Hundreds of thousands of famous and forgotten gunsmiths of antiquity fought in search of the ideal weapon, capable of evaporating an enemy army with one click. From time to time, a trace of these searches can be found in fairy tales that more or less plausibly describe a miracle sword or a bow that hits without missing.
Fortunately, technological progress moved so slowly for a long time that the real embodiment of the devastating weapon remained in dreams and oral stories, and later on the pages of books. The scientific and technological leap of the 19th century provided the conditions for the creation of the main phobia of the 20th century. The nuclear bomb, created and tested under real conditions, revolutionized both military affairs and politics.
History of the creation of weapons
For a long time it was believed that the most powerful weapons could only be created using explosives. The discoveries of scientists working with the smallest particles provided scientific evidence that enormous energy can be generated with the help of elementary particles. The first in a series of researchers can be called Becquerel, who in 1896 discovered the radioactivity of uranium salts.
Uranium itself has been known since 1786, but at that time no one suspected its radioactivity. The work of scientists at the turn of the 19th and 20th centuries revealed not only special physical properties, but also the possibility of obtaining energy from radioactive substances.
The option of making weapons based on uranium was first described in detail, published and patented by French physicists, the Joliot-Curies in 1939.
Despite its value for weapons, the scientists themselves were strongly opposed to the creation of such a devastating weapon.
Having gone through the Second World War in the Resistance, in the 1950s the couple (Frederick and Irene), realizing the destructive power of war, advocated for general disarmament. They are supported by Niels Bohr, Albert Einstein and other prominent physicists of the time.
Meanwhile, while the Joliot-Curies were busy with the problem of the Nazis in Paris, on the other side of the planet, in America, the world's first nuclear charge was being developed. Robert Oppenheimer, who led the work, was given the broadest powers and enormous resources. The end of 1941 marked the beginning of the Manhattan Project, which ultimately led to the creation of the first combat nuclear warhead.
In the town of Los Alamos, New Mexico, the first production facilities for weapons-grade uranium were erected. Subsequently, similar nuclear centers appeared throughout the country, for example in Chicago, in Oak Ridge, Tennessee, and research was carried out in California. The best forces of the professors of American universities, as well as physicists who fled from Germany, were thrown into creating the bomb.
In the “Third Reich” itself, work on creating a new type of weapon was launched in a manner characteristic of the Fuhrer.
Since “Besnovaty” was more interested in tanks and planes, and the more the better, he did not see much need for a new miracle bomb.
Accordingly, projects not supported by Hitler moved at a snail's pace at best.
When things started to get hot, and it turned out that the tanks and planes were swallowed up by the Eastern Front, the new miracle weapon received support. But it was too late; in conditions of bombing and constant fear of Soviet tank wedges, it was not possible to create a device with a nuclear component.
The Soviet Union was more attentive to the possibility of creating a new type of destructive weapon. In the pre-war period, physicists collected and consolidated general knowledge about nuclear energy and the possibility of creating nuclear weapons. Intelligence worked intensively throughout the entire period of the creation of the nuclear bomb both in the USSR and in the USA. The war played a significant role in slowing down the pace of development, as huge resources went to the front.
True, Academician Igor Vasilyevich Kurchatov, with his characteristic tenacity, promoted the work of all subordinate departments in this direction. Looking ahead a little, it is he who will be tasked with accelerating the development of weapons in the face of the threat of an American strike on the cities of the USSR. It was he, standing in the gravel of a huge machine of hundreds and thousands of scientists and workers, who would be awarded the honorary title of the father of the Soviet nuclear bomb.
World's first tests
But let's return to the American nuclear program. By the summer of 1945, American scientists managed to create the world's first nuclear bomb. Any boy who has made himself or bought a powerful firecracker in a store experiences extraordinary torment, wanting to blow it up as quickly as possible. In 1945, hundreds of American soldiers and scientists experienced the same thing.
On June 16, 1945, the first ever nuclear weapons test and one of the most powerful explosions to date took place in the Alamogordo Desert, New Mexico.
Eyewitnesses watching the explosion from the bunker were amazed by the force with which the charge exploded at the top of the 30-meter steel tower. At first, everything was flooded with light, several times stronger than the sun. Then a fireball rose into the sky, turning into a column of smoke that took shape into the famous mushroom.
As soon as the dust settled, researchers and bomb creators rushed to the site of the explosion. They watched the aftermath from lead-encrusted Sherman tanks. What they saw amazed them; no weapon could cause such damage. The sand melted to glass in some places.
Tiny remains of the tower were also found; in a crater of huge diameter, mutilated and crushed structures clearly illustrated the destructive power.
Damaging factors
This explosion provided the first information about the power of the new weapon, about what it could use to destroy the enemy. These are several factors:
- light radiation, flash, capable of blinding even protected organs of vision;
- shock wave, a dense stream of air moving from the center, destroying most buildings;
- an electromagnetic pulse that disables most equipment and does not allow the use of communications for the first time after the explosion;
- penetrating radiation, the most dangerous factor for those who have taken refuge from other damaging factors, is divided into alpha-beta-gamma irradiation;
- radioactive contamination that can negatively affect health and life for tens or even hundreds of years.
The further use of nuclear weapons, including in combat, showed all the peculiarities of their impact on living organisms and nature. August 6, 1945 was the last day for tens of thousands of residents of the small city of Hiroshima, then known for several important military installations.
