Sergey LESKOV
On August 12, 1953, the world's first hydrogen bomb was tested at the Semipalatinsk test site. This was the fourth Soviet nuclear weapons test. The power of the bomb, which had the secret code “product RDS-6 s,” reached 400 kilotons, 20 times more than the first atomic bombs in the USA and USSR. After the test, Kurchatov turned to 32-year-old Sakharov with a deep bow: “Thank you, the savior of Russia!”
Which is better - Bee Line or MTS? One of the most pressing issues of Russian everyday life. Half a century ago, in a narrow circle of nuclear physicists, the question was just as acute: which is better - an atomic bomb or a hydrogen one, also known as thermonuclear one? The atomic bomb, which the Americans made in 1945, and we made in 1949, is built on the principle of releasing colossal energy by separating heavy nuclei of uranium or artificial plutonium. A thermonuclear bomb is built on a different principle: energy is released by the fusion of light isotopes of hydrogen, deuterium and tritium. Materials based on light elements do not have a critical mass, which was a great design difficulty in the atomic bomb. In addition, the fusion of deuterium and tritium releases 4.2 times more energy than the fission of nuclei of the same mass of uranium-235. In short, a hydrogen bomb is a much more powerful weapon than an atomic bomb.
In those years, the destructive power of the hydrogen bomb did not scare away any scientists. The world entered the era of the Cold War, McCarthyism was raging in the USA, and another wave of revelations arose in the USSR. Only Pyotr Kapitsa allowed himself demarches, who did not even appear at the ceremonial meeting at the Academy of Sciences on the occasion of Stalin’s 70th birthday. The issue of his expulsion from the ranks of the academy was discussed, but the situation was saved by the President of the Academy of Sciences Sergei Vavilov, who noted that the first to be expelled was the classic writer Sholokhov, who skimps on all meetings without exception.
As is known, scientists were helped by intelligence data in creating the atomic bomb. But our agents almost ruined the hydrogen bomb. The information obtained from the famous Klaus Fuchs led both Americans and Soviet physicists to a dead end. The group under the command of Zeldovich lost 6 years checking erroneous data. Intelligence also provided the opinion of the famous Niels Bohr about the unreality of the “superbomb”. But the USSR had its own ideas, the prospects of which were difficult and risky for Stalin and Beria, who were pushing for the atomic bomb with all their might. This circumstance must not be forgotten in fruitless and stupid disputes about who worked more on nuclear weapons - Soviet intelligence or Soviet science.
The work on the hydrogen bomb was the first intellectual race in human history. To create an atomic bomb, it was important, first of all, to solve engineering problems and carry out large-scale work in mines and factories. The hydrogen bomb led to the emergence of new scientific directions - physics of high-temperature plasma, physics of ultra-high energy densities, physics of anomalous pressures. For the first time I had to resort to mathematical modeling. Our scientists compensated for the lag behind the United States in the field of computers (von Neumann apparatuses were already in use overseas) with ingenious computational methods using primitive adding machines.
In short, it was the world's first battle of wits. And the USSR won this battle. An alternative design for a hydrogen bomb was invented by Andrei Sakharov, an ordinary employee of Zeldovich’s group. Back in 1949, he proposed the original idea of the so-called “puff paste”, where cheap uranium-238, which was considered waste in the production of weapons-grade uranium, was used as an effective nuclear material. But if this “waste” is bombarded by fusion neutrons, 10 times more energy-intensive than fission neutrons, then uranium-238 begins to fission and the cost of producing each kiloton is reduced many times over. The phenomenon of ionization compression of thermonuclear fuel, which became the basis of the first Soviet hydrogen bomb, is still called “saccharization.” Vitaly Ginzburg proposed lithium deuteride as a fuel.
Work on the atomic and hydrogen bombs proceeded in parallel. Even before the atomic bomb tests in 1949, Vavilov and Khariton informed Beria about the “sloika”. After the infamous directive of President Truman in early 1950, at a meeting of the Special Committee chaired by Beria, it was decided to speed up work on the Sakharov design with a TNT equivalent of 1 megaton and a test date of 1954.
On November 1, 1952, at Elugelub Atoll, the United States tested the Mike thermonuclear device with an energy release of 10 megatons, 500 times more powerful than the bomb dropped on Hiroshima. However, "Mike" was not a bomb - a gigantic structure the size of a two-story house. But the power of the explosion was amazing. The neutron flux was so great that it was possible to discover two new elements - einsteinium and fermium.
They threw all their efforts into the hydrogen bomb. The work was not slowed down by either the death of Stalin or the arrest of Beria. Finally, on August 12, 1953, the world's first hydrogen bomb was tested in Semipalatinsk. The environmental consequences were horrific. The first explosion during the nuclear tests in Semipalatinsk accounted for 82% of strontium-90 and 75% of cesium-137. But then no one thought about radioactive contamination, or about the environment in general.
The first hydrogen bomb caused the rapid development of Soviet cosmonautics. After the nuclear tests, the Korolev Design Bureau received the task of developing an intercontinental ballistic missile for this charge. This rocket, called the “seven”, launched the first artificial satellite of the Earth into space, and the first cosmonaut of the planet, Yuri Gagarin, launched on it.
On November 6, 1955, a hydrogen bomb dropped from a Tu-16 aircraft was tested for the first time. In the United States, the dropping of a hydrogen bomb took place only on May 21, 1956. But it turned out that Andrei Sakharov’s first bomb was also a dead end; it was never tested again. Even earlier - on March 1, 1954, near the Bikini Atoll, the United States detonated a charge of unheard-of power - 15 megatons. It was based on the idea of Teller and Ulam about the compression of the thermonuclear unit not by mechanical energy and neutron flux, but by the radiation of the first explosion, the so-called initiator. After the test, which resulted in casualties among the civilian population, Igor Tamm demanded that his colleagues abandon all previous ideas, even the national pride of the “sloyka” and find a fundamentally new path: “Everything that we have done so far is of no use to anyone. We are unemployed. I am confident that in a few months we will achieve our goal."
And already in the spring of 1954, Soviet physicists came up with the idea of an explosive initiator. The authorship of the idea belongs to Zeldovich and Sakharov. On November 22, 1955, a Tu-16 dropped a bomb with a design power of 3.6 megatons over the Semipalatinsk test site. During these tests there were deaths, the radius of destruction reached 350 km, and Semipalatinsk suffered.
