The atomic bombs were dropped first on Hiroshima on August 6th and then on Nagasaki on August 9th in 1945.

The number of deaths in Hiroshima by the end of 1945 was about 140 thousand, and in Nagasaki, about 74 thousand.

When uranium and plutonium are bombarded with neutrons, the atomic nuclei undergo fission and radiate energy. During this fission, neutrons are released, causing additional fissions. The nuclear fissions repeated over an extremely short moment produce enormous energy instantly. This reaction is used to create the explosion of atomic bombs.

America started to study the atomic bomb, fearing that Germany might have made some progress on it, and then began preparations to create the bombs in 1942. This was named the “Manhattan Project,” which secretly progressed at a huge expense. On July 16th, 1945, it succeeded in the first atomic bomb explosion experiment in the Alamogordo desert, New Mexico, marking the first time in human history.

Finally, the time came when the bombs were actually used in the war.

On August 6th, an atomic bomb named “Little Boy” was dropped on Hiroshima.

On August 9th, another atomic bomb named “Fat Man,” larger than the first one, was dropped on Nagasaki.

The United States claimed that it was necessary to use the atomic bombs to end the war as soon as possible. However, it is said there may have been other reasons: “To show the achievement of the Manhattan Project, which required a huge amount of money.” “To show the USSR the threat of atomic bombs and assert superiority in the postwar world.”

After Hiroshima and Nagasaki, the development of nuclear weapons never stopped. Instead, it intensified due to the rivalry between the US and the USSR. At its peak, about 70,000 weapons were ready to be used. The world was on the brink of human extinction until the collapse of the USSR. The number is declining, but there is still no way to eliminate nuclear weapons from the earth. There are more than 13,000 nuclear weapons now.

As of 2019, eight countries owned nuclear weapons: China, France, Russia, the UK, the USA, India, Pakistan, and North Korea. Israel does not announce it openly, but it is believed to own some.