The outcome of the war in the Pacific was a foregone conclusion, but the Pentagon believed that the operation on the Japanese archipelago would cost more than a million lives of US Marines. It was decided to kill several birds with one stone, take Japan out of the war, saving on the landing operation, test a new weapon and announce it to the whole world, and, above all, to the USSR.
At one o'clock in the morning, the plane carrying the "Baby" nuclear bomb took off on a mission.
The bomb, dropped over the city, exploded at an altitude of approximately 600 meters at 8.15 am. All buildings located at a distance of 800 meters from the epicenter were destroyed. The walls of only a few buildings, designed to withstand a magnitude 9 earthquake, survived.
Of every ten people who were within a radius of 600 meters at the time of the bomb explosion, only one could survive. The light radiation turned people into coal, leaving shadow marks on the stone, a dark imprint of the place where the person was. The ensuing blast wave was so strong that it could break glass at a distance of 19 kilometers from the explosion site.
One teenager was knocked out of the house through a window by a dense stream of air; upon landing, the guy saw the walls of the house folding like cards. The blast wave was followed by a fire tornado, destroying those few residents who survived the explosion and did not have time to leave the fire zone. Those at a distance from the explosion began to experience severe malaise, the cause of which was initially unclear to doctors.
Much later, a few weeks later, the term “radiation poisoning” was announced, now known as radiation sickness.
More than 280 thousand people became victims of just one bomb, both directly from the explosion and from subsequent illnesses.
The bombing of Japan with nuclear weapons did not end there. According to the plan, only four to six cities were to be hit, but weather conditions only allowed Nagasaki to be hit. In this city, more than 150 thousand people became victims of the Fat Man bomb.
Promises by the American government to carry out such attacks until Japan surrendered led to an armistice and then to the signing of an agreement that ended World War II. But for nuclear weapons this was just the beginning.
The most powerful bomb in the world
The post-war period was marked by the confrontation between the USSR bloc and its allies with the USA and NATO. In the 1940s, the Americans seriously considered the possibility of striking the Soviet Union. To contain the former ally, work on creating a bomb had to be accelerated, and already in 1949, on August 29, the US monopoly in nuclear weapons was ended. During the arms race, two nuclear tests deserve the most attention.
Bikini Atoll, known primarily for frivolous swimsuits, literally made a splash throughout the world in 1954 due to the testing of a specially powerful nuclear charge.
The Americans, having decided to test a new design of atomic weapons, did not calculate the charge. As a result, the explosion was 2.5 times more powerful than planned. Residents of nearby islands, as well as the ubiquitous Japanese fishermen, were under attack.
But it was not the most powerful American bomb. In 1960, the B41 nuclear bomb was put into service, but it never underwent full testing due to its power. The force of the charge was calculated theoretically, for fear of exploding such a dangerous weapon at the test site.
The Soviet Union, which loved to be the first in everything, experienced in 1961, otherwise nicknamed “Kuzka’s mother.”
Responding to America's nuclear blackmail, Soviet scientists created the most powerful bomb in the world. Tested on Novaya Zemlya, it left its mark in almost all corners of the globe. According to recollections, a slight earthquake was felt in the most remote corners at the time of the explosion.
The blast wave, of course, having lost all its destructive power, was able to circle the Earth. To date, this is the most powerful nuclear bomb in the world created and tested by mankind. Of course, if his hands were free, Kim Jong-un's nuclear bomb would be more powerful, but he does not have New Earth to test it.
Atomic bomb device
Let's consider a very primitive, purely for understanding, device of an atomic bomb. There are many classes of atomic bombs, but let’s consider three main ones:
- uranium, based on uranium 235, first exploded over Hiroshima;
- plutonium, based on plutonium 239, first exploded over Nagasaki;
- thermonuclear, sometimes called hydrogen, based on heavy water with deuterium and tritium, fortunately not used against the population.
The first two bombs are based on the effect of heavy nuclei fissioning into smaller ones through an uncontrolled nuclear reaction, releasing huge amounts of energy. The third is based on the fusion of hydrogen nuclei (or rather its isotopes of deuterium and tritium) with the formation of helium, which is heavier in relation to hydrogen. For the same bomb weight, the destructive potential of a hydrogen bomb is 20 times greater.
If for uranium and plutonium it is enough to bring together a mass greater than the critical one (at which a chain reaction begins), then for hydrogen this is not enough.
To reliably connect several pieces of uranium into one, a cannon effect is used in which smaller pieces of uranium are shot into larger ones. Gunpowder can also be used, but for reliability, low-power explosives are used.
In a plutonium bomb, to create the necessary conditions for a chain reaction, explosives are placed around ingots containing plutonium. Due to the cumulative effect, as well as the neutron initiator located at the very center (beryllium with several milligrams of polonium), the necessary conditions are achieved.
It has a main charge, which cannot explode on its own, and a fuse. To create conditions for the fusion of deuterium and tritium nuclei, we need unimaginable pressures and temperatures at at least one point. Next, a chain reaction will occur.
To create such parameters, the bomb includes a conventional, but low-power, nuclear charge, which is the fuse. Its detonation creates the conditions for the start of a thermonuclear reaction.
