At that moment, our aircraft emerged from between two cloud layers and down below in the gap a huge bright orange ball was emerging. The ball was powerful and arrogant like Jupiter. Slowly and silently it crept upwards Having broken through the thick layer of clouds it kept growing. It seemed to suck the whole Earth into it. The spectacle was fantastic, unreal, supernatural.
The resulting radioactive fallout might have been catastrophic, not just for the Soviet Union but for its neighbors. Fortunately, because of the height at which the device was detonated, the accompanying five-mile-wide fireball was repelled away from the surface by the force of its own shockwave and did not make contact with the earth, thus greatly reducing the amount of fallout.
But the results might easily have been very different. However, condemnation was instantaneous—not just from the United States and its allies, but from the whole world. Up to this point, the United States and the Soviet Union and Great Britain had carried out hundreds of open-air nuclear weapons tests. Andrei Sakharov, horrified not just by the Tsar Bomba but by the cumulative effects of the emissions of all of these tests, became a strong supporter of imposing limitations on these tests in future.
President John F. Courtesy John F. Kennedy Presidential Library and Museum. Sakharov had been told by Khrushchev to come up with a bomb that was more powerful than anything else tested so far. The Soviet Union needed to show that it could pull ahead of the US in the nuclear arms race, according to Philip Coyle, the former head of US nuclear weapons testing under President Bill Clinton, who spent 30 years helping design and test atomic weapons.
And then it did a large number of tests in the atmosphere before the Russians even did one. The original design — a three layered bomb, with uranium layers separating each stage — would have had a yield of megatons — 3, times the size of the Hiroshima and Nagasaki bombs. The Soviets had already tested large devices in the atmosphere, equivalent to several megatons, but this would have been far, far bigger.
Some scientists began to believe it was too big. Before it was ready to be tested, the uranium layers that would have helped the bomb achieve its enormous yield were replaced with layers of lead, which lessened the intensity of the nuclear reaction.
The Soviets had built a weapon so powerful that they were unwilling to even test it at its full capacity. And that was only one of the problems with this devastating device. And, if the bomb was as powerful as intended, the aircraft would have been on a one-way mission anyway.
The power of the bomb persuaded nuclear physicist Andrei Sakharov to renounce nuclear weapons Credit: Science Photo Library. Even where nuclear weapons are concerned, there can be such as thing as too powerful, says Coyle, who is now a leading member of the Center for Arms Control and Non-Proliferation, a think tank based in Washington DC.
Von Hippel agrees. Things moved in a different direction — increasing missile accuracy and multiple warheads. Tsar Bomba had other effects. Von Hippel says that Sakharov was particularly worried by the amount of radioactive carbon 14 that was being emitted into the atmosphere — an isotope with a particularly long half-life. Sakharov worried that a bomb bigger than the one tested would not be repelled by its own blastwave — like Tsar Bomba had been — and would cause global fallout, spreading toxic dirt across the planet.
Sakharov become an ardent supporter of the Partial Test Ban, and an outspoken critic of nuclear proliferation and, in the late s, anti-missile defences that he feared would spur another nuclear arms race. If you liked this story, sign up for the weekly bbc.
Apocalypse Week Weapon. The monster atomic bomb that was too big to use. Share using Email. By Stephen Dowling 16th August In , the Soviet Union tested a nuclear bomb so powerful that it would have been too big to use in war.
And it had far-reaching effects of a very different kind. Since the bombs were detonated at a height of some metres above the ground, very little of the fission products were deposited on the ground beneath.
Some deposition occurred however in areas near to each city, owing to local rainfall occurring soon after the explosions. This happened at positions a few kilometres to the east of Nagasaki, and in areas to the west and north-west of Hiroshima. For the most part, however, these fission products were carried high into the upper atmosphere by the heat generated in the explosion itself. The majority would have decayed by the time they landed around the globe.
In Hiroshima, of a resident civilian population of , it was estimated that 45, died on the first day and a further 19, during the subsequent four months. In Nagasaki, out of a population of ,, on the first day 22, died and another 17, within four months.
Unrecorded deaths of military personnel and foreign workers may have added considerably to these figures. It is uncertain what proportion of these , deaths, or of the further deaths in military personnel, were due to radiation exposure rather than to the very high temperatures and blast pressures caused by the explosions — 15 kilotons at Hiroshima and 25 kilotons at Nagasaki. From the estimated radiation levels, however, it is apparent that radiation alone would not have been enough cause death in most of those exposed beyond a kilometre of the ground zero below the bombs.
Most deaths were from blast injuries or burns rather than the radiation. Beyond 1. In comparison, during the period of February to August , the US bombing of Japanese cities — notably Tokyo, Nagoya, Osaka and Kobe — by Bs delivered about kilotons of high explosives and incendiaries to urban areas in hundreds of raids, resulting in a large number of deaths and causing widespread destruction.
Some 80, to , people were killed in a single bomber raid on Tokyo. About 80 square kilometers of those four cities was destroyed in ten days during March.
Overall 67 Japanese cities were partly destroyed, , people were killed and 5 million more made homeless. To the , deaths from the blast or acute radiation exposure at Hiroshima and Nagasaki have since been added those due to radiation induced cancers and leukaemia, which amounted to some within 30 years, and which may ultimately reach about Some 93, exposed survivors were still being monitored 50 years later.
There was an increase in leukaemia beginning about two years later and peaking at four to six years later, and other cancers beginning about ten years later. There was no evident to suggest an increase in leukaemia at less than mSv acute dose. At an acute dose of mSv, an increased cancer risk of 1. There was concern about ingestion or inhalation of radionuclides, but fires released far higher levels of non-radioactive carcinogens.
Additionally, no genetic damage has been detected in survivors' children, despite careful and continuing investigation by a joint Japanese-US foundation. The major source of exposure in both cities was from the penetrating gamma radiations, and to a lesser extent from the neutrons mostly at Hiroshima , emitted during and shortly after fission. There were two further, and smaller, sources of exposure. One, already mentioned, was due to the 'black rain' which fell in some areas, carrying down radioactive materials from within the rising cloud of fission products.
The exposures due to these depositions are in general estimated to have been small, but some increased activity from the fission product radionuclide caesium remained detectable for many years in soil and farm products in the Nishiyama district east of Nagasaki. The second additional form of exposure resulted from the effect of neutrons in inducing radioactivity in various stable chemical elements such as in iron or concrete structures or roofing tiles.
The total absorbed doses of radiation from these activation products are estimated to be less than one per cent of that from the neutrons which induced them. They could however have caused a significant exposure of people who entered the city within a few days of the explosions. The atmospheric testing of some nuclear weapons up to caused people to be exposed to radiation in a quite different way.
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