There was a nuclear arms race ahead. But in 1955 it became clear that the USSR had achieved nuclear parity with the United States.
Atomic energy is released not only during the fission of atomic nuclei of heavy elements, but also during the combination (synthesis) of light nuclei into heavier ones.
For example, the nuclei of hydrogen atoms combine to form the nuclei of helium atoms, and more energy is released per unit weight of nuclear fuel than when uranium nuclei fission.
These nuclear fusion reactions, occurring at very high temperatures, measured in tens of millions of degrees, are called thermonuclear reactions. Weapons based on the use of energy instantly released as a result of a thermonuclear reaction are called thermonuclear weapons.
Thermonuclear weapons, which use hydrogen isotopes as a charge (nuclear explosive), are often called hydrogen weapons.
The fusion reaction between hydrogen isotopes - deuterium and tritium - is particularly successful.
Lithium deuterium (a compound of deuterium and lithium) can also be used as a charge for a hydrogen bomb.
Deuterium, or heavy hydrogen, occurs naturally in trace amounts in heavy water. Ordinary water contains about 0.02% heavy water as an impurity. To obtain 1 kg of deuterium, it is necessary to process at least 25 tons of water.
Tritium, or superheavy hydrogen, is practically never found in nature. It is obtained artificially, for example, by irradiating lithium with neutrons. Neutrons released in nuclear reactors can be used for this purpose.
Practically device hydrogen bomb can be imagined as follows: next to a hydrogen charge containing heavy and superheavy hydrogen (i.e., deuterium and tritium), there are two hemispheres of uranium or plutonium (atomic charge) located at a distance from each other.
To bring these hemispheres closer together, charges from a conventional explosive (TNT) are used. Exploding simultaneously, the TNT charges bring the hemispheres of the atomic charge closer together. At the moment of their connection, an explosion occurs, thereby creating conditions for a thermonuclear reaction, and consequently, an explosion of the hydrogen charge will occur. Thus, the reaction of a hydrogen bomb explosion goes through two phases: the first phase is the fission of uranium or plutonium, the second is the fusion phase, during which helium nuclei and free high-energy neutrons are formed. Currently, there are schemes for constructing a three-phase thermonuclear bomb.
In a three-phase bomb, the shell is made of uranium-238 (natural uranium). In this case, the reaction goes through three phases: the first fission phase (uranium or plutonium for detonation), the second is the thermonuclear reaction in lithium hydrite, and the third phase is the fission reaction of uranium-238. The fission of uranium nuclei is caused by neutrons, which are released in the form of a powerful stream during the fusion reaction.
Making a shell from uranium-238 makes it possible to increase the power of a bomb using the most accessible atomic raw materials. According to foreign press reports, bombs with a yield of 10-14 million tons or more have already been tested. It becomes obvious that this is not the limit. Further improvement of nuclear weapons is carried out both through the creation of especially high-power bombs and through the development of new designs that make it possible to reduce the weight and caliber of bombs. In particular, they are working on creating a bomb based entirely on fusion. There are, for example, reports in the foreign press about the possibility of using a new method of detonating thermonuclear bombs based on the use of shock waves of conventional explosives.
The energy released by the explosion of a hydrogen bomb can be thousands of times greater than the energy of an atomic bomb explosion. However, the radius of destruction cannot be as many times greater than the radius of destruction caused by the explosion of an atomic bomb.
The radius of action of a shock wave during an air explosion of a hydrogen bomb with a TNT equivalent of 10 million tons is approximately 8 times greater than the radius of action of a shock wave formed during the explosion of an atomic bomb with a TNT equivalent of 20,000 tons, while the power of the bomb is 500 times greater, tons . i.e. by the cubic root of 500. Accordingly, the destruction area increases by approximately 64 times, i.e., in proportion to the cubic root of the coefficient of increase in the power of the bomb squared.
According to foreign authors, with a nuclear explosion with a capacity of 20 million tons, the area of complete destruction of ordinary ground-based structures, according to American experts, can reach 200 km 2, the zone of significant destruction - 500 km 2 and partial - up to 2580 km 2.
This means, foreign experts conclude, that the explosion of one bomb of similar power is enough to destroy a modern large city. As you know, the occupied area of Paris is 104 km2, London - 300 km2, Chicago - 550 km2, Berlin - 880 km2.
The scale of damage and destruction from a nuclear explosion with a capacity of 20 million tons can be presented schematically in the following form:
The area of lethal doses of initial radiation within a radius of up to 8 km (over an area of up to 200 km 2);
Area of damage by light radiation (burns)] within a radius of up to 32 km (over an area of about 3000 km 2).
Damage to residential buildings (glasses broken, plaster crumbling, etc.) can be observed even at a distance of up to 120 km from the explosion site.
The given data from open foreign sources are indicative; they were obtained during testing of lower-yield nuclear weapons and through calculations. Deviations from these data in one direction or another will depend on various factors, and primarily on the terrain, the nature of the development, meteorological conditions, vegetation cover, etc.
The damage radius can be changed to a large extent by artificially creating certain conditions that reduce the effect of the damaging factors of the explosion. For example, it is possible to reduce the damaging effect of light radiation, reduce the area where burns can occur on people and objects can ignite, by creating a smoke screen.
Experiments carried out in the USA to create smoke screens for nuclear explosions in 1954-1955. showed that with a curtain density (oil mists) obtained with a consumption of 440-620 liters of oil per 1 km 2, the impact of light radiation from a nuclear explosion, depending on the distance to the epicenter, can be weakened by 65-90%.
Other smokes also weaken the damaging effects of light radiation, which are not only not inferior, but in some cases superior to oil fogs. In particular, industrial smoke, which reduces atmospheric visibility, can reduce the effects of light radiation to the same extent as oil mists.
It is much possible to reduce the damaging effect of nuclear explosions through the dispersed construction of settlements, the creation of forest areas, etc.
Of particular note is the sharp decrease in the radius of destruction of people depending on the use of certain protective equipment. It is known, for example, that even at a relatively small distance from the epicenter of the explosion, a reliable shelter from the effects of light radiation and penetrating radiation is a shelter with a layer of earthen covering 1.6 m thick or a layer of concrete 1 m thick.