To estimate the power of an atomic bomb, the so-called “TNT equivalent” is used. An explosion is a release of energy, the most famous explosive in the world is TNT (TNT - trinitrotoluene), and all new types of explosives are equated to it. Bomb "Baby" - 13 kilotons of TNT. That is equivalent to 13000.
Bomb "Fat Man" - 21 kilotons, "Tsar Bomba" - 58 megatons of TNT. It’s scary to think of 58 million tons of explosives concentrated in a mass of 26.5 tons, that’s how much weight this bomb has.
The danger of nuclear war and nuclear disasters
Appearing in the midst of the worst war of the twentieth century, nuclear weapons became the greatest danger to humanity. Immediately after World War II, the Cold War began, which several times almost escalated into a full-fledged nuclear conflict. The threat of the use of nuclear bombs and missiles by at least one side began to be discussed back in the 1950s.
Everyone understood and understands that there can be no winners in this war.
To contain it, efforts have been and are being made by many scientists and politicians. The University of Chicago, using the input of visiting nuclear scientists, including Nobel laureates, sets the Doomsday Clock a few minutes before midnight. Midnight signifies a nuclear cataclysm, the beginning of a new World War and the destruction of the old world. Over the years, the clock hands fluctuated from 17 to 2 minutes to midnight.
There are also several known major accidents that occurred at nuclear power plants. These disasters have an indirect relation to weapons; nuclear power plants are still different from nuclear bombs, but they perfectly demonstrate the results of using the atom for military purposes. The largest of them:
- 1957, Kyshtym accident, due to a failure in the storage system, an explosion occurred near Kyshtym;
- 1957, Britain, in the north-west of England, security checks were not carried out;
- 1979, USA, due to an untimely detected leak, an explosion and release from a nuclear power plant occurred;
- 1986, tragedy in Chernobyl, explosion of the 4th power unit;
- 2011, accident at the Fukushima station, Japan.
Each of these tragedies left a heavy mark on the fate of hundreds of thousands of people and turned entire areas into non-residential zones with special control.
There were incidents that almost cost the start of a nuclear disaster. Soviet nuclear submarines have repeatedly had reactor-related accidents on board. The Americans dropped a Superfortress bomber with two Mark 39 nuclear bombs on board, with a yield of 3.8 megatons. But the activated “safety system” did not allow the charges to detonate and a disaster was avoided.
Nuclear weapons past and present
Today it is clear to anyone that a nuclear war will destroy modern humanity. Meanwhile, the desire to possess nuclear weapons and enter the nuclear club, or rather, burst into it by knocking down the door, still excites the minds of some state leaders.
India and Pakistan created nuclear weapons without permission, and the Israelis are hiding the presence of a bomb.
For some, owning a nuclear bomb is a way to prove their importance on the international stage. For others, it is a guarantee of non-interference by winged democracy or other external factors. But the main thing is that these reserves do not go into business, for which they were really created.
Video
But this is something we often don’t know. And why does a nuclear bomb explode, too...
Let's start from afar. Every atom has a nucleus, and the nucleus consists of protons and neutrons - perhaps everyone knows this. In the same way, everyone saw the periodic table. But why are the chemical elements in it placed this way and not otherwise? Certainly not because Mendeleev wanted it that way. The atomic number of each element in the table indicates how many protons are in the nucleus of that element's atom. In other words, iron is number 26 in the table because there are 26 protons in an iron atom. And if there are not 26 of them, it is no longer iron.
But there can be different numbers of neutrons in the nuclei of the same element, which means that the mass of the nuclei can be different. Atoms of the same element with different masses are called isotopes. Uranium has several such isotopes: the most common in nature is uranium-238 (its nucleus has 92 protons and 146 neutrons, totaling 238). It is radioactive, but you cannot make a nuclear bomb from it. But the isotope uranium-235, a small amount of which is found in uranium ores, is suitable for a nuclear charge.
The reader may have come across the expressions “enriched uranium” and “depleted uranium”. Enriched uranium contains more uranium-235 than natural uranium; in a depleted state, correspondingly, less. Enriched uranium can be used to produce plutonium, another element suitable for a nuclear bomb (it is almost never found in nature). How uranium is enriched and how plutonium is obtained from it is a topic for a separate discussion.
So why does a nuclear bomb explode? The fact is that some heavy nuclei tend to decay if they are hit by a neutron. And you won’t have to wait long for a free neutron – there are a lot of them flying around. So, such a neutron hits the uranium-235 nucleus and thereby breaks it into “fragments”. This releases a few more neutrons. Can you guess what will happen if there are nuclei of the same element around? That's right, a chain reaction will occur. This is how it happens.
In a nuclear reactor, where uranium-235 is “dissolved” in the more stable uranium-238, an explosion does not occur under normal conditions. Most of the neutrons that fly out from decaying nuclei fly away into the milk, without finding the uranium-235 nuclei. In the reactor, the decay of nuclei occurs “sluggishly” (but this is enough for the reactor to provide energy). In a single piece of uranium-235, if it is of sufficient mass, neutrons will be guaranteed to break up the nuclei, the chain reaction will start as an avalanche, and... Stop! After all, if you make a piece of uranium-235 or plutonium with the mass required for an explosion, it will explode immediately. This is not the point.
What if you take two pieces of subcritical mass and push them against each other using a remote-controlled mechanism? For example, place both in a tube and attach a powder charge to one so that at the right moment one piece, like a projectile, is fired at the other. Here is the solution to the problem.
