Plutonium Bomb

The plutonium bomb, or "Fat Man", was the second and larger atomic bomb to be dropped during World War II. It was dropped on Nagasaki, Japan, on the morning of August 9, 1945, and even though it missed its target by two and a half miles, it still managed to kill an estimated 70,000-100,000 people, some of whom died instantly, and a great many of whom died later from injuries and radiation-induced sickness.

## History of the Project[edit]

Because it is not found abundantly in nature, the isotope used in making atomic bombs, Plutonium-239, is made in laboratories. It is made from uranium-238 using a breeder reactor. There are two laboratories in the United States that manufacture Pu-239; they are located in Savannah River Plant, South Carolina, and Hanford, Washington. This bomb was first made after the United States discovered that Germany was trying to build atomic weapons, and started research of their own. This bomb consists of a small subatomic sphere of Pu-239 surrounded by a tamper. A tamper is a dense material, in this case U-238 or beryllium, depending on the bomb, that keeps the neutrons from escaping until the explosion occurs. Surrounding the tamper are "conventional explosives". This explosion is possible because Pu-239 is an unstable isotope of plutonium, also called a radioactive isotope. Radioactive refers to the energy and extra neutrons being constantly released by the plutonium. They are released because the plutonium is unstable, and the nucleus is constantly about to fall apart, or decay. When it decays, it splits into two smaller and more stable atoms, releasing unneeded energy and neutrons. Normally, the energy and neutrons can escape, and no explosion occurs. However, when the conventional explosives are detonated, they force the plutonium into a densely packed sphere. The tamper holds the plutonium in this dense state, and now when the neutrons are released, they cannot go anywhere without hitting another atom and causing it to split. This chain reaction occurs in a split second, and eventually the released energy causes an explosion.