CHAPTER 9

The Resumption of Nuclear Tests

ON AUGUST 31, 1961, two months after my move to Boston, Premier Nikita Khrushchev announced the imminent resumption of atmospheric nuclear testing by the Soviet Union, thus unilaterally ending the three year moratorium on such tests. The U.S. was taken by surprise, as it often was by Soviet perfidy. Our nuclear talent was scattered, our facilities neglected or abandoned. Getting our act together again would entail another exhausting, competitive scramble.

THE SOVIETS SHOOT FIRST

The cavalier attitude of the Soviet Union toward a nuclear “gentlemen’s agreement” should have been evident from the very beginning of the moratorium. At midnight on October 31, 1958, all nuclear tests were to end. On the U.S. side, there was one shot still scheduled for October 31. It was a safety test in the best interests of everyone, but during the night the Nevada weather closed in. The test director called off the shot. The deadline came, and nuclear testing was over for the United States.

The Soviets viewed things differently. On October 31, 1958, two of their important missile-launched tests had yet to be conducted. On November 1 and again on November 3 they fired anyway, launching missiles with nuclear warheads aboard from the Kapustin Yar proving ground. The warheads detonated downrange, each with yields of ten kilotons. So much for the gentlemen’s agreement on days one and three.

Three years later, when Khrushchev announced his intention to resume nuclear testing, it was hardly a casual decision. On July 10 he summoned the leaders of the Soviet nuclear weapons program to a meeting in the Kremlin’s Oval Hall. He told them that nuclear testing would resume on September 1, with an announcement the day before. While that July 10 meeting constituted his final approval, there can be no doubt that weapons design, fabrication, and test planning had been underway for years.

During the sixty-five days that followed, from September 1 through November 4, the Soviets conducted fifty-nine shots at two test sites (Semipalatinsk and Novya Zemlya) plus four missile launches, with live warheads aboard, from Kapustin Yar.

During that same period, they conducted their first ever underground test, at Semipalatinsk on October 11.

They conducted their first missile-borne live firing from Novya Zemlya.

On October 27 they fired two space shots, timed for virtually simultaneous detonation.

Their tests included that nation’s first in the multimegaton category, including a fifty megaton burst that set a world record.

Even more disconcerting than the intensity of this test series was the radiochemistry of the bomb debris wafting across the Soviet borders and the electromagnetic signals given off by the tests. Atmospheric testing of nuclear devices is not a good idea. The merits of testing anywhere may be debated on policy grounds, but there can be no doubt that any nuclear event, be it test or accident, that releases irradiated materials into the atmosphere is bad for all of us. The venting of small amounts of short-lived isotopes may be harmless compared to the background radiation we all receive from the sun every day; the fallout from a few nuclear tests over a desert may be insignificant when compared to the increase in solar radiation many people accept willingly when they move from a coastal city, such as New York, to a mountain retreat, such as Denver; but such activities do have an impact on our environment. That is why containment vessels are built around nuclear power plants, and why the nuclear states agreed, in 1963, to ban any further testing of nuclear devices in the atmosphere.

However, in terms of the Cold War, atmospheric testing provided an important insight into the weapons programs of the closed Soviet society. We first learned that the Soviets had tested a nuclear device, and we learned what it was made of, solely on the basis of bomb debris analysis; we calculated the efficiency of Joe-1, and we noted its similarity to the first U.S. A-bomb. In the decade that followed, the technology of radiochemistry underwent significant improvement. The U.S. flew diagnostic aircraft, equipped with all sorts of filters and other instruments, around the edges of clouds thrown up by our own tests.

If one knew the makeup of a device beforehand, such radiochemical sampling could be helpful to the designer in diagnosing its operation. But collecting debris from Soviet tests was even more enlightening. Think of it as sampling the smoke from your neighbor’s chimney. The amount of unburned carbon coming out, the presence of sap or other materials, tells you whether he’s burning firewood or coal, whether he’s operating a large foundry or just staying warm, and whether his fire is well-tended or simply part of the interior decor. The U.S. got very good at flying around the edges of the Soviet Union, China, and other emerging nuclear states, sniffing for evidence of a test. The results gave us a clear view of the disasters awaiting if any of us made a mistake.

In addition to radiochemistry, the United States deployed a network of acoustic sensors around the world to listen for the sound waves emanating from huge explosions. The results could confirm the location, date, and approximate yield of any nuclear test. In the 1950s we also deployed electronic sensors to detect the electromagnetic pulse given off by any nuclear event. At first we just looked for the signal, again to determine the date, place, and size of its source. In time, however, we began to look for pulses within that signal. These could evidence two-stage tests, prima facie evidence of an H-bomb. The time interval between these pulses or spikes would indicate the size and nature of the secondary or thermonuclear explosion.

