Nuclear explosion

“ Apart from the gamma radiation ordinary light is emitted, some of which is visible and some of which is the ultra violet rays mainly responsible for flash burns. The emission of light starts a few milliseconds after the nuclear explosion when the energy from the explosion reaches the air surrounding the bomb. The observer sees then a ball of fire which rapidly grows in size. During most of the early time, the ball of fire extends as far as the wave of high pressure. As the ball of fire grows its temperature and brightness decrease. ”

“ One is to explode the bomb over deep water. In this case the close-in fallout amounts to between thirty and fifty per cent. This is because many of the water drops to which radioactive particles have adhered evaporate before they hit the ground. Over shallow water, however, if the fireball actually touches the bottom, the close-in fallout resembles the case of a land explosion and is again about eighty per cent or so. The close-in fallout for underground or underwater explosions will be even higher than for the surface explosions. ”

“ If such a reactor operates for half a year and then explodes and releases its radioactive content into the atmosphere, its radioactivity will be comparable to that of a hydrogen bomb. In one important respect such an accident would be worse than a hydrogen explosion. The nuclear explosive lifts most of its radioactive products to a high altitude and the poisonous activity gets dispersed and diluted before it descends. The activity from a reactor on the other hand will remain close to the ground and might endanger the lives of the people in an area of hundreds of square miles. ”

“ Not all the radioactivity which is made in the explosion contributes to the fallout, either local or world-wide. Some of the radioactive fission fragments (gamma emitters) have such short half-lives [11] that they actually disintegrate before the bomb has disassembled. A great many others disintegrate in the first few minutes while the atomic cloud is rising. The energetic beta and gamma rays released in these early, rapid disintegrations are stopped in short distances and merely add to the havoc at the scene of the explosion. ”

“ In nuclear explosions, about 90 percent of the energy is released in less than one millionth of a second. Most of this is in the form of the heat and shock waves which produce the damage. It is this immediate and direct explosive power which could devastate the urban centers in a major nuclear war.
Compared with the immediate colossal destruction suffered in target areas, the more subtle, longer term effects of the remaining 10 percent of the energy released by nuclear weapons might seem a matter of secondary concern. ”

“ Both the local and worldwide fallout hazards of nuclear explosions depend on a variety of interacting factors: weapon design, explosive force, altitude and latitude of detonation, time of year, and local weather conditions.
All present nuclear weapon designs require the splitting of heavy elements like uranium and plutonium. The energy released in this fission process is many millions of times greater, pound for pound, than the most energetic chemical reactions. ”

“ At the same time, one may precipitate almost all the activity near the explosion so that distant localities would not be seriously affected. It is conceivable, therefore, that radiological warfare could be used in a humane manner. By exploding a weapon of this kind near an island one might be able to force evacuation without loss of human life. ”

“ The time which has elapsed to reach this stage of the explosion depends on the bomb energy. If two explosions are compared, and the bigger one has a thousand times the explosive power of the smaller one, then the time needed to reach the extreme expansion of the fireball will be approximately ten times greater for the more violent event. In any case, a reasonably close observer has to use strongly absorbing glasses during this time if he is not to be blinded. For small bombs, the expansion of the fireball is too short to register. ”

“ The encounter between the fighter plane and the bomber may well take place in our own country over populated areas. This possibility would fill most people with alarm lest the population underneath the explosion should be hurt. Fortunately, in a recent nuclear test in Nevada, five well-informed and courageous Air Force officers demonstrated that there is complete safety to people on the ground. ”

“ One need not fear that a nuclear reactor might explode 154 like an atomic bomb. Nuclear explosives are very carefully constructed so that they can release a lot of energy in a short time. Nuclear reactors on the other hand are put together so as to make it possible that energy will be released only at a moderate rate. Some reactors if improperly handled may explode, but the violence of the explosion cannot greatly exceed that of a similar weight of high explosive. ”

“ The neutrons have much less damage effect than the gamma rays because they have a smaller intensity and also because they are strongly absorbed in air and therefore can penetrate only to relatively small distances from the explosion: at a thousand yards the neutron intensity is negligible. After the nuclear emission, strong gamma radiation continues to come from the exploded bomb. This generates from the fission products and continues for about one minute until all of the explosion products have risen to such a height that the intensity received on the ground is negligible. ”

“ All nuclear explosions cause light, heat and blast, which occur immediately. In addition, explosions that are on or close to the ground would create large quantities of dangerous radioactive fallout particles, most of which would fall to earth during the first 24 hours. Explosions high in the air would create smaller radioactive particles, which would not have any real effect on humans until many months or years later, if at all. ”

“ Liquid gas tanks exploded in Mexico City, killing 1,000 and leaving thousands more homeless. The Chernobyl nuclear reactor explosion sent nuclear fallout across Europe, increasing the risks of future human cancers. ”

“ In addition to protecting people from fallout radiation, most fallout shelters also would provide some limited protection against the blast and heat effects of nuclear explosions that were not close by. ”

“ The explosion was sure to be millions of times as powerful as ordinary chemical explosions involving the same quantity of exploding material, since the latter used only the electromagnetic interaction, while the former used the much stronger nuclear interaction.
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The first to think seriously of such a nuclear chain reaction was the Hungarian physicist Leo Szilard (1898-1964) . He was working in Germany in 1933 when Adolf Hitler came to power and, since he was Jewish, he felt it would be wise to leave Germany. ”

“ And along with the Russians, we're on our way to destroying the missiles and the bombers that carry 9,000 nuclear warheads. We've come so far so fast in this post-cold-war world that it's easy to take the decline of the nuclear threat for granted. ”

