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THE KILLING STAR
Had Mary Shelley or Edgar Allan Poe been born into the mid-twentieth century, they would never have had to invent horror.
For the Japanese scientists who first ventured into the still-radioactive hypocenters of Hiroshima and Nagasaki trying to understand what had occurred, the most fearsome deaths were the quickest. On a bridge located in central Hiroshima, a man could still be seen leading a horse, though he had utterly ceased to exist. His footsteps, the horse’s footsteps, and the last footsteps of the people who had been crossing the bridge with him toward the heart of the city were preserved on the instantly bleached road surface, as if by an accidental new method of flash photography.
Only a little farther downriver, barely 140 steps from the exact center of the detonation, and still within this same sliver of a second, women who were sitting on the stone steps of the Sumitomo Bank’s main entrance, evidently waiting for the doors to open, evaporated when the sky opened up instead. Those who did not survive the first half-second of human contact with a nuclear weapon were alive in one moment, on the bank’s steps or on the streets and the bridges—hoping for Japan’s victory or looking toward defeat, hoping for the return of loved ones taken away to war, or mourning loved ones already lost, thinking of increased food rations for their children, or of smaller dreams, or having no dreams at all—and then, facing the flash point, they were converted into gas and desiccated carbon and their minds and bodies dissolved, as if they had been merely the dream of something alien to human experience suddenly awakening. And yet the shadows of these people lingered behind their blast-dispersed carbon, imprinted upon the blistered sidewalks, and upon the bank’s granite steps—testament that they had once lived and breathed.
On that sixth day of August 1945, no one who conceived, designed, or assembled the Hiroshima bomb knew where uranium nuclei came from, or what science had actually achieved. Not Oppenheimer or Urey, Alvarez, or even Einstein would have believed that they had resurrected something from the remote past, from a time and a place seldom encountered in human thought. Each of the uranium-235 atoms at the bomb’s core had been forged more than 4.6 billion years earlier, in the hearts of supernovae. The core was assembled from the ash of stars that had lived and died long before the oldest mountains of the moon were born. Mined and refined to better than 83 percent purity, and brought together in precisely the right geometry, the primordial remnant of Creation was coerced to echo, after ages of quiescence, the last shriek of an imploding star. In all its barest quantum essentials, what happened above Hiroshima that morning—and three days later in Nagasaki, in a separate, plutonium cauldron, filled with the by-products of a uranium reactor—signified the brief reincarnations of distant suns.
None of the men who worked this strange alchemy understood yet that the carbon flowing within their veins was, like uranium, the dust of the stars. Nor did they know that the nuclei of carbon and uranium could possibly conceal anything much smaller than the diameter of a proton. Indeed, Einstein and Oppenheimer refused even to acknowledge that such quantum worlds existed. They therefore did not know what neutrons were made of or precisely how cracks in space-time—cracks in the universe itself—permitted matter to become energy. So primitive was their understanding that it might have been compared to the thought processes of a Neanderthal discovering napalm. In like manner, the scientists never suspected that the forces they unleashed bridged their day with the origin of the universe and bridged mega-time with the travel time of light across the diameter of a proton. Though they knew next to nothing about how their briefly created echo from the past worked, next to nothing was enough.
INEVITABLY, SOMEONE WAS BOUND to be standing below Point Zero. This peculiar distinction fell to a thirty-five-year-old widow and a half-dozen monks. Mrs. Aoyama had sent her son Nenkai away to school a half hour earlier than usual—which was why history was to claim the boy as the sole surviving resident from the neighborhood. The Aoyama home was attached on one side to a Buddhist temple with which the family shared and maintained a large vegetable garden. By 8:15, Mrs. Aoyama was probably working in the garden with her neighbors, just as she worked with them every morning. If so, no one was nearer the actual zero point, or more openly exposed, than Mrs. Aoyama and the monks.