A light-type shelter reduces the radius of the affected area by six times compared to an open location, and the affected area is reduced by tens of times. When using covered slots, the radius of possible damage is reduced by 2 times.
Consequently, with the maximum use of all available methods and means of protection, it is possible to achieve a significant reduction in the impact of the damaging factors of nuclear weapons and thereby reduce human and material losses during their use.
Speaking about the scale of destruction that can be caused by explosions of high-power nuclear weapons, it is necessary to keep in mind that damage will be caused not only by the action of a shock wave, light radiation and penetrating radiation, but also by the action of radioactive substances falling along the path of movement of the cloud formed during the explosion , which includes not only gaseous explosion products, but also solid particles of various sizes, both in weight and size. Especially large amounts of radioactive dust are generated during ground explosions.
The height of the cloud and its size largely depend on the power of the explosion. According to foreign press reports, during tests of nuclear charges with a capacity of several million tons of TNT, which were carried out by the United States in the Pacific Ocean in 1952-1954, the top of the cloud reached a height of 30-40 km.
In the first minutes after the explosion, the cloud has the shape of a ball and over time it stretches in the direction of the wind, reaching a huge size (about 60-70 km).
About an hour after the explosion of a bomb with a TNT equivalent of 20 thousand tons, the volume of the cloud reaches 300 km 3, and with the explosion of a bomb of 20 million tons, the volume can reach 10 thousand km 3.
Moving in the direction of the flow of air masses, an atomic cloud can occupy a strip several tens of kilometers long.
From the cloud, as it moves, after rising to the upper layers of the rarefied atmosphere, within a few minutes radioactive dust begins to fall to the ground, contaminating an area of several thousand square kilometers along the way.
At first, the heaviest dust particles fall out, which have time to settle within a few hours. The bulk of coarse dust falls in the first 6-8 hours after the explosion.
About 50% of the particles (the largest) of radioactive dust fall out during the first 8 hours after the explosion. This loss is often called local in contrast to general, widespread.
Smaller dust particles remain in the air at various altitudes and fall to the ground for about two weeks after the explosion. During this time, the cloud can circle the globe several times, capturing a wide strip parallel to the latitude at which the explosion took place.
Small particles (up to 1 micron) remain in the upper layers of the atmosphere, distributed more evenly around the globe, and fall out over the next number of years. According to scientists, the fallout of fine radioactive dust has continued everywhere for about ten years.
The greatest danger to the population is radioactive dust falling in the first hours after the explosion, since the level of radioactive contamination is so high that it can cause fatal injuries to people and animals who find themselves in the area along the path of the radioactive cloud.
The size of the area and the degree of contamination of the area as a result of the fall of radioactive dust largely depend on meteorological conditions, terrain, height of the explosion, the size of the bomb charge, the nature of the soil, etc. The most important factor determining the size of the contamination area and its configuration is the direction and the strength of the winds prevailing in the area of the explosion at various altitudes.
To determine the possible direction of cloud movement, it is necessary to know in which direction and at what speed the wind is blowing at various altitudes, starting from an altitude of about 1 km and ending at 25-30 km. To do this, the weather service must conduct continuous observations and measurements of wind using radiosondes at various altitudes; Based on the data obtained, determine in which direction the radioactive cloud is most likely to move.
During the explosion of a hydrogen bomb carried out by the United States in 1954 in the central Pacific Ocean (on Bikini Atoll), the contaminated area of the territory had the shape of an elongated ellipse, which extended 350 km downwind and 30 km against the wind. The greatest width of the strip was about 65 km. The total area of dangerous contamination reached about 8 thousand km 2.
As is known, as a result of this explosion, the Japanese fishing vessel Fukuryumaru, which was at that time at a distance of about 145 km, was contaminated with radioactive dust. The 23 fishermen on board the ship were injured, one of them fatally.
The radioactive dust that fell after the explosion on March 1, 1954 also exposed 29 American employees and 239 residents of the Marshall Islands, all of whom were injured at a distance of more than 300 km from the explosion site. Other ships located in the Pacific Ocean at a distance of up to 1,500 km from Bikini, and some fish near the Japanese coast also turned out to be infected.
The contamination of the atmosphere with explosion products was indicated by the rains that fell in May on the Pacific coast and Japan, in which greatly increased radioactivity was detected. The areas where radioactive fallout occurred during May 1954 cover about a third of Japan's entire territory.
The above data on the scale of damage that can be inflicted on the population by the explosion of large-caliber atomic bombs show that high-power nuclear charges (millions of tons of TNT) can be considered radiological weapons, i.e. weapons that damage more with the radioactive products of the explosion than with the impact wave, light radiation and penetrating radiation acting at the moment of explosion.
Therefore, in the course of preparing populated areas and national economic facilities for civil defense, it is necessary to provide everywhere for measures to protect the population, animals, food, fodder and water from contamination by products of the explosion of nuclear charges, which may fall along the path of the radioactive cloud.
It should be borne in mind that as a result of the fallout of radioactive substances, not only the surface of the soil and objects will be contaminated, but also the air, vegetation, water in open reservoirs, etc. The air will be contaminated both during the period of deposition of radioactive particles and in the future, especially along roads during traffic or in windy weather, when settled dust particles will again rise into the air.
Consequently, unprotected people and animals may be affected by radioactive dust that enters the respiratory system along with the air.
Food and water contaminated with radioactive dust, which, if entering the body, can cause serious illness, sometimes fatal, will also be dangerous. Thus, in the area where radioactive substances formed during a nuclear explosion fall out, people will be exposed not only to external radiation, but also when contaminated food, water or air enters the body. When organizing protection against damage from the products of a nuclear explosion, it should be taken into account that the degree of contamination along the cloud's path decreases with distance from the explosion site.
Therefore, the danger to which the population located in the area of the contamination zone is exposed is not the same at different distances from the explosion site. The most dangerous areas will be areas close to the explosion site and areas located along the axis of cloud movement (the middle part of the strip along the cloud movement track).
The unevenness of radioactive contamination along the path of cloud movement is to a certain extent natural. This circumstance must be taken into account when organizing and conducting measures for radiation protection of the population.
It is also necessary to take into account that some time passes from the moment of explosion to the moment radioactive substances fall out of the cloud. This time increases the further you are from the explosion site, and can amount to several hours. The population of areas remote from the explosion site will have sufficient time to take appropriate protective measures.