“ In 1949 the Soviets exploded their first nuclear bomb. In 1952 the British did the same; in 1960, the French; and in 1964, the Chinese.
Although many nuclear bombs have been exploded for test purposes, the two over Hiroshima and Nagasaki have been the only ones used in time of war. ”

“ One is that factories are located in cities, and these factories support the war effort. The other reason is that cities are centers of transportation through which the supplies of war materials pass. By destroying these centers the flow of the war supplies can be interrupted.
Nuclear warfare is likely to be quite different from past conflicts. The great concentration of firepower which a nuclear weapon represents makes it possible to attack on enemy anywhere, at very short notice. ”

“ These explosives also require a complex arrangement of detonators, explosive charges to produce an even and rapid compression of the core; sophisticated electronics to fire the explosives; a neutron initiator to provide initial burst of neutrons to start the nuclear reactions. ”

“ If we renounce nuclear weapons, we open the door to aggression. If we fail to develop clean explosives, we expose people to disaster from radioactive fallout in any serious military conflict. To our way of thinking these are weighty arguments in favor of continued experimentation and development of nuclear weapons. ”

“ The World Health Organization has concluded that a major nuclear war between the United States and the Soviet Union could leave 1.1 billion dead from immediate nuclear effects of the blast, fireball and radiation. Another 1.1 billion would be injured. Since medical facilities would be almost wiped out, most of the injured will die. The ultimate toll within a few months is estimated by this study to be more than 2 billion people or roughly half the world's population. ”

“ It has been estimated that an attack on U.S. population centers by 100 weapons of one-megaton fission yield would kill up to 20 percent of the population immediately through blast, heat, ground shock and instant radiation effects (neutrons and gamma rays) ; an attack with 1,000 such weapons would destroy immediately almost half the U.S. population. These figures do not include additional deaths from fires, lack of medical attention, starvation, or the lethal fallout showering to the ground downwind of the burst points of the weapons.
Most of the bomb-produced radionuclides decay rapidly. ”

“ This can, for obvious reasons, lead to serious instability in the overall system—most interesting systems cannot withstand the unbounded increase of any of their parameters without serious negative consequences. The basic engineering principles underlying the creation of nuclear weapons exploit this feature of positive feedback mechanisms: the destructive output of nuclear weapons results from the energy released during the fission of certain isotopes of (in most cases) uranium or plutonium. ”

“ Radiological dispersal devices, comprised of an explosive device with radioactive material, can be detonated without the need for the components of a nuclear weapon. The RDD can disperse radioactive material over an area of the battlefield causing effects from nuisance levels of radioactive material to life-threatening levels without the thermal and, in most cases, the blast effects of a nuclear detonation. For nuclear weapons effects see Appendix A.
[1-3] Table 1-1. Countries Possessing or Suspected of Possessing Nuclear Weapons
b. ”

“ Nuclear explosives have not been used in a similar way. The reason is the danger from radioactivity. Once we fully master the art of clean explosions peaceful applications will follow and another step will be made in controlling the forces of nature. ”

“ No instrument, not even a weapon, is evil in itself. Everything depends on the way in which it is used.
Public opinion has all but persuaded itself that nuclear weapons will be used not for a military objective but to terrorize and kill the greatest number of people. This is technically feasible. In fact, it does not even require the atomic bomb. For the last hundred years this possibility has been with us. Bacteriological warfare may cause widespread destruction. Yet no one has resorted to this horrible way of making war. ”

“ Any nuclear reactors anywhere make us vulnerable to aggression and fanaticism by politicians and terrorists — even if they don't have access to nuclear bombs.
When we even maintain a supply of nuclear bombs as a "deterrent," we are dangerously perpetuating the illusion that our safety and security lie in nuclear materials. ”

“ In a nuclear war, even in a limited one, the situation will probably be quite different. That noncombatants suffer in wars is not new. In a nuclear war, this suffering may well be increased further due to the radioactive poisons which kill friend and foe, soldier and civilian alike. ”

“ We are developing clean weapons which are effective by their blast and their heat, but which produce little radioactivity. Of course, blast and heat will do damage only near the point of detonation. Radioactivity may be carried by the winds and escape the control of man to a considerable extent.
It is clear that war is and always has been terrible. We refuse to believe that wars will always be with us but we cannot disregard the danger of war as long as the world is half free and half slave. ”

“ Also not included is the impact of tumbling; impact of glass shards from windows of vehicles or buildings; crushing deaths from building failure; or COSC casualties; thus causing underestimations on the number of patients. Further, there will be personnel who get radiation doses or burns and do not seek medical care.
e. A nuclear detonation may introduce new levels of destruction to the battlefield. There is very little experience with nuclear effects and there is certainly no experience with these weapons on a modern, highly technological battlefield. ”

“ We've had several incidents where nuclear weapons have literally fallen out of airplanes, literally just fallen through the bomb bays. Probably the most interesting one is the one that fell out of a strategic bomber in the Carolinas some years ago . . . . landed in Carolina in a swamp, and they looked all over for that nuclear weapon. ”

“ Protective measures could be based only on estimates and calculations. Furthermore, scientists were reasonably confident that the gun-type uranium-fueled device could be successfully detonated, but they did not know if the more complex firing technology required in an implosion device would work. Successful detonation of the TRINITY device showed that implosion would work, that a nuclear chain reaction would result in a powerful detonation, and that effective means exist to guard against the blast and radiation produced. ”