You can do it differently: take a spherical piece of plutonium and attach explosive charges over its entire surface. When these charges detonate on command from the outside, their explosion will compress the plutonium from all sides, compress it to a critical density, and a chain reaction will occur. However, accuracy and reliability are important here: all explosive charges must go off at the same time. If some of them work, and some don’t, or some work late, no nuclear explosion will result: the plutonium will not be compressed to a critical mass, but will dissipate in the air. Instead of a nuclear bomb, you will get a so-called “dirty” one.
This is what an implosion-type nuclear bomb looks like. The charges, which are supposed to create a directed explosion, are made in the form of polyhedra in order to cover the surface of the plutonium sphere as tightly as possible.
The first type of device was called a cannon device, the second type - an implosion device.
The "Little Boy" bomb dropped on Hiroshima had a uranium-235 charge and a cannon-type device. The Fat Man bomb, detonated over Nagasaki, carried a plutonium charge, and the explosive device was implosion. Nowadays, gun-type devices are almost never used; implosion ones are more complicated, but at the same time they allow you to regulate the mass of the nuclear charge and spend it more rationally. And plutonium has replaced uranium-235 as a nuclear explosive.
Quite a few years passed, and physicists offered the military an even more powerful bomb - a thermonuclear bomb, or, as it is also called, a hydrogen bomb. It turns out that hydrogen explodes more powerfully than plutonium?
Hydrogen is indeed explosive, but not that explosive. However, there is no “ordinary” hydrogen in a hydrogen bomb; it uses its isotopes – deuterium and tritium. The nucleus of “ordinary” hydrogen has one neutron, deuterium has two, and tritium has three.
In a nuclear bomb, the nuclei of a heavy element are divided into nuclei of lighter ones. In thermonuclear fusion, the reverse process occurs: light nuclei merge with each other into heavier ones. Deuterium and tritium nuclei, for example, combine to form helium nuclei (otherwise known as alpha particles), and the “extra” neutron is sent into “free flight.” This releases significantly more energy than during the decay of plutonium nuclei. By the way, this is exactly the process that takes place on the Sun.
However, the fusion reaction is possible only at ultra-high temperatures (which is why it is called thermonuclear). How to make deuterium and tritium react? Yes, it’s very simple: you need to use a nuclear bomb as a detonator!
Since deuterium and tritium are themselves stable, their charge in a thermonuclear bomb can be arbitrarily huge. This means that a thermonuclear bomb can be made incomparably more powerful than a “simple” nuclear one. The “Baby” dropped on Hiroshima had a TNT equivalent of within 18 kilotons, and the most powerful hydrogen bomb (the so-called “Tsar Bomba”, also known as “Kuzka’s Mother”) was already 58.6 megatons, more than 3255 times more powerful "Baby"!
The “mushroom” cloud from the Tsar Bomba rose to a height of 67 kilometers, and the blast wave circled the globe three times.
However, such gigantic power is clearly excessive. Having “played enough” with megaton bombs, military engineers and physicists took a different path - the path of miniaturization of nuclear weapons. In their conventional form, nuclear weapons can be dropped from strategic bombers like aerial bombs or launched from ballistic missiles; if you miniaturize them, you get a compact nuclear charge that does not destroy everything for kilometers around, and which can be placed on an artillery shell or an air-to-ground missile. Mobility will increase and the range of tasks to be solved will expand. In addition to strategic nuclear weapons, we will receive tactical ones.
A variety of delivery systems have been developed for tactical nuclear weapons - nuclear cannons, mortars, recoilless rifles (for example, the American Davy Crockett). The USSR even had a nuclear bullet project. True, it had to be abandoned - nuclear bullets were so unreliable, so complicated and expensive to manufacture and store that there was no point in them.
"Davy Crockett." A number of these nuclear weapons were in service with the US Armed Forces, and the West German Minister of Defense unsuccessfully sought to arm the Bundeswehr with them.
Speaking about small nuclear weapons, it is worth mentioning another type of nuclear weapon - the neutron bomb. The plutonium charge in it is small, but this is not necessary. If a thermonuclear bomb follows the path of increasing the force of the explosion, then a neutron bomb relies on another damaging factor - radiation. To enhance radiation, a neutron bomb contains a supply of beryllium isotope, which upon explosion produces a huge number of fast neutrons.
According to its creators, a neutron bomb should kill enemy personnel, but leave equipment intact, which can then be captured during an offensive. In practice, it turned out somewhat differently: irradiated equipment becomes unusable - anyone who dares to pilot it will very soon “earn” radiation sickness. This does not change the fact that a neutron bomb explosion is capable of hitting an enemy through tank armor; neutron ammunition was developed by the United States specifically as a weapon against Soviet tank formations. However, tank armor was soon developed that provided some kind of protection from the flow of fast neutrons.
Another type of nuclear weapon was invented in 1950, but never (as far as is known) produced. This is the so-called cobalt bomb - a nuclear charge with a cobalt shell. During the explosion, cobalt, irradiated by a stream of neutrons, becomes an extremely radioactive isotope and is scattered throughout the area, contaminating it. Just one such bomb of sufficient power could cover the entire globe with cobalt and destroy all of humanity. Fortunately, this project remained a project.