In particular, provided that warning means are prepared in a timely manner and the relevant civil defense units work efficiently, the population can be notified of the danger in about 2-3 hours.
During this time, with advance preparation of the population and high level of organization, a number of measures can be carried out to provide fairly reliable protection against radioactive damage to people and animals. The choice of certain measures and methods of protection will be determined by the specific conditions of the current situation. However, general principles must be defined and civil defense plans developed in advance according to this.
It can be considered that, under certain conditions, it would be most rational to take protective measures first and foremost on the spot, using all means and. methods that protect both from the entry of radioactive substances into the body and from external radiation.
As is known, the most effective means of protection from external radiation are shelters (adapted to meet the requirements of nuclear protection, as well as buildings with massive walls, built of dense materials (brick, cement, reinforced concrete, etc.), including basements, dugouts , cellars, covered spaces and ordinary residential buildings.
When assessing the protective properties of buildings and structures, you can be guided by the following indicative data: a wooden house weakens the effect of radioactive radiation depending on the thickness of the walls by 4-10 times, a stone house - by 10-50 times, cellars and basements in wooden houses - by 50-100 times, a gap with an overlap of a layer of earth of 60-90 cm - 200-300 times.
Consequently, civil defense plans should provide for the use, if necessary, first of all of structures with more powerful protective means; upon receiving a signal about the danger of destruction, the population must immediately take refuge in these premises and remain there until further actions are announced.
The length of time people spend in the premises intended for shelter will depend mainly on the extent to which the area where the settlement is located is contaminated, and the rate at which the radiation level decreases over time.
So, for example, in populated areas located at a considerable distance from the explosion site, where the total radiation doses that unprotected people will receive can become safe within a short time, it is advisable for the population to wait out this time in shelters.
In areas of severe radioactive contamination, where the total dose that unprotected people can receive will be high and its reduction will be prolonged under these conditions, long-term stay of people in shelters will become difficult. Therefore, the most rational thing to do in such areas is to first shelter the population in place and then evacuate it to uncontaminated areas. The beginning of the evacuation and its duration will depend on local conditions: the level of radioactive contamination, the availability of vehicles, communication routes, time of year, remoteness of the places where evacuees are located, etc.
Thus, the territory of radioactive contamination according to the trace of the radioactive cloud can be divided conditionally into two zones with different principles for protecting the population.
The first zone includes the territory where radiation levels remain high 5-6 days after the explosion and decrease slowly (by about 10-20% daily). Evacuation of the population from such areas can begin only after the radiation level has decreased to such levels that during the collection and movement in the contaminated area people will not receive a total dose of more than 50 rubles.
The second zone includes areas in which radiation levels decrease during the first 3-5 days after the explosion to 0.1 roentgen/hour.
Evacuation of the population from this zone is not advisable, since this time can be waited out in shelters.
Successful implementation of measures to protect the population in all cases is unthinkable without thorough radiation reconnaissance and monitoring and constant monitoring of radiation levels.
Speaking about protecting the population from radioactive damage following the movement of a cloud formed during a nuclear explosion, it should be remembered that it is possible to avoid damage or achieve its reduction only with a clear organization of a set of measures, which include:
- organization of a warning system that provides timely warning to the population about the most likely direction of movement of the radioactive cloud and the danger of damage. For these purposes, all available means of communication must be used - telephone, radio stations, telegraph, radio broadcast, etc.;
- training civil defense units to conduct reconnaissance both in cities and in rural areas;
- sheltering people in shelters or other premises that protect from radioactive radiation (basements, cellars, crevices, etc.);
- carrying out the evacuation of the population and animals from the area of persistent contamination with radioactive dust;
- preparing units and institutions of the civil defense medical service for actions to provide assistance to those affected, mainly treatment, sanitization, examination of water and food products for contamination with radioactive substances;
- carrying out in advance measures to protect food products in warehouses, retail chains, public catering establishments, as well as water supplies from contamination by radioactive dust (sealing warehouses, preparing containers, improvised materials for covering products, preparing means for decontaminating food and containers, equipment dosimetric instruments);
- carrying out measures to protect animals and providing assistance to animals in case of defeat.
To ensure reliable protection of animals, it is necessary to provide for keeping them on collective farms and state farms, if possible in small groups in teams, farms or settlements with shelter areas.
It is also necessary to provide for the creation of additional reservoirs or wells, which can become backup sources of water supply in the event of contamination of water from permanent sources.
Warehouses in which fodder is stored, as well as livestock buildings, which should be sealed whenever possible, become important.
To protect valuable breeding animals, it is necessary to have personal protective equipment, which can be made from available materials on site (eye bands, bags, blankets, etc.), as well as gas masks (if available).
To carry out decontamination of premises and veterinary treatment of animals, it is necessary to take into account in advance the disinfection installations, sprayers, sprinklers, liquid spreaders and other mechanisms and containers available on the farm, with the help of which disinfection and veterinary treatment work can be carried out;
Organization and preparation of formations and institutions to carry out work on the decontamination of structures, terrain, vehicles, clothing, equipment and other civil defense property, for which measures are taken in advance to adapt municipal equipment, agricultural machines, mechanisms and devices for these purposes. Depending on the availability of equipment, appropriate formations must be created and trained - detachments, teams, groups, units, etc.
How Soviet physicists made the hydrogen bomb, what pros and cons this terrible weapon carried, read in the “History of Science” section.
After World War II, it was still impossible to talk about the actual onset of peace - two major world powers entered an arms race. One of the facets of this conflict was the confrontation between the USSR and the USA in the creation of nuclear weapons. In 1945, the United States, the first to enter the race behind the scenes, dropped nuclear bombs on the notorious cities of Hiroshima and Nagasaki. The Soviet Union also carried out work on creating nuclear weapons, and in 1949 they tested the first atomic bomb, the working substance of which was plutonium. Even during its development, Soviet intelligence found out that the United States had switched to developing a more powerful bomb. This prompted the USSR to start producing thermonuclear weapons.
The intelligence officers were unable to find out what results the Americans achieved, and the attempts of Soviet nuclear scientists were not successful. Therefore, it was decided to create a bomb, the explosion of which would occur due to the synthesis of light nuclei, and not the fission of heavy ones, as in an atomic bomb. In the spring of 1950, work began on creating a bomb, which later received the name RDS-6s. Among its developers was the future Nobel Peace Prize laureate Andrei Sakharov, who proposed the idea of designing a charge back in 1948, but later opposed nuclear tests.