All of this technology was brought to bear when the Soviets announced the resumption of nuclear testing. The collected debris indicated a degree of design sophistication and test readiness far above what had been seen before. The American acoustic sensors confirmed the size and scope of the test series, but the evidence from the radiochemical and electronic sensors was frightening.

As reported by Charles J. V. Murphy in Life magazine, there were higher than expected amounts of transuranic elements in the bomb debris. That confirmed a new generation of two-stage, fission-fusionfission devices. Longer than expected primary-secondary interval times, gleaned from electromagnetic signals, indicated a new approach to secondary ignition. That, in turn, meant an increase in efficiency, more yield per unit weight, and thus a more threatening missile capability.

The Soviets were testing a whole new generation of weapons. And they were investigating the effects of one detonation on another in space; that is, the ability of a defending warhead to disable or destroy an incoming weapon. It was confirmation of a new antiballistic missile system that would soon ring Moscow.

When I talked with the designers of those devices a generation later, the scientists involved denied any long range scheme to defraud the United States. The July 10, 1961, Kremlin meeting was the first confirmation they had of a resumption of atmospheric nuclear testing. On the other hand, they admitted that they were just kids at the time. They did not know what was in the mind of the Politburo or their lab directors when the moratorium was started in 1958. They pointed out that in the Soviet system there were no alternative jobs. People could not leave Arzamas-16 to pursue academic or commercial work. One did what he was told, and those Soviet nuclear scientists were told to keep on designing. Some said that their environment relaxed for a few months after the 1958 moratorium started, but by the beginning of 1960 the pressure was back on. No Soviet laboratories were closed and no test ranges were abandoned after the 1958 halt, as was the case in the U.S. While there is no unequivocal proof, most American experts agree that planning for the Soviet test series of 1961 had to be at least two years in the making.

I was at Livermore on that fateful September 1, 1961, having returned to do some consulting with those still working on Oso.Within a day, the Kennedy administration authorized the resumption of underground tests in Nevada. But there was a great deal of hand-wringing in Washington about atmospheric tests. I gave some directions to my former assistants regarding Oso and agreed with A Division leader Carl Haussmann that I would try to be more helpful if atmospheric testing was resumed.

OPERATION DOMINIC

On October 17 an A Division physicist called to say that atmospheric testing was now being scheduled in the Pacific, though always subject to presidential reconsideration. On November 6, 1961, Edward Teller called the Avco-Everett Research lab director, Arthur Kantrowitz, to urge my release. The latter had been a Teller graduate student, and that call did it. In November, I returned to Livermore to assume responsibility for the design of an Oso device for testing in the Pacific during the following summer as part of Operation Dominic.

Oso was not a major program, and in the grand sweep of nuclear history, my contributions were not all that significant. The cybership Oso sailed too close to the black holes of uncertainty ever to be seen again, although some of the ideas involved came to fruition in other warhead designs a few years later. I relate here the events of 1961–62 only to give the reader a view of the incredible Livermore system.

Designing an item for test is quite different from doing paper studies. At an early meeting, I discovered that Teller had thought about my Oso approach earlier but couldn’t figure out how to make it work; how nice. Several younger physicists were returned to my team, but far more impressive was the enthusiastic support I received from the older scientists designated to serve under my direction.

George Maenchen, an expert on one of the hydrodynamic codes, became my assistant designer. Victor Karpenko, a fabulously talented engineer, was to build this device. Dick Adelmann was to make all the test arrangements, tend to logistics, and pay the bills. I was twenty-eight, and all of these gentlemen were substantially older, yet they followed me through the labyrinth of a nuclear design with an enthusiasm that characterized the glories of Livermore.

Computer time was indispensable to good design. My souvenirs of that spring show that John Nuckolls and I gobbled up almost all the available time. Detailed calculation of Oso with better tools showed that it would not work as planned. New IBM machines were being installed as we labored, meaning cables and men in suits everywhere.

On March 23, John Kennedy showed up. He understood the difficulties we faced and came to Berkeley to express his support. He and his key defense advisers first met with the leadership of the Los Alamos, Livermore, and Berkeley laboratories to exchange views on the importance of the upcoming U.S. tests. Then he met with a roomful of designers, engineers, and technicians, the men and women who were working around the clock for six months and who now had to move out to tropical, remote stations to carry out the tests. He gave a pep talk that still rings in the ears of those who were there. He pledged to take the political heat. Our obligation was to deliver the technology. Finally there was his appearance at UC stadium, where 80,000 people crowded the field, filled every seat, and stood in every aisle to glimpse the Kennedy magic. And he delivered. The people there, and all who heard him on radio and TV, felt that he was talking to them, about their country and the perils it faced.