What can we say in conclusion? A nuclear bomb is a truly terrible weapon, and at the same time it (what a paradox!) helped maintain relative peace between the superpowers. If your enemy has nuclear weapons, you will think ten times before attacking him. No country with a nuclear arsenal has ever been attacked from outside, and there have been no wars between major states in the world since 1945. Let's hope there won't be any.
Structurally, the first atomic bomb consisted of the following fundamental components:
- nuclear charge;
- explosive device and automatic charge detonation system with safety systems;
- the ballistic body of the aerial bomb, which housed the nuclear charge and automatic detonation.
The fundamental conditions that determined the design of the RDS-1 bomb were related to:
- with the decision to preserve as much as possible the basic design of the American atomic bomb tested in 1945;
- it is necessary, in the interests of safety, to carry out the final assembly of the charge installed in the ballistic body of the bomb in the conditions of the test site, immediately before detonation;
- with the ability to bomb RDS-1 from a heavy bomber TU-4.
The atomic charge of the RDS-1 bomb was a multilayer structure in which the active substance, plutonium, was transferred to a supercritical state by compressing it through a converging spherical detonation wave in the explosive.
In the center of the nuclear charge was plutonium, structurally consisting of two hemispherical parts. The mass of plutonium was determined in July 1949, upon completion of experiments to measure nuclear constants.
Great successes have been achieved not only by technologists, but also by metallurgists and radiochemists. Thanks to their efforts, already the first plutonium parts contained small amounts of impurities and highly active isotopes. The last point was especially significant, since short-lived isotopes, being the main source of neutrons, could have a negative impact on the likelihood of a premature explosion.
A neutron fuse (NF) was installed in the cavity of the plutonium core in a composite shell of natural uranium. During 1947-1948, about 20 different proposals were considered regarding the principles of operation, design and improvement of the NC.
One of the most complex components of the first atomic bomb RDS-1 was an explosive charge made from an alloy of TNT and hexogen.
The choice of the outer radius of the explosive was determined, on the one hand, by the need to obtain satisfactory energy release, and, on the other, by the permissible external dimensions of the product and technological production capabilities.
The first atomic bomb was developed in relation to its suspension in the TU-4 aircraft, the bomb bay of which provided the ability to accommodate a product with a diameter of up to 1500 mm. Based on this dimension, the midsection of the ballistic body of the RDS-1 bomb was determined. The explosive charge was structurally a hollow ball and consisted of two layers.
The inner layer was formed from two hemispherical bases made from a domestic alloy of TNT and hexogen.
The outer layer of the RDS-1 explosive charge was assembled from individual elements. This layer, intended to form a spherical converging detonation wave at the base of the explosive and called the focusing system, was one of the main functional units of the charge, which largely determined its tactical and technical performance.
The main purpose of the bomb's automation system was to carry out a nuclear explosion at a given trajectory point. Part of the electrical equipment of the bomb was placed on the carrier aircraft, and its individual elements were placed on the nuclear charge.
To increase the reliability of the product's operation, individual elements of the automatic detonation were made according to a two-channel (duplicate) circuit. In case of failure of the high-altitude fuse systems, a special device (impact sensor) was provided in the bomb design to carry out a nuclear explosion when the bomb hits the ground.
Already at the very initial stage of the development of nuclear weapons, it became obvious that the study of the processes occurring in the charge should follow a computational and experimental path, which made it possible to correct the theoretical analysis based on the results of experiments and experimental data on the gas-dynamic characteristics of nuclear charges.
In general, gas-dynamic testing of a nuclear charge included a number of studies related to setting up experiments and recording fast processes, including the propagation of detonation and shock waves in heterogeneous media.
Studies of the properties of substances at the gas-dynamic stage of the operation of nuclear charges, when the pressure range reaches values of up to hundreds of millions of atmospheres, required the development of fundamentally new research methods, the kinetics of which required high accuracy - up to hundredths of a microsecond. Such requirements led to the development of new methods for recording high-speed processes. It was in the Research Sector KB-11 that the foundations of domestic high-speed photochronography were laid with a scanning speed of up to 10 km/s and a shooting speed of about a million frames per second. The ultra-high-speed recorder developed by A.D. Zakharenkov, G.D. Sokolov and V.K. Bobolev (1948) became the prototype of serial SFR devices developed according to the technical specifications of KB-11 at the Institute of Chemical Physics in 1950.
Note that this photochronograph, driven by an air turbine, already at that time provided an image scanning speed of 7 km/s. The parameters of the serial SFR device (1950), driven by an electric motor, created on its basis are more modest - up to 3.5 km/s.
E.K.Zavoisky |
For the computational and theoretical justification of the performance of the first product, it was fundamentally important to know the parameters of the state of the PV behind the front of the detonation wave, as well as the dynamics of the spherically symmetric compression of the central part of the product. For this purpose, in 1948, E.K. Zavoisky proposed and developed an electromagnetic method for recording the mass velocities of explosion products behind the front of detonation waves, both in a plane and in a spherical explosion.
The distribution of the velocity of the explosion products was carried out in parallel and by the method of pulsed radiography by V.A. Tsukerman and co-workers.
To record fast processes, unique multichannel recorders ETAR-1 and ETAR-2, developed by E.A. Etingof and M.S. Tarasov, with a time resolution close to nanosecond were created. Subsequently, these recorders were replaced by the serially produced OK-4 device developed by A.I. Sokolik (ICP AN).
