Nuclear energy is the energy released by reactions of atomic nuclei. Energy harnessed from such reactions is known as nuclear power, which is are used in many ways such as generating electricity. Somewhere near 13-14% of the entire nations' electricity is derived from nuclear energy. However, nuclear energy not only provides many benefits for humans but results in terrible consequences when this energy is abused. Because of the dangers involved with its use, nuclear energy will likely produce much public conflict in the years to come. Groups such as the World Nuclear Association and the IAEA believe that nuclear energy is an essential energy source that all of humans need due to depleting fossil fuels. Greenhouse International and the NIRS argue that nuclear energy produces the threats don't outweigh its usefulness, largely because nuclear bombs have been a huge issue in 21st century. Also, Greenhouse International asserts that by using the nuclear energy, the environment is contaminated if the nuclear bomb explodes or nuclear plant flows out the nuclear energy. 
In mid-twentieth century, nuclear energy was discovered and was used to construct the atomic bombs, which were the main weapon for the United States to bomb Hiroshima and Nagasaki, Japan. Enrico Fermi was the first person who had a experiment with nuclear fission in 1934. Soon, other scientists could also see that the neutrons split the uranium atom's nucleus. Also, they realizes that if the fission releases more neutrons then, bearable nuclear chain reaction will result. Therefore, many countries' government focused to invest the nuclear energy. The first nuclear reactor made by humans, came to Chicago as part of the Manhattan Project. Because of this Project, the first nuclear weapon was created and named "little boy". Little boy was dropped on Japan during the World War 2 and the war ended by nuclear bomb, little boy. 
Nuclear Fission and Fusion
Nuclear energy can be produced two different types. One is, large nuclei divides by two to release the energy which is the nuclear fission. The other one is, small nuclei combines each other to release the energy which is nuclear fusion.
In this chemical reaction, the nuclei of atoms is divided to release the energy. Mainly, the atomic bomb and nuclear reactor are the examples of the work of nuclear fission. The element of uranium is the most workable element to endure the nuclear fission to make an energy. Uranium is really easy to split by shooting the neutrons. Once a uranium nucleus is divided, many of the neutrons are released and this phenomenon is called chain reaction.
In this particular chemical reaction, the nuclei of atoms is combined together to release the energy. The nuclear fusion is produced only under the very hot conditions, like sun and other stars. Because of nuclear fusion, the Sun and other stars are able to create the heat and light. The hydrogen bomb, which is considered most powerful weapon that human created ever, works by the nuclear fusion. 
Advantages of Nuclear Energy
- The resources of Earth are limited. The nuclear power plant will produce electricity after the oil and coal burn out.
- The nuclear power plant uses less fuel than the one that uses fossil fuels.
- One ton of uranium produces more energy than million tons of coal or barrels of oil do.
- The coal and oil contaminate the air but the nuclear power plants do not contaminate the air.
Disadvantages of Nuclear Energy
Many countries in the world have nuclear bomb more than enough to defend their countries from others or to attack other countries within nuclear bombs. Between Russia and United States, there are approximately 50,000 nuclear weapons. The nuclear weapon is really important and serious problems nowadays and it maximizes the tension among the all nations in the world.
- If nuclear explosion happens, it produces the radiation which harms the cell of human body. Also, radiation strikes the illnesses years after the explosion happened. As an example of explosion of nuclear, The United States dropped a nuclear weapon on Hiroshima and Nagasaki, Japan, during World War 2. It caused the death of approximately 200,000 Japanese people, and currently the illnesses are still going on in Nagasaki and Hiroshima.
- If the fission goes out of control, it leads a nuclear explosion and the emission of huge amounts of radiation.
- Also, the reactor produces huge amounts of nuclear wastes which spew the extremely dangerous radiation.
- In 1986, a large amounts of radiation was out of the reactor in Chernobyl nuclear power plant, Russia. From this dangerous incident, hundred of thousand of people were exposed to radiation. Moreover, a lot of people died within a week because of exposure of radiation. Several years later, many people may die of cancers because of exposure of radiation.
- In 1957, the nuclear wastes exploded at the dump cite in Russia. It caused the death of many people.
Types of Nuclear Weapons
A nuclear weapon is a really dangerous weapon that derives its strong force to explosion from the nuclear reactions, fission or a combination of fission and fusion. Mainly, the nuclear weapons can be divided by two basic types: one is fission weapons and the other one is fusion weapons.
All the types of nuclear weapons get their destructive force from the nuclear fission reactions. Atomic bombs or atom bomb are common examples of types of fission weapons. The main goal in designing the all nuclear weapons is to ensure that a really important portion of the fuel is consumed before the weapon forces to destroy itself. The fission bombs' amount of energy can range from approximately less than a ton of TNT up to of 500,000 tons of TNT.
The fusion nuclear weapon is the other basic types of nuclear weapon. This type of nuclear weapon gets its strong energy from the nuclear fusion reactions. The thermonuclear weapon and hydrogen bombs are the common examples of fusion weapons. The fusion weapons does not rely on the fusion reactions only, it also derives its energy from fission reaction too. Because the fission weapons is used as a trigger for the fusion reactions and the fusion weapons can trigger themselves fission reactions. The fusion weapons do not have any limits on the energy that from thermonuclear weapons. 
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