Overhead, the Dome of Hiroshima’s Industrial Sciences Building pointed straight up into the center of the detonation. The temple garden in which Mrs. Aoyama toiled was located immediately adjacent to what would become known to future generations as "the Peace Dome." During that final split second before Moment Zero, Mrs. Aoyama and the monks lived on the cusp of instantaneous nonexistence, on the verge of dying before it was possible to realize they were about to die. At the moment the bomb came to life, before a globe of plasma could belly down to ground level, the top millimeter of the Dome’s metal cladding would catch the rays from the bomb and liquefy instantly, then flash to vapor. Bricks and concrete, too, were on the verge of developing a radiant, liquid skin.
Unlike the man leading a horse across the nearby "T" Bridge, Mrs. Aoyama could not possibly leave a permanent shadow on the ground. From the moment the rays began to pass through her bones, her marrow would begin vibrating at more than five times the boiling point of water. The bones themselves would become instantly incandescent, with all of her flesh trying simultaneously to explode away from her skeleton while being forced straight down into the ground as a compressed gas. Within the first three-tenths of a second following the bomb’s detonation, most of the iron was going to be separated from Mrs. Aoyama’s blood, as if by an atomic refinery. The top few millimeters of soil, as they converted to molten glass, would be shot through with such high concentrations of iron that, had the greenish-brown layer of glass been permitted to slowly cool, it would have been hidden beneath a sheet of carbon steel; but a slow and stately cooling was not to be. By the time the sound of the explosion reached her son Nenkai two kilometers away, all the substance of his mother’s body, including blood-derived iron and calcium-enriched glass, would be ascending toward the stratosphere to become part of the strange radioactive thunderstorms that were to chase after Nenkai and the other survivors.
On the south side of town, about four city blocks beyond Mrs. Aoyama and the monks, Toshihiko Matsuda was about to leave his shadow on a wall in his mother’s garden. He appeared to be bending down to pick a piece of fruit or to pull out a weed. During the next few milliseconds, the wall behind Toshihiko would be flash-printed not only with his shadow, but also with the ghost images of the plants that surrounded him (and which would provide his skin with some small measure of flash protection). On the wall print, at the moment of the bomb’s awakening, could be seen the shadow of a leaf that had just detached from its vine and, though falling, would never reach the ground.
From the Aoyama and Matsuda house holds to the shrimp boats in the harbor, human nervous systems were simply not fast enough to register how quickly the dawn of atomic death burst toward them on that August morning. In the beginning, it had all unfolded from the realm of nanoseconds. Within the core of the reaction zone, approximately 560 grams (or 1.2 pounds) of uranium-235 began to undergo fission before the compressive, shotgun-like forces designed to start the reaction, and to hold it briefly together, were overwhelmed by forces pushing it apart. Three times heavier than gold (at the moment of compression), every ounce of the silvery, neutron-emitting uranium metal occupied three times less volume than gold. The active, business end of the bomb was therefore astonishingly small, occupying one-third of a golf ball’s volume. The total volume of reacting uranium measured slightly more than two level teaspoons. Within that 1.2-pound, two-teaspoon volume, a sample of almost every element that had ever existed during the entire lifetime of the universe was instantly re-created, and many were just as quickly destroyed.
After only one-hundred-millionth of a second, the core began to expand and the fission reaction began to run down. During this ten-nanosecond interval, the first burst of light emerged with such intensity that even the green and yellow portions of the spectrum could be seen shining through the bomb’s steel casing as if it were a bag of transparent cellophane. Five hundred and eighty meters (1,900 feet) below, no creatures on the ground could see this. During the first ten nanoseconds, light from the core traveled only three meters (about ten feet) in all directions. Fission reactions occurred within time frames so narrow that they bracketed the speed of light. Thus, to anyone located more than ten feet away, the bomb itself, though light was now shining through it, seemed to be hanging perfectly intact above the city. Directly below, Mrs. Aoyama was still alive and completely untouched by the flash.
One ten-millionth of a second later, a sphere of gamma rays, escaping the core at light speed, reached a radius of 33 meters (108 feet), with a secondary spray of neutrons following not very far behind. Between the gamma bubble and the newly formed neutron bubble, electrons were stripped from every atom of air and accelerated toward the walls of the larger gamma sphere. A plasma bubble began to form, producing a thermal shock that spiked hotter than the Sun’s core and glowed billions of times brighter than the surface of the Sun.
Within this atomic f...