Meanwhile, back at the lab, the days grew longer and the time remaining until the shot would take place grew shorter. By May the pressure was on to tell the logisticians the dimensions of my device so they could plan its carriage to target. We drove the engineers to the brink of insanity, partly by designing things that couldn’t be built—foam supports with zero density or plating one molecule thick—and by refusing to commit to a design freeze.

On May 24 there was a major Oso design review in the conference center. I had charts and wrote all over three panels of blackboard. My plans seemed to draw enthusiastic support, so when the meeting was over, engineer Karpenko asked if this was what I wanted built. I said, “Sure,” but in my heart I meant no. I planned to return to my office and the computers to tweak the design one more time. No such luck. Karpenko pulled out a pocket camera, photographed every chart and chalk mark, and thanked me profusely. We had just executed a design freeze.

The action shifted to Oak Ridge, where components were being conjured by Merlins of the machine shops. No design was too complicated, no tolerance too tight, no deadline too short for those artists. Whatever the designer wanted, he got, but in the process the glories of the AEC system—absolute control by and accountability of the designer—began to get scary. I was out there all alone.

I traveled to Oak Ridge to inspect some parts, returned to Livermore to give some talks about the shot, then returned to Oak Ridge for assembly of the secondary components. At first they just looked like so many pieces of dark brown metal, but Yakov Zeldovich, an elder of the second Soviet nuclear estate, knew better. When he saw similar pieces of uranium and plutonium, he could not help but feel that a multitude of human lives had been compressed into each gram: those of the prisoners who worked the mines, the technicians who inhaled the dust, and then the potential victims, if any of that metal ever went critical.

My next stop was Travis Air Force Base, to watch the primary being mated to the main device. Then off to Hawaii. At the Barber’s Point airfield on Oahu, I watched Oso being unloaded from its C-124 and inserted into the bomb bay of a B-52. Then I was off to Hickham Field and the flight to Christmas Island, base camp for the Dominic test series of 1962.

That spot was hardly a resort. It is not the Christmas Island located in the Indian Ocean with an extinct volcano and some residents, but an atoll, also known as Kiritimati, located in the Gilbert Islands, on the equator. The Tarawa battleground of World War II fame is the best known of the Gilberts. The United States had abandoned its Pacific test facilities as the moratorium wore on, but our British friends were less foolish, letting us make use of their outpost, inhospitable as it was. (In fact, Christmas Island, or Kiritimati, was the base camp, home for diagnostics, not the test site itself. The devices were dropped from aircraft a suitable distance away.) The Brits used Kiritimati to test their first H-bombs in 1957. The island is seventeen miles long and fourteen feet high. Everyone lived and ate in tents. There was no air-conditioning other than in the instrumentation trailers. Swimming was only possible in the morning, when the troops would throw grenades inside the chain-link underwater fence, killing off any sharks that had snuck in during the night. Entertainment was movies, the mess hall, and a bar known as the Snake Pit. There was little consumption of alcohol except in postshot celebration or remorse. I recall seeing no women on the island.

Nuclear tests are best conducted at dawn. This allows good photographic coverage of the expanding fireball, important to the diagnostics. A few moments later the skies start to lighten, allowing the diagnostic airplanes to see the cloud they are supposed to sample. We tend to get carried away by the physics, but the scope of the entire test operation was staggering. Just one small component of the test task force was Patrol Squadron 872. That Navy organization, which flew P-3s to collect radiochemical samples, consisted of over fifty officers and 250 enlisted men who operated ten aircraft out of Barber’s Point in Hawaii for the entire summer.

I awoke early on the morning of the shot, in part out of nervousness and in part because of the droning of the countdown director, “Mahatma,” running through his checklist over the loudspeakers. At 6:00 A.M., I climbed up “the hill,” a sandpile a few feet high, to get my coffee and doughnuts, and to watch. The B-52 started practice runs at 5:30 A.M. The drop took place at 6:30 A.M. at a spot seventeen miles away. It took sixty-six seconds from drop to bang, but it seemed like there was time to review the whole program, if not my whole life, as those seconds dragged by. They felt like sixty-six years. Then the unforgettable. Even though we were wearing black goggles, and even though the yield was much lower than expected, the sky was filled with light. When all seemed dark, we removed those goggles, only to be blinded all over again. The ball of fire was white, then took on incredible colors—yellows and purples fascinating the mind’s eye.

