The discovery by Albert Einstein of the ability of substances to release large amounts of energy at the atomic level marked the beginning of nuclear physics. In the 1930s, researchers simulated an airborne nuclear explosion in the laboratory, but the experience gained endangered peaceful life on Earth.
Operation principle
For an air nuclear explosion, you need to create certain conditions that provoke a detonation. Usually, TNT or RDX are used as detonators, under the influence of which a radioactive substance (usually uranium or plutonium) is compressed to a critical mass within 10 seconds, and then a powerful release of energy occurs. If the bomb is thermonuclear, then the process of transformation of light elements into heavier ones takes place in it. The energy released in this case carries with it an even more powerful explosion.
A nuclear reactor can also be used for peaceful purposes, since fission can be controlled. For this, devices that absorb neutrons are used. The processes occurring in such an installation are always in equilibrium. Evenif there are any minor changes in the parameters, the system extinguishes them in time and returns to the operating mode. In emergency situations, elements are automatically reset to stop the chain reaction.
First experience
Discovered by Einstein and further studied by nuclear physicists, the release of energy interested not only scientists, but also the military. The possibility of obtaining new weapons that could create powerful explosions from a small amount of material led to experiments with radioactive elements.
Physically, the possibility of an explosion with a significant damaging effect was proved by the French scientist Joliot-Curie. He discovered a chain reaction, which became a powerful source of energy. Further, he planned to conduct experiments with deuterium oxide, but in the conditions of the Second World War it was impossible to do in France, so in the future, British scientists took up the development of atomic weapons.
The first explosive device was tested in the summer of 1945 in America. By today's standards, the bomb had little power, but at that time the resulting effect exceeded all expectations. The force of the explosion and the impact on the surrounding area were enormous.
Results
Tests were carried out to determine the characteristics of an air-nuclear explosion. Those present subsequently described what they saw. They observed a bright luminous dot at a distance of several hundred kilometers. Then it turned into a huge ball, a very loud sound was heard, and for kilometersshock wave rolled over. The balloon exploded, leaving behind a twelve-kilometer cloud in the shape of a mushroom. A crater remained at the site of the explosion, extending tens of meters in depth and width. The ground around him for several hundred meters turned into lifeless, pitted soil.
The air temperature during the nuclear explosion increased significantly, and the atmosphere itself seemed to become denser. This was felt even by eyewitnesses who were far from the epicenter in the shelter. The scale of what they saw was amazing, because no one imagined what power they would face. It was concluded that the tests were successful.
The damaging factors of an air nuclear explosion
The military immediately realized that a new weapon could decide the outcome of any war. But at that time no one thought about the impact of the damaging factors of a nuclear explosion. Scientists paid attention only to the most obvious of them:
- shock wave;
- light emission.
At that time no one knew about radioactive contamination and ionizing radiation, although later it was penetrating radiation that turned out to be the most dangerous. So, if devastation and destruction were localized at a distance of several hundred meters from the epicenter of an air nuclear explosion, then the area of dispersion of radiation decay products extended for hundreds of kilometers. A person received the first exposure, which was subsequently aggravated by radiation fallout in nearby areas.
Also, scientists did not yet know that under the influenceThe air shock wave of a nuclear explosion generates an electromagnetic pulse that can disable all electronics at a distance of hundreds of kilometers. Thus, the first testers could not even imagine how powerful the weapon was created, and how catastrophic the consequences of its use could be.
Types of explosions
Air nuclear explosions are carried out at the height of the troposphere, that is, within 10 km above the earth's surface. But besides them, there are other types, for example:
- Terrestrial or above-water conducted on the surface of the earth or water, respectively. A fireball that expands from a flash, while it looks like the sun rising from behind the horizon.
- High- altitude, conducted in the atmosphere. At the same time, the luminous flash has a very large size, it hangs in the air and does not touch the earth or water surfaces.
- Underground or underwater occur in the thickness of the earth's crust or at depth. Usually there is no flash.
- Space. These occur hundreds of kilometers from the globe, outside the circumplanetary space and are accompanied by a cloud of luminous molecules.
Different types differ not only in flash, but also in other external characteristics, as well as damaging factors, the intensity of the explosion, its results and consequences.
Ground testing
The first bombs were tested directly on the surface of the earth. It is these types of explosions that are accompanied by a distinct mushroom cloud inair and a crater extending for several tens or even hundreds of meters in the soil. A ground explosion looks the most frightening, since a cloud hovering low above the ground attracts not only dust, but also a significant part of the soil, which makes it almost black. Soil particles mix with chemical elements and then fall to the ground, which makes the area radioactively contaminated and completely uninhabitable. For military purposes, this can be used to destroy powerful buildings or objects, infect vast territories. The destructive effect is the most powerful.
