August 20, 2022

A nuclear weapon (formerly also an atomic weapon) is a bomb that gets its explosive power from nuclear fission or nuclear fusion. A single nuclear weapon can destroy or severely disable an entire city, making it one of the most dangerous weapons in the world. Most of the destructive power of a nuclear weapon comes from the effect of pressure and heat. In addition to these, nuclear weapons have a significant, though generally less destructive, radiation effect than those mentioned above. The radiation effect can cause diseases in the exposed population, such as radiation sickness or cancer, Today, nuclear weapons are known to be in use in the United States, Russia, Great Britain, France, China, India, North Korea and Pakistan. These countries have declared themselves to be nuclear weapon states. In addition, some countries may possess nuclear weapons, but have not publicly acknowledged them or the claims have not been able to be verified. For example, Israel is estimated to have a significant number of nuclear weapons. South Africa has voluntarily given up its nuclear weapons. Nuclear weapons have been detonated more than two thousand times. Two of these explosions took place in World War II, the rest were carried out in nuclear tests. The US bombed the Japanese cities of Hiroshima and Nagasaki in World War II. The largest nuclear weapon ever detonated is the Tsar bomb detonated by the Soviet Union on Novaya Zemlya in 1961. In addition to the military use of nuclear weapons, the threat is the risk of a nuclear weapon accident related to manufacturing, storage and transportation. In addition to military use, nuclear explosives have also been used or proposed for use in various peaceful applications.

History of Nuclear Weapons

The principle of the atomic bomb was presented in 1934 by the physicist Leó Szilárd. Practically working nuclear weapons were developed during the Second World War. In 1939, the United States started the Manhattan Project, which resulted in the detonation of atomic bombs in Hiroshima and Nagasaki in Japan in August 1945.

Fission Bombs

Atomic bombs get their explosive power from fission, where heavy nuclei (uranium or plutonium) split into lighter atomic nuclei when bombarded with neutrons. When the neutrons produced in the fission of nuclei split new nuclei again, an explosive chain reaction is created in which an immense amount of energy is released. Sometimes atomic bomb means just a fission bomb, other times any nuclear weapon. This confuses the concepts somewhat.

The physical basis of a fission bomb

An atomic bomb is based on a nuclear reaction. Atomic nuclei undergo changes if they are bombarded with particles of suitable energy, usually neutrons. In some cases, the atom absorbs this free neutron and becomes unstable itself. Then the atom splits and emits radiation and new free neutrons, which in turn break more nuclei. The heaviest atomic nuclei split the most easily because they are inherently unstable. The actual explosion is caused by the fact that, mainly due to the huge X-ray pulse, the surrounding air heats up quickly, so it expands explosively and sends out a shock wave. The explosion of an atomic bomb is seen as a flash, followed by the appearance of a fireball and finally the creation of a mushroom cloud. The temperature of the atomic bomb's fireball is over ten million degrees. By no means all substances fission, i.e. split when bombarded with neutrons, but only the heaviest substances. When lighter substances capture neutrons, new elements are created, among other things. There are a few substances suitable for fission bombs: uranium (U) occurs in nature, and plutonium (Pu) can be produced in a nuclear reactor. There are other similar substances, but they are not known to be used in nuclear weapons.


Isotopes are subspecies of elements with different masses, which differ from each other based on the number of neutrons in the nucleus. Uranium has several isotopes, of which only certain are suitable for nuclear pol