Andrey Sakharov
Vladimir Fedorenko/Wikimedia Commons
Sakharov proposed covering a plutonium core with several layers of light and heavy elements, namely uranium and deuterium, an isotope of hydrogen. Subsequently, however, it was proposed to replace deuterium with lithium deuteride - this significantly simplified the design of the charge and its operation. An additional advantage was that lithium, after bombardment with neutrons, produces another isotope of hydrogen - tritium. When tritium reacts with deuterium, it releases much more energy. In addition, lithium also slows down neutrons better. This structure of the bomb gave it the nickname “Sloika”.
A certain challenge was that the thickness of each layer and their final quantity were also very important for a successful test. According to calculations, from 15% to 20% of the energy released during the explosion came from thermonuclear reactions, and another 75-80% from the fission of uranium-235, uranium-238 and plutonium-239 nuclei. It was also assumed that the charge power would be from 200 to 400 kilotons; the practical result was at the upper limit of the forecasts.
On Day X, August 12, 1953, the first Soviet hydrogen bomb was tested in action. The Semipalatinsk test site where the explosion occurred was located in the East Kazakhstan region. The test of the RDS-6s was preceded by an attempt in 1949 (at that time a ground explosion of a bomb with a yield of 22.4 kilotons was carried out at the test site). Despite the isolated location of the test site, the population of the region experienced first-hand the beauty of nuclear testing. People who lived relatively close to the test site for decades, until the closure of the test site in 1991, were exposed to radiation, and areas many kilometers from the test site were contaminated with nuclear decay products.
The first Soviet hydrogen bomb RDS-6s
Wikimedia Commons
A week before the RDS-6s test, according to eyewitnesses, the military gave money and food to the families living near the test site, but there was no evacuation or information about the upcoming events. The radioactive soil was removed from the test site itself, and nearby structures and observation posts were restored. It was decided to detonate the hydrogen bomb on the surface of the earth, despite the fact that the configuration made it possible to drop it from an airplane.
Previous tests of atomic charges were strikingly different from what nuclear scientists recorded after the Sakharov puff test. The energy output of the bomb, which critics call not a thermonuclear bomb but a thermonuclear-enhanced atomic bomb, was 20 times greater than that of previous charges. This was noticeable to the naked eye wearing sunglasses: only dust remained from the surviving and restored buildings after the hydrogen bomb test.
The hydrogen or thermonuclear bomb became the cornerstone of the arms race between the USA and the USSR. The two superpowers argued for several years about who would become the first owner of a new type of destructive weapon.
Thermonuclear weapon project
At the beginning of the Cold War, testing a hydrogen bomb was the most important argument for the leadership of the USSR in the fight against the United States. Moscow wanted to achieve nuclear parity with Washington and invested huge amounts of money in the arms race. However, work on creating a hydrogen bomb began not thanks to generous funding, but because of reports from secret agents in America. In 1945, the Kremlin learned that the United States was preparing to create a new weapon. It was a superbomb, the project of which was called Super.
The source of valuable information was Klaus Fuchs, an employee of the Los Alamos National Laboratory in the USA. He provided the Soviet Union with specific information regarding the secret American development of a superbomb. By 1950, the Super project was thrown into the trash, as it became clear to Western scientists that such a new weapon scheme could not be implemented. The director of this program was Edward Teller.
In 1946, Klaus Fuchs and John developed the ideas of the Super project and patented their own system. The principle of radioactive implosion was fundamentally new in it. In the USSR, this scheme began to be considered a little later - in 1948. In general, we can say that at the starting stage it was completely based on American information received by intelligence. But by continuing research based on these materials, Soviet scientists were noticeably ahead of their Western colleagues, which allowed the USSR to obtain first the first, and then the most powerful thermonuclear bomb.
On December 17, 1945, at a meeting of a special committee created under the Council of People's Commissars of the USSR, nuclear physicists Yakov Zeldovich, Isaac Pomeranchuk and Julius Hartion made a report “Use of nuclear energy of light elements.” This paper examined the possibility of using a deuterium bomb. This speech marked the beginning of the Soviet nuclear program.
In 1946, theoretical research was carried out at the Institute of Chemical Physics. The first results of this work were discussed at one of the meetings of the Scientific and Technical Council in the First Main Directorate. Two years later, Lavrentiy Beria instructed Kurchatov and Khariton to analyze materials about the von Neumann system, which were delivered to the Soviet Union thanks to secret agents in the West. Data from these documents gave additional impetus to the research that led to the birth of the RDS-6 project.
"Evie Mike" and "Castle Bravo"
On November 1, 1952, the Americans tested the world's first thermonuclear device. It was not yet a bomb, but already its most important component. The explosion occurred on Enivotek Atoll, in the Pacific Ocean. and Stanislav Ulam (each of them actually the creator of the hydrogen bomb) had recently developed a two-stage design, which the Americans tested. The device could not be used as a weapon, as it was produced using deuterium. In addition, it was distinguished by its enormous weight and dimensions. Such a projectile simply could not be dropped from an airplane.
The first hydrogen bomb was tested by Soviet scientists. After the United States learned about the successful use of the RDS-6s, it became clear that it was necessary to close the gap with the Russians in the arms race as quickly as possible. The American test took place on March 1, 1954. The Bikini Atoll in the Marshall Islands was chosen as the test site. The Pacific archipelagos were not chosen by chance. There was almost no population here (and the few people who lived on the nearby islands were evicted on the eve of the experiment).
The Americans' most destructive hydrogen bomb explosion became known as Castle Bravo. The charge power turned out to be 2.5 times higher than expected. The explosion led to radiation contamination of a large area (many islands and the Pacific Ocean), which led to a scandal and a revision of the nuclear program.
Development of RDS-6s
The project of the first Soviet thermonuclear bomb was called RDS-6s. The plan was written by the outstanding physicist Andrei Sakharov. In 1950, the Council of Ministers of the USSR decided to concentrate work on the creation of new weapons in KB-11. According to this decision, a group of scientists led by Igor Tamm went to the closed Arzamas-16.