Surface explosions
Tests are also carried out above the surface of the water surface. In this case, the cloud will consist of water dust, which reduces the intensity of light radiation, but carries radioactive particles over great distances, as a result of which they can fall out with precipitation a thousand kilometers from the test site.
For military purposes, this can be used to destroy naval bases, ports and ships, or to contaminate waters and coasts.
Air explosions
This species can be produced at a large distance from the ground (in which case it is called high) or at a small distance (low). The higher the explosion occurs, the less the rising cloud resembles the shape of a mushroom, since the column of dust from the ground does not reach it.
Flash in this form is very bright, so it can be seen hundreds of kilometers from the epicenter. A fireball exploding from it with a temperature measured inmillions of degrees Celsius, rises up and sends out powerful light radiation. All this is accompanied by a loud sound, vaguely reminiscent of thunder.
As the ball cools, it transforms into a cloud, which creates a stream of air that picks up dust from the surface. The resulting pillar can reach the cloud if it is not very high above the ground. As the cloud begins to dissipate, the air flow weakens.
As a result of such an explosion, objects in the air, structures, and people in its vicinity can be hit.
Combat use
Hiroshima and Nagasaki are the only cities against which nuclear weapons were used. The tragedy that happened there was unparalleled.
Residents experienced the effect of an airborne nuclear explosion initiated at a short distance from the surface of the earth and classified as low. At the same time, the infrastructure was completely destroyed, about 200 thousand people died. Two-thirds of them died instantly. Those who were in the epicenter, disintegrated into molecules from the monstrous temperatures. Light emission from them left shadows on the walls.
People who were further from the epicenter died from the shock wave and gamma radiation of a nuclear explosion. Some of the survivors received a lethal dose of radiation, but doctors did not yet know about radiation sickness, so no one understood why, after imaginary signs of recovery, the condition of patients deteriorated. Physicians considered itdysentery, but within 3-8 weeks, patients who developed severe vomiting died. The strange disease of the survivors of the atomic bombings of Hiroshima and Nagasaki was the impetus for the start of research in the field of nuclear medicine.
High- altitude explosions
After the bombing of Japanese cities, nuclear weapons were not used for combat purposes, but research on their capabilities continued in various places. Atmospheric exercises made it possible to understand what happens when an explosion occurs at a height. It turned out that when the center is located 10 km from the earth's surface, a relatively small wave of a nuclear explosion arises, but light and radiation radiation increase at the same time. The higher the explosion was made, the stronger the ionization increases, which is accompanied by the failure of radio equipment.
From the surface, it all looks like a big bright flash, followed by a cloud of evaporating molecules of hydrogen, carbon and nitrogen. The air flow does not reach the ground, so there is no dust column. Also, there is practically no contamination of the territory, since air masses move weakly at high altitude, so the purpose of such a nuclear explosion may be to destroy aircraft, missiles or satellites.
Underground tests
Recently, there has been an agreement between countries regulating nuclear testing and requiring them to be carried out only underground, which minimizes pollution and uninhabitable areas formed around the test sites.
Underground tests are considered the least dangerous, since the actionall the damaging factors account for the breed. At the same time, it is impossible to see luminous flashes or a mushroom cloud, only a column of dust remains from it. But the shock wave leads to an earthquake and collapse of the soil. Usually it is used for peaceful purposes, for solving national economic problems. For example, this way you can destroy mountain ranges or form artificial reservoirs.
Underwater testing
Explosions under water have more dire consequences. First, a column of spray appears, rising to a cloud of radioactive fog. At the same time, meter-long waves are formed on the surface of the water, destroying ships and underwater structures. Then there is contamination of the surrounding areas due to a dispersing cloud, pouring radioactive rain.
Protective measures
A nuclear explosion kills everything in its path and destroys all material objects. People caught in its epicenter have no way to escape, they instantly burn to the ground. The bomb shelter is absolutely useless, as it will be destroyed immediately.
Only those who are far enough away from the explosion can escape. At a distance of more than 1-3 km from the epicenter, it is possible to avoid the impact of the shock wave, but for this it is necessary to quickly find a reliable shelter as soon as a bright flash occurs. A person has from 2 to 8 seconds to do this, depending on the distance. In the shelter, a direct hit of gamma radiation will not occur, but there is still a very high probability of radioactive contamination. You can reduce the risk of radiation sickness by using personal protective equipment and avoiding contact withany items on the territory.
Nuclear weapons are one of the most terrible inventions of mankind. Used for peaceful purposes, it can be of great benefit, but its military use is a terrible threat to life on earth. The chain reaction that has started cannot be stopped, so there is a nuclear disarmament treaty designed to protect the planet from catastrophe.
