Manhattan Project – A research and development undertaking during World War II that produced the first nuclear weapon. An office in Manhattan district of New York was central in its development

Is that a man in a hat (Manhattan Project) in New York City or a bomb in disguise?

The Manhattan Project was a U.S. government research project that produced the world's first atomic bombs. It began in 1942 and continued right through World War II and beyond.

Scientists had to carry out several lines of research and development simultaneously to ensure that the project achieved success quickly. It was known that Germany already had scientists working on a similar project and if they were successful they could win the war.

The army component of the project was originally referred to as the Manhattan District, but this became shortened to just "Manhattan" as work progressed. The army component had an office in Washington and also in Manhattan, New York. Robert Oppenheimer was head of the Los Alamos Laboratory in the American state of New Mexico, and there was a manufacturing site for bomb components at Oak Ridge in Tennessee, with other sites dotted around the U.S. and Canada.

By the summer of 1945, the original $6,000 dollars authorised for the project had grown to a staggering $2 billion.

The first atomic bomb was exploded at 5.30am on July 16, 1945, at the Alamogordo air base in New Mexico. The bomb generated explosive power equivalent to 15,000 to 20,000 tons of TNT. The shock wave was felt more than 100 miles away and the mushroom cloud reached 7.5 miles in height.

The following month, two further atomic bombs produced by the Manhattan Project were dropped on Hiroshima and Nagasaki in Japan, leading to Japan's surrender a few days later.

Interesting fact: Britain had its own wartime project to develop atomic weapons, codenamed Tube Alloys. Britain was initially reluctant to share its knowledge with the U.S., but when it was realised the country did not have the resources to complete its own project, it agreed to collaborate with America.