The use of new methods and new recorders in KB-11 research made it possible, already at the start of work on the creation of atomic weapons, to obtain the necessary data on the dynamic compressibility of structural materials.
Experimental studies of the constants of the working substances included in the physical circuit of the charge created the foundation for the verification of physical concepts of the processes occurring in the charge at the gas-dynamic stage of its operation.
General structure of an atomic bomb
The main elements of nuclear weapons are:
- frame
- automation system
The housing is designed to accommodate a nuclear charge and automation system, and also protects them from mechanical, and in some cases, thermal effects. The automation system ensures the explosion of a nuclear charge at a given point in time and eliminates its accidental or premature activation. It includes:
- safety and cocking system
- emergency detonation system
- charge detonation system
- power supply
- explosion sensor system
The means of delivering nuclear weapons can be ballistic missiles, cruise and anti-aircraft missiles, and aircraft. Nuclear ammunition is used to equip aerial bombs, landmines, torpedoes, and artillery shells (203.2 mm SG and 155 mm SG-USA).
Various systems have been invented to detonate the atomic bomb. The simplest system is an injector-type weapon, in which a projectile made of fissile material crashes into the recipient, forming a supercritical mass. The atomic bomb dropped by the United States on Hiroshima on August 6, 1945, had an injection-type detonator. And it had an energy equivalent of approximately 20 kilotons of TNT.
Nuclear Weapons Museum
The Historical and Memorial Museum of Nuclear Weapons RFNC-VNIIEF (Russian Federal Nuclear Center - All-Russian Research Institute of Experimental Physics) was opened in the city of Sarov on November 13, 1992. This is the first museum in the country that tells about the main stages of creating the domestic nuclear shield. The first exhibits of the museum appeared before its visitors on this day in the building of the former technical school, where the museum is still located.
Its exhibits are samples of products that have become legends in the history of the country's nuclear industry. What the greatest specialists were working on was, until recently, a huge state secret not only for mere mortals, but also for the developers of nuclear weapons themselves.
The museum's exposition contains exhibits from the very first test model in 1949 to the present day.
After the end of World War II, the countries of the anti-Hitler coalition rapidly tried to get ahead of each other in the development of a more powerful nuclear bomb.
The first test, carried out by the Americans on real objects in Japan, heated the situation between the USSR and the USA to the limit. Powerful explosions that thundered through Japanese cities and practically destroyed all life in them forced Stalin to abandon many claims on the world stage. Most Soviet physicists were urgently “thrown” into the development of nuclear weapons.
When and how did nuclear weapons appear?
The year 1896 can be considered the year of birth of the atomic bomb. It was then that the French chemist A. Becquerel discovered that uranium is radioactive. The chain reaction of uranium creates powerful energy, which serves as the basis for a terrible explosion. It is unlikely that Becquerel imagined that his discovery would lead to the creation of nuclear weapons - the most terrible weapon in the whole world.
The end of the 19th and beginning of the 20th century was a turning point in the history of the invention of nuclear weapons. It was during this time period that scientists from around the world were able to discover the following laws, rays and elements:
- Alpha, gamma and beta rays;
- Many isotopes of chemical elements with radioactive properties were discovered;
- The law of radioactive decay was discovered, which determines the time and quantitative dependence of the intensity of radioactive decay, depending on the number of radioactive atoms in the test sample;
- Nuclear isometry was born.
In the 1930s, they were able to split the atomic nucleus of uranium for the first time by absorbing neutrons. At the same time, positrons and neurons were discovered. All this gave a powerful impetus to the development of weapons that used atomic energy. In 1939, the world's first atomic bomb design was patented. This was done by a physicist from France, Frederic Joliot-Curie.
As a result of further research and development in this area, a nuclear bomb was born. The power and range of destruction of modern atomic bombs is so great that a country that has nuclear potential practically does not need a powerful army, since one atomic bomb can destroy an entire state.
How does an atomic bomb work?
An atomic bomb consists of many elements, the main ones being:
- Atomic bomb body;
- Automation system that controls the explosion process;
- Nuclear charge or warhead.
The automation system is located in the body of the atomic bomb, along with the nuclear charge. The design of the housing must be reliable enough to protect the warhead from various external factors and influences. For example, various mechanical, temperature or similar influences, which can lead to an unplanned explosion of enormous power that can destroy everything around.
The task of automation is full control over ensuring that the explosion occurs at the right time, so the system consists of the following elements:
- A device responsible for emergency detonation;
- Automation system power supply;
- Detonation sensor system;
- Cocking device;
- Safety device.
When the first tests were carried out, nuclear bombs were delivered on airplanes that managed to leave the affected area. Modern atomic bombs are so powerful that they can only be delivered using cruise, ballistic or at least anti-aircraft missiles.
Atomic bombs use various detonation systems. The simplest of them is a conventional device that is triggered when a projectile hits a target.
One of the main characteristics of nuclear bombs and missiles is their division into calibers, which are of three types:
- Small, the power of atomic bombs of this caliber is equivalent to several thousand tons of TNT;
- Medium (explosion power – several tens of thousands of tons of TNT);
- Large, the charge power of which is measured in millions of tons of TNT.