For that shot, and for others that week, the loudspeaker tried to warn of the approaching shock wave, but the greenhorns always forget about it. When the blast wave arrived, two minutes after the flash, coffee flew everywhere. Several fellows were knocked over. Emotionally, I was too, for there’s nothing in the human experience that in any way relates to the detonation of a nuclear device on the distant horizon, no matter how “small” or how far away. I cannot image what it would be like to be any closer.

There’s the light, a brightness that simply does not stop. People talk about a flash, but a thermonuclear detonation is not a flashbulb event. The sun starts to burn on earth; darkness seems never to return. There are the colors—purples and other hallucinogenic hues that confirm Shakespeare’s observation about the next world: “What dreams may come when we have shuffled off this mortal coil must give us pause.” There’s the heat. It makes no sense to the brain, because the explosion being observed is almost over the horizon, as far away as Baltimore is from Washington. Yet the first flash gives way to an oppressive, lingering heat whose persistence becomes unnerving. And then there’s the all-enveloping roar of the savage beast unleashed. As noted earlier, it takes a while, several minutes, for sound waves to get from detonation point to observer, assuming that observer is a lucky, peacetime scientist. So much else happened that the senses are numb. The first shock wave is not a crack or a pop, as one hears from a gun fired far away. It is the opening of a roar encompassing the senses, seeming to continue forever. I saw only a few such events, none of them an act of war. The rest of you have no idea how lucky you are to have missed this experience in the real world.

LIVERMORE IN THE REARVIEW MIRROR

The decision by the Livermore Laboratory’s founders to invest their money in computers and to invest the talents of their brightest physicists and mathematicians in code development gave Livermore its distinctive character from the day the lab was born. The 1950s generation there became the designers of most warheads for the strategic weapon systems fielded in the 1960s. Those, in turn, changed the map of American deterrence.

They also drew the attention of the Chinese intelligence services. The secrets apparently stolen from Los Alamos by Chinese agents during the 1990s were, for the most part, not drawings—they were computer codes, the software that would allow Chinese cyberskippers to explore the far reaches of thermonuclear technology on their own.

The thermonuclear division at Livermore was once led by Harold Brown, then Carl Haussmann, and then by Jack Rosengren. John Nuckolls and I worked there. I was only a rookie in that lineup, but that group constitutes an interesting sample. We did our best creative work in our late twenties and early thirties. Some of us went on to play important management roles at the laboratory. In time, Brown and Nuckolls became directors, Haussmann and Rosengren associate directors. Some went on to important national security jobs in Washington. Brown and I served as Secretaries of the Air Force. Brown became a Secretary of Defense; I became a Special Assistant to a President. Rosengren made good on Teller’s IOU to the Navy. By the summer of 1962 he had brought a new sense of order to the Polaris warhead program. Rosengren went on to become the Scientific Deputy Director of the Defense Nuclear Agency. Nuckolls led the way in the use of lasers, rather than A-bombs, to implode small pellets of thermonuclear fuel.

The National Ignition Facility now under construction at Livermore will focus 192 laser beams, 500 square feet of laser power, with a brief power level of a billion megawatts, on a capsule of thermonuclear fuel. When the National Ignition Facility starts operation, Nuckolls’s concepts will have replaced A-bomb primaries with 192 lasers.

Less than half of these five designers ever earned a Ph.D. in physics or any other discipline. Nuckolls, Haussmann, and I went to graduate school and acquired master’s degrees along the way, but we were too impatient to settle into the academic system.

We were fortunate that other more learned men and women gave us the ships to sail through cyberspace. It was a marvelous division of labor. We were lucky to be able to undo the damage done by the wise men, those visually challenged intelligence counselors, dreamy Nobel laureates, Soviet-trusting cabinet officials, and rigid bureaucrats. Those who led the United States into the sixties and the unpoliced moratorium should have been as suspicious of their Soviet competitors as we foot soldiers were, but that was not always the case.

When atmospheric testing ended in 1963, the U.S. once again had recovered. The world was safer from the airborne junk once deposited on them, but one more window into the closed Soviet society slammed shut. We would never again be able to glimpse the inner working of a Soviet nuclear weapon.

While I have many memories of those years, one week is indelibly etched into my mind. It began on that hot evening in June 1962 when I pulled into an earth-berm building on a remote corner of Travis Air Force Base in California. It was there that the Oso components were assembled and the final product was loaded onto a C-124, for shipment to Hawaii and mating with its B-52 host. I last saw Oso seventeen miles off Christmas Island in the Pacific. It disappeared in a flash, then a psychedelic sphere of many colors, that I will never forget. Twenty-eight-year-old kids do not get to do that very often.