The Semipalatinsk test site was prepared especially for this grandiose project. Before the hydrogen bomb test began, numerous measuring, filming and recording instruments were installed there. In addition, on behalf of scientists, almost two thousand indicators appeared there. The area affected by the hydrogen bomb test included 190 structures.
The Semipalatinsk experiment was unique not only because of the new type of weapon. Unique intakes designed for chemical and radioactive samples were used. Only a powerful shock wave could open them. Recording and filming instruments were installed in specially prepared fortified structures on the surface and in underground bunkers.
Alarm Clock
Back in 1946, Edward Teller, who worked in the USA, developed a prototype of the RDS-6s. It's called Alarm Clock. The project for this device was originally proposed as an alternative to the Super. In April 1947, a series of experiments began at the Los Alamos laboratory designed to study the nature of thermonuclear principles.
Scientists expected the greatest energy release from Alarm Clock. In the fall, Teller decided to use lithium deuteride as fuel for the device. The researchers had not yet used this substance, but expected that it would improve efficiency. Interestingly, Teller already noted in his memos the dependence of the nuclear program on the further development of computers. This technique was necessary for scientists to make more accurate and complex calculations.
Alarm Clock and RDS-6s had much in common, but they also differed in many ways. The American version was not as practical as the Soviet one due to its size. It inherited its large size from the Super project. In the end, the Americans had to abandon this development. The last studies took place in 1954, after which it became clear that the project was unprofitable.
Explosion of the first thermonuclear bomb
The first test of a hydrogen bomb in human history occurred on August 12, 1953. In the morning, a bright flash appeared on the horizon, which was blinding even through protective glasses. The RDS-6s explosion turned out to be 20 times more powerful than an atomic bomb. The experiment was considered successful. Scientists were able to achieve an important technological breakthrough. For the first time, lithium hydride was used as a fuel. Within a radius of 4 kilometers from the epicenter of the explosion, the wave destroyed all buildings.
Subsequent tests of the hydrogen bomb in the USSR were based on the experience gained using the RDS-6s. This destructive weapon was not only the most powerful. An important advantage of the bomb was its compactness. The projectile was placed in a Tu-16 bomber. Success allowed Soviet scientists to get ahead of the Americans. In the United States at that time there was a thermonuclear device the size of a house. It was not transportable.
When Moscow announced that the USSR's hydrogen bomb was ready, Washington disputed this information. The main argument of the Americans was the fact that the thermonuclear bomb should be made according to the Teller-Ulam scheme. It was based on the principle of radiation implosion. This project will be implemented in the USSR two years later, in 1955.
Physicist Andrei Sakharov made the greatest contribution to the creation of RDS-6s. The hydrogen bomb was his brainchild - it was he who proposed the revolutionary technical solutions that made it possible to successfully complete tests at the Semipalatinsk test site. Young Sakharov immediately became an academician at the USSR Academy of Sciences, a Hero of Socialist Labor and a laureate of other scientists: Yuli Khariton, Kirill Shchelkin, Yakov Zeldovich, Nikolai Dukhov, etc. In 1953, the test of a hydrogen bomb showed that Soviet science could to overcome what until recently seemed fiction and fantasy. Therefore, immediately after the successful explosion of the RDS-6s, the development of even more powerful projectiles began.
RDS-37
On November 20, 1955, the next tests of a hydrogen bomb took place in the USSR. This time it was two-stage and corresponded to the Teller-Ulam scheme. The RDS-37 bomb was about to be dropped from an airplane. However, when it took off, it became clear that the tests would have to be carried out in an emergency situation. Contrary to weather forecasters, the weather deteriorated noticeably, causing dense clouds to cover the training ground.
For the first time, experts were forced to land a plane with a thermonuclear bomb on board. For some time there was a discussion at the Central Command Post about what to do next. A proposal to drop a bomb in the mountains nearby was considered, but this option was rejected as too risky. Meanwhile, the plane continued to circle near the test site, running out of fuel.
Zeldovich and Sakharov received the final word. A hydrogen bomb that exploded outside the test site would have led to disaster. The scientists understood the full extent of the risk and their own responsibility, and yet they gave written confirmation that the plane would be safe to land. Finally, the commander of the Tu-16 crew, Fyodor Golovashko, received the command to land. The landing was very smooth. The pilots showed all their skills and did not panic in a critical situation. The maneuver was perfect. The Central Command Post breathed a sigh of relief.
The creator of the hydrogen bomb, Sakharov, and his team survived the tests. The second attempt was scheduled for November 22. On this day everything went without any emergency situations. The bomb was dropped from a height of 12 kilometers. While the shell was falling, the plane managed to move to a safe distance from the epicenter of the explosion. A few minutes later, the nuclear mushroom reached a height of 14 kilometers, and its diameter was 30 kilometers.
The explosion was not without tragic incidents. The shock wave shattered glass at a distance of 200 kilometers, causing several injuries. A girl who lived in a neighboring village also died when the ceiling collapsed on her. Another victim was a soldier who was in a special holding area. The soldier fell asleep in the dugout and died of suffocation before his comrades could pull him out.
Development of the Tsar Bomba
In 1954, the country's best nuclear physicists, under the leadership, began developing the most powerful thermonuclear bomb in the history of mankind. Andrei Sakharov, Viktor Adamsky, Yuri Babaev, Yuri Smirnov, Yuri Trutnev, etc. also took part in this project. Due to its power and size, the bomb became known as the “Tsar Bomba”. Project participants later recalled that this phrase appeared after Khrushchev’s famous statement about “Kuzka’s mother” at the UN. Officially, the project was called AN602.
Over seven years of development, the bomb went through several reincarnations. At first, scientists planned to use components from uranium and the Jekyll-Hyde reaction, but later this idea had to be abandoned due to the danger of radioactive contamination.
Test on Novaya Zemlya
For some time, the Tsar Bomba project was frozen, as Khrushchev was going to the United States, and there was a short pause in the Cold War. In 1961, the conflict between the countries flared up again and Moscow again remembered thermonuclear weapons. Khrushchev announced the upcoming tests in October 1961 during the XXII Congress of the CPSU.