It is interesting that most often the power of all nuclear bombs is measured precisely in TNT equivalent, since atomic weapons do not have their own scale for measuring the power of the explosion.
Algorithms for the operation of nuclear bombs
Any atomic bomb operates on the principle of using nuclear energy, which is released during a nuclear reaction. This procedure is based on either the division of heavy nuclei or the synthesis of light ones. Since during this reaction a huge amount of energy is released, and in the shortest possible time, the radius of destruction of a nuclear bomb is very impressive. Because of this feature, nuclear weapons are classified as weapons of mass destruction.
During the process that is triggered by the explosion of an atomic bomb, there are two main points:
- This is the immediate center of the explosion, where the nuclear reaction takes place;
- The epicenter of the explosion, which is located at the site where the bomb exploded.
The nuclear energy released during the explosion of an atomic bomb is so strong that seismic tremors begin on the earth. At the same time, these tremors cause direct destruction only at a distance of several hundred meters (although if you take into account the force of the explosion of the bomb itself, these tremors no longer affect anything).
Factors of damage during a nuclear explosion
The explosion of a nuclear bomb does not only cause terrible instant destruction. The consequences of this explosion will be felt not only by people caught in the affected area, but also by their children born after the atomic explosion. Types of destruction by atomic weapons are divided into the following groups:
- Light radiation that occurs directly during an explosion;
- The shock wave propagated by the bomb immediately after the explosion;
- Electromagnetic pulse;
- Penetrating radiation;
- Radioactive contamination that can last for decades.
Although at first glance a flash of light appears to be the least threatening, it is actually the result of the release of enormous amounts of heat and light energy. Its power and strength far exceeds the power of the sun's rays, so damage from light and heat can be fatal at a distance of several kilometers.
The radiation released during an explosion is also very dangerous. Although it does not act for long, it manages to infect everything around, since its penetrating power is incredibly high.
The shock wave during an atomic explosion acts similarly to the same wave during conventional explosions, only its power and radius of destruction are much greater. In a few seconds, it causes irreparable damage not only to people, but also to equipment, buildings and the surrounding environment.
Penetrating radiation provokes the development of radiation sickness, and the electromagnetic pulse poses a danger only to equipment. The combination of all these factors, plus the power of the explosion, makes the atomic bomb the most dangerous weapon in the world.
The world's first nuclear weapons tests
The first country to develop and test nuclear weapons was the United States of America. It was the US government that allocated huge financial subsidies for the development of new promising weapons. By the end of 1941, many outstanding scientists in the field of atomic development were invited to the United States, who by 1945 were able to present a prototype atomic bomb suitable for testing.
The world's first tests of an atomic bomb equipped with an explosive device were carried out in the desert in New Mexico. The bomb, called "Gadget", was detonated on July 16, 1945. The test result was positive, although the military demanded that the nuclear bomb be tested in real combat conditions.
Seeing that there was only one step left before the victory of the Nazi coalition, and such an opportunity might not arise again, the Pentagon decided to launch a nuclear strike on the last ally of Hitler Germany - Japan. In addition, the use of a nuclear bomb was supposed to solve several problems at once:
- To avoid the unnecessary bloodshed that would inevitably occur if US troops set foot on Imperial Japanese soil;
- With one blow, bring the unyielding Japanese to their knees, forcing them to accept terms favorable to the United States;
- Show the USSR (as a possible rival in the future) that the US Army has a unique weapon capable of wiping out any city from the face of the earth;
- And, of course, to see in practice what nuclear weapons are capable of in real combat conditions.
On August 6, 1945, the world's first atomic bomb, which was used in military operations, was dropped on the Japanese city of Hiroshima. This bomb was called "Baby" because it weighed 4 tons. The dropping of the bomb was carefully planned, and it hit exactly where it was planned. Those houses that were not destroyed by the blast wave burned down, as stoves that fell in the houses sparked fires, and the entire city was engulfed in flames.
The bright flash was followed by a heat wave that burned all life within a radius of 4 kilometers, and the subsequent shock wave destroyed most of the buildings.
Those who suffered heatstroke within a radius of 800 meters were burned alive. The blast wave tore off the burnt skin of many. A couple of minutes later a strange black rain began to fall, consisting of steam and ash. Those caught in the black rain suffered incurable burns to their skin.
Those few who were lucky enough to survive suffered from radiation sickness, which at that time was not only unstudied, but also completely unknown. People began to develop fever, vomiting, nausea and attacks of weakness.
On August 9, 1945, the second American bomb, called “Fat Man,” was dropped on the city of Nagasaki. This bomb had approximately the same power as the first, and the consequences of its explosion were just as destructive, although half as many people died.
The two atomic bombs dropped on Japanese cities were the first and only cases in the world of the use of atomic weapons. More than 300,000 people died in the first days after the bombing. About 150 thousand more died from radiation sickness.
After the nuclear bombing of Japanese cities, Stalin received a real shock. It became clear to him that the issue of developing nuclear weapons in Soviet Russia was a matter of security for the entire country. Already on August 20, 1945, a special committee on atomic energy issues began to work, which was urgently created by I. Stalin.
Although research in nuclear physics was carried out by a group of enthusiasts back in Tsarist Russia, it was not given due attention during Soviet times. In 1938, all research in this area was completely stopped, and many nuclear scientists were repressed as enemies of the people. After nuclear explosions in Japan, the Soviet government abruptly began to restore the nuclear industry in the country.
