed two deep thuds which sounded rather like a kettle drum rhythm being played some distance away. I remember the sound as being without any important high frequency components as cracks, etc.”

  James Conant: “The enormity of the light and its length quite stunned me. My instantaneous reaction was that something had gone wrong and that the thermal nuclear transformation of the atmosphere, once discussed as a possibility and only jokingly referred to a few minutes earlier, had actually occurred. . . . It looked like an enormous pyrotechnic display with great boiling of luminous vapors, some spots being brighter than others. Very shortly this began to fade and without thinking the [welder’s] glass was lowered and the scene viewed with the naked eye. The ball of gas was enlarging rapidly and turning into a [ten-thousand-foot-high] mushroom. It was reddish purple, and against the early dawn very luminous.”

  Next to him was Groves, grumbling as ever: “Well, there must be something in nucleonics after all.”

  General Farrell’s War Department report on the cataclysm in the American desert was released to the press the day after Hiroshima: “The whole country was lighted by searching light with the intensity many times that of the midday sun. It was golden, purple, violet, gray, and blue. It lighted every peak, crevasse, and ridge of the nearby mountain range with a clarity and beauty that can
not be described. . . . Thirty seconds after the explosion came first the air blast, pressing hard against the people and things; to be followed almost immediately by the strong, sustained, awesome roar which warned of doomsday. . . .”

  Kisty forgot to take cover when the ten suns exploded. He was knocked flat into the sand.

  Dick Feynman was sitting in a military truck and thought the windshield would protect his eyes, so he didn’t use any goggles. He guessed wrong and was temporarily blinded.

  One man at base refused to use the protective glass and burned his corneas. He was given morphine and was not expected to be permanently blinded.

  Jack Aeby had put his Perfex 44 camera on “bulb” and, in the dark before Zero, opened up the shutter, figuring that way he’d get a good image of the flash. Suddenly the light hit the cut in Aeby’s glasses and he saw a brilliant electric line. “I could see that crack for some time afterward. . . . I released the shutter, cranked the diaphragm down, changed the shutter speed and fired three times in succession. I quit at three because I was out of film.” Berlyn Brixner: “I was temporarily blinded. I looked to the side. The Oscura mountains were as bright as day. I saw this tremendous ball of fire, and it was rising. I was just spellbound! I followed it as it rose. There was no sound! It all took place in absolute silence. Then it dawned on me. I’m the photographer! I’ve gotta get that ball of fire.”