On the 30th, a Tu-95B with a bomb on board took off from Olenya and headed for Novaya Zemlya. The plane took two hours to reach its destination. Another Soviet hydrogen bomb was dropped at an altitude of 10.5 thousand meters above the Sukhoi Nos nuclear test site. The shell exploded while still in the air. A fireball appeared, which reached a diameter of three kilometers and almost touched the ground. According to scientists' calculations, the seismic wave from the explosion crossed the planet three times. The impact was felt a thousand kilometers away, and everything living at a distance of a hundred kilometers could receive third-degree burns (this did not happen, since the area was uninhabited).
At that time, the most powerful US thermonuclear bomb was four times less powerful than the Tsar Bomba. The Soviet leadership was pleased with the result of the experiment. Moscow got what it wanted from the next hydrogen bomb. The test demonstrated that the USSR had weapons much more powerful than the United States. Subsequently, the destructive record of the “Tsar Bomba” was never broken. The most powerful hydrogen bomb explosion was a major milestone in the history of science and the Cold War.
Thermonuclear weapons of other countries
British development of the hydrogen bomb began in 1954. The project manager was William Penney, who had previously been a participant in the Manhattan Project in the USA. The British had crumbs of information about the structure of thermonuclear weapons. American allies did not share this information. In Washington, they referred to the atomic energy law passed in 1946. The only exception for the British was permission to observe the tests. They also used aircraft to collect samples left behind by American shell explosions.
At first, London decided to limit itself to creating a very powerful atomic bomb. Thus began the Orange Messenger trials. During them, the most powerful non-thermonuclear bomb in human history was dropped. Its disadvantage was its excessive cost. On November 8, 1957, a hydrogen bomb was tested. The history of the creation of the British two-stage device is an example of successful progress in conditions of lagging behind two superpowers that were arguing among themselves.
The hydrogen bomb appeared in China in 1967, in France in 1968. Thus, today there are five states in the club of countries possessing thermonuclear weapons. Information about the hydrogen bomb in North Korea remains controversial. The head of the DPRK stated that his scientists were able to develop such a projectile. During the tests, seismologists from different countries recorded seismic activity caused by a nuclear explosion. But there is still no concrete information about the hydrogen bomb in the DPRK.
The hydrogen bomb (Hydrogen Bomb, HB) is a weapon of mass destruction with incredible destructive power (its power is estimated at megatons of TNT). The principle of operation of the bomb and its structure are based on the use of the energy of thermonuclear fusion of hydrogen nuclei. The processes occurring during the explosion are similar to those occurring on stars (including the Sun). The first test of a VB suitable for long-distance transportation (designed by A.D. Sakharov) was carried out in the Soviet Union at a test site near Semipalatinsk.
Thermonuclear reaction
The sun contains huge reserves of hydrogen, which is under constant influence of ultra-high pressure and temperature (about 15 million degrees Kelvin). At such an extreme plasma density and temperature, the nuclei of hydrogen atoms randomly collide with each other. The result of collisions is the fusion of nuclei, and as a consequence, the formation of nuclei of a heavier element - helium. Reactions of this type are called thermonuclear fusion; they are characterized by the release of colossal amounts of energy.
The laws of physics explain the energy release during a thermonuclear reaction as follows: part of the mass of light nuclei involved in the formation of heavier elements remains unused and is converted into pure energy in colossal quantities. That is why our celestial body loses approximately 4 million tons of matter per second, while releasing a continuous flow of energy into outer space.
Isotopes of hydrogen
The simplest of all existing atoms is the hydrogen atom. It consists of only one proton, forming the nucleus, and a single electron orbiting around it. As a result of scientific studies of water (H2O), it was found that it contains so-called “heavy” water in small quantities. It contains “heavy” isotopes of hydrogen (2H or deuterium), the nuclei of which, in addition to one proton, also contain one neutron (a particle close in mass to a proton, but devoid of charge).
Science also knows tritium, the third isotope of hydrogen, the nucleus of which contains 1 proton and 2 neutrons. Tritium is characterized by instability and constant spontaneous decay with the release of energy (radiation), resulting in the formation of a helium isotope. Traces of tritium are found in the upper layers of the Earth's atmosphere: it is there, under the influence of cosmic rays, that the molecules of gases that form air undergo similar changes. Tritium can also be produced in a nuclear reactor by irradiating the lithium-6 isotope with a powerful neutron flux.
Development and first tests of the hydrogen bomb
As a result of a thorough theoretical analysis, experts from the USSR and the USA came to the conclusion that a mixture of deuterium and tritium makes it easiest to launch a thermonuclear fusion reaction. Armed with this knowledge, scientists from the United States in the 50s of the last century began to create a hydrogen bomb. And already in the spring of 1951, a test test was carried out at the Enewetak test site (an atoll in the Pacific Ocean), but then only partial thermonuclear fusion was achieved.
A little more than a year passed, and in November 1952, the second test of a hydrogen bomb with a yield of about 10 Mt of TNT was carried out. However, that explosion can hardly be called an explosion of a thermonuclear bomb in the modern sense: in fact, the device was a large container (the size of a three-story building) filled with liquid deuterium.
Russia also took up the task of improving atomic weapons, and the first hydrogen bomb of the A.D. project. Sakharov was tested at the Semipalatinsk test site on August 12, 1953. RDS-6 (this type of weapon of mass destruction was nicknamed Sakharov’s “puff”, since its design involved the sequential placement of layers of deuterium surrounding the initiator charge) had a power of 10 Mt. However, unlike the American “three-story house,” the Soviet bomb was compact, and it could be quickly delivered to the drop site on enemy territory on a strategic bomber.
Accepting the challenge, the United States in March 1954 exploded a more powerful aerial bomb (15 Mt) at a test site on Bikini Atoll (Pacific Ocean). The test caused the release of a large amount of radioactive substances into the atmosphere, some of which fell in precipitation hundreds of kilometers from the epicenter of the explosion. The Japanese ship "Lucky Dragon" and instruments installed on Rogelap Island recorded a sharp increase in radiation.
Since the processes that occur during the detonation of a hydrogen bomb produce stable, harmless helium, it was expected that radioactive emissions should not exceed the level of contamination from an atomic fusion detonator. But calculations and measurements of actual radioactive fallout varied greatly, both in quantity and composition. Therefore, the US leadership decided to temporarily suspend the design of this weapon until its impact on the environment and humans is fully studied.