There is evidence that the development of nuclear weapons was carried out in Nazi Germany, and it was German scientists who modified the “raw” American atomic bomb, so the US government removed from Germany all nuclear specialists and all documents related to the development of nuclear weapons.
The Soviet intelligence school, which during the war was able to bypass all foreign intelligence services, transferred secret documents related to the development of nuclear weapons to the USSR back in 1943. At the same time, Soviet agents were infiltrated into all major American nuclear research centers.
As a result of all these measures, already in 1946, technical specifications for the production of two Soviet-made nuclear bombs were ready:
- RDS-1 (with plutonium charge);
- RDS-2 (with two parts of uranium charge).
The abbreviation “RDS” stood for “Russia does it itself,” which was almost completely true.
The news that the USSR was ready to release its nuclear weapons forced the US government to take drastic measures. In 1949, the Trojan plan was developed, according to which it was planned to drop atomic bombs on 70 of the largest cities of the USSR. Only fears of a retaliatory strike prevented this plan from coming true.
This alarming information coming from Soviet intelligence officers forced scientists to work in emergency mode. Already in August 1949, tests of the first atomic bomb produced in the USSR took place. When the United States learned about these tests, the Trojan plan was postponed indefinitely. The era of confrontation between two superpowers began, known in history as the Cold War.
The most powerful nuclear bomb in the world, known as the Tsar Bomba, belongs specifically to the Cold War period. USSR scientists created the most powerful bomb in human history. Its power was 60 megatons, although it was planned to create a bomb with a power of 100 kilotons. This bomb was tested in October 1961. The diameter of the fireball during the explosion was 10 kilometers, and the blast wave circled the globe three times. It was this test that forced most countries of the world to sign an agreement to stop nuclear testing not only in the earth’s atmosphere, but even in space.
Although atomic weapons are an excellent means of intimidating aggressive countries, on the other hand they are capable of nipping out any military conflicts in the bud, since an atomic explosion can destroy all parties to the conflict.
An atomic bomb is a projectile designed to produce a high-power explosion as a result of a very rapid release of nuclear (atomic) energy.
The principle of operation of atomic bombs
The nuclear charge is divided into several parts to critical sizes so that in each of them a self-developing uncontrolled chain reaction of fission of atoms of the fissile substance cannot begin. Such a reaction will occur only when all parts of the charge are quickly connected into one whole. The completeness of the reaction and, ultimately, the power of the explosion greatly depends on the speed of convergence of the individual parts. To impart high speed to parts of the charge, an explosion of a conventional explosive can be used. If parts of a nuclear charge are placed in radial directions at a certain distance from the center, and TNT charges are placed on the outside, then it is possible to carry out an explosion of conventional charges directed towards the center of the nuclear charge. All parts of the nuclear charge will not only combine into a single whole with enormous speed, but will also find themselves for some time compressed on all sides by the enormous pressure of the explosion products and will not be able to separate immediately as soon as a nuclear chain reaction begins in the charge. As a result of this, significantly greater fission will occur than without such compression, and, consequently, the power of the explosion will increase. A neutron reflector also contributes to an increase in the explosion power for the same amount of fissile material (the most effective reflectors are beryllium< Be >, graphite, heavy water< H3O >). The first fission, which would start a chain reaction, requires at least one neutron. It is impossible to count on the timely start of a chain reaction under the influence of neutrons appearing during the spontaneous fission of nuclei, because it occurs relatively rarely: for U-235 - 1 decay per hour per 1 g. substances. There are also very few neutrons existing in free form in the atmosphere: through S = 1 cm/sq. On average, about 6 neutrons fly by per second. For this reason, an artificial source of neutrons is used in a nuclear charge - a kind of nuclear detonator capsule. It also ensures that many fissions begin simultaneously, so the reaction proceeds in the form of a nuclear explosion.
Detonation options (Gun and implosion schemes)
There are two main schemes for detonating a fissile charge: cannon, otherwise called ballistic, and implosive.
The "cannon design" was used in some first generation nuclear weapons. The essence of the cannon circuit is to shoot a charge of gunpowder from one block of fissile material of subcritical mass (“bullet”) into another stationary one (“target”). The blocks are designed so that when connected, their total mass becomes supercritical.
This detonation method is possible only in uranium ammunition, since plutonium has a two orders of magnitude higher neutron background, which sharply increases the likelihood of premature development of a chain reaction before the blocks are connected. This leads to an incomplete release of energy (the so-called “fizzy”, English). To implement the cannon circuit in plutonium ammunition, it is necessary to increase the speed of connection of the charge parts to a technically unattainable level. In addition, uranium withstands mechanical overloads better than plutonium.
Implosive scheme. This detonation scheme involves achieving a supercritical state by compressing the fissile material with a focused shock wave created by the explosion of a chemical explosive. To focus the shock wave, so-called explosive lenses are used, and the detonation is carried out simultaneously at many points with precision accuracy. The creation of such a system for the placement of explosives and detonation was at one time one of the most difficult tasks. The formation of a converging shock wave was ensured by the use of explosive lenses from “fast” and “slow” explosives - TATV (Triaminotrinitrobenzene) and baratol (a mixture of trinitrotoluene with barium nitrate), and some additives)