Video: tests in the USSR
Tsar Bomba - thermonuclear bomb of the USSR
The USSR marked a milestone in the chain of hydrogen bomb production when on October 30, 1961, a test of the 50-megaton (largest in history) “Tsar Bomb” was carried out on Novaya Zemlya - the result of many years of work by A.D.’s research group. Sakharov. The explosion occurred at an altitude of 4 kilometers, and the shock wave was recorded three times by instruments around the globe. Despite the fact that the test did not reveal any failures, the bomb never entered service. But the very fact that the Soviets possessed such weapons made an indelible impression on the whole world, and the United States stopped accumulating the tonnage of its nuclear arsenal. Russia, in turn, decided to abandon the introduction of warheads with hydrogen charges into combat duty.
A hydrogen bomb is a complex technical device, the explosion of which requires the sequential occurrence of a number of processes.
First, the initiator charge located inside the shell of the VB (miniature atomic bomb) detonates, resulting in a powerful release of neutrons and the creation of the high temperature required to begin thermonuclear fusion in the main charge. Massive neutron bombardment of the lithium deuteride insert (obtained by combining deuterium with the lithium-6 isotope) begins.
Under the influence of neutrons, lithium-6 splits into tritium and helium. The atomic fuse in this case becomes a source of materials necessary for thermonuclear fusion to occur in the detonated bomb itself.
A mixture of tritium and deuterium triggers a thermonuclear reaction, causing the temperature inside the bomb to rapidly increase, and more and more hydrogen is involved in the process.
The principle of operation of a hydrogen bomb implies the ultra-fast occurrence of these processes (the charge device and the layout of the main elements contribute to this), which to the observer appear instantaneous.
Superbomb: fission, fusion, fission
The sequence of processes described above ends after the start of the reaction of deuterium with tritium. Next, it was decided to use nuclear fission rather than fusion of heavier ones. After the fusion of tritium and deuterium nuclei, free helium and fast neutrons are released, the energy of which is sufficient to initiate the fission of uranium-238 nuclei. Fast neutrons are capable of splitting atoms from the uranium shell of a superbomb. The fission of a ton of uranium generates energy of about 18 Mt. In this case, energy is spent not only on creating a blast wave and releasing a colossal amount of heat. Each uranium atom decays into two radioactive “fragments.” A whole “bouquet” of various chemical elements (up to 36) and about two hundred radioactive isotopes is formed. It is for this reason that numerous radioactive fallouts are formed, recorded hundreds of kilometers from the epicenter of the explosion.
After the fall of the Iron Curtain, it became known that the USSR was planning to develop a “Tsar Bomb” with a capacity of 100 Mt. Due to the fact that at that time there was no aircraft capable of carrying such a massive charge, the idea was abandoned in favor of a 50 Mt bomb.
Consequences of a hydrogen bomb explosion
Shock wave
The explosion of a hydrogen bomb entails large-scale destruction and consequences, and the primary (obvious, direct) impact is threefold. The most obvious of all direct impacts is a shock wave of ultra-high intensity. Its destructive ability decreases with distance from the epicenter of the explosion, and also depends on the power of the bomb itself and the height at which the charge detonated.
Thermal effect
The effect of the thermal impact of an explosion depends on the same factors as the power of the shock wave. But one more thing is added to them - the degree of transparency of air masses. Fog or even slight cloudiness sharply reduces the radius of damage over which a thermal flash can cause serious burns and loss of vision. The explosion of a hydrogen bomb (more than 20 Mt) generates an incredible amount of thermal energy, sufficient to melt concrete at a distance of 5 km, evaporate almost all the water from a small lake at a distance of 10 km, destroy enemy personnel, equipment and buildings at the same distance . In the center, a funnel with a diameter of 1-2 km and a depth of up to 50 m is formed, covered with a thick layer of glassy mass (several meters of rocks with a high sand content melt almost instantly, turning into glass).
According to calculations based on real-life tests, people have a 50% chance of surviving if they:
- They are located in a reinforced concrete shelter (underground) 8 km from the epicenter of the explosion (EV);
- They are located in residential buildings at a distance of 15 km from the EV;
- They will find themselves in an open area at a distance of more than 20 km from the EV with poor visibility (for a “clean” atmosphere, the minimum distance in this case will be 25 km).
With distance from EVs, the probability of surviving in people who find themselves in open areas increases sharply. So, at a distance of 32 km it will be 90-95%. A radius of 40-45 km is the limit for the primary impact of an explosion.
Fireball
Another obvious impact from a hydrogen bomb explosion is self-sustaining firestorms (hurricanes), formed as a result of colossal masses of flammable material being drawn into the fireball. But, despite this, the most dangerous consequence of the explosion in terms of impact will be radiation contamination of the environment for tens of kilometers around.
Fallout
The fireball that appears after the explosion is quickly filled with radioactive particles in huge quantities (products of the decay of heavy nuclei). The particle size is so small that when they enter the upper atmosphere, they can stay there for a very long time. Everything that the fireball reaches on the surface of the earth instantly turns into ash and dust, and then is drawn into the pillar of fire. Flame vortices mix these particles with charged particles, forming a dangerous mixture of radioactive dust, the process of sedimentation of the granules of which lasts for a long time.
Coarse dust settles quite quickly, but fine dust is carried by air currents over vast distances, gradually falling out of the newly formed cloud. Large and most charged particles settle in the immediate vicinity of the EC; ash particles visible to the eye can still be found hundreds of kilometers away. They form a deadly cover several centimeters thick. Anyone who gets close to him risks receiving a serious dose of radiation.
Smaller and indistinguishable particles can “float” in the atmosphere for many years, repeatedly circling the Earth. By the time they fall to the surface, they have lost a fair amount of radioactivity. The most dangerous is strontium-90, which has a half-life of 28 years and generates stable radiation throughout this time. Its appearance is detected by instruments around the world. “Landing” on grass and foliage, it becomes involved in food chains. For this reason, examinations of people located thousands of kilometers from the test sites reveal strontium-90 accumulated in the bones. Even if its content is extremely low, the prospect of being a “landfill for storing radioactive waste” does not bode well for a person, leading to the development of bone malignancies. In regions of Russia (as well as other countries) close to the sites of test launches of hydrogen bombs, an increased radioactive background is still observed, which once again proves the ability of this type of weapon to leave significant consequences.
Video about the hydrogen bomb
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