Manhattan Project

Extracted Attributes

• Cost

  Nearly US$2 billion (equivalent to about $28 billion in 2024)

• Type

  Research and development program / Military project

• Key Leaders

  Major General Leslie Groves, J. Robert Oppenheimer

• Active Years

  1942–1946

• Key Products

  Little Boy (uranium gun-type bomb), Fat Man (plutonium implosion bomb)

• Participants

  United States, United Kingdom, Canada

• Primary Sites

  Los Alamos (New Mexico), Oak Ridge (Tennessee), Hanford (Washington)

• Peak Employment

  Nearly 130,000 people

Timeline

• Albert Einstein signs a letter to President Franklin D. Roosevelt warning of potential German nuclear weapon research, prompting early US interest. (Source: Web Search)

  1939-08-02

• President Roosevelt approves a US Army program to develop an atomic weapon, leading to the establishment of the Manhattan District. (Source: Web Search)

  1942-06-18

• The first nuclear device is successfully detonated during the Trinity test at White Sands Proving Ground in New Mexico. (Source: Wikipedia)

  1945-07-16

• The Little Boy atomic bomb is dropped on Hiroshima, Japan. (Source: Wikipedia)

  1945-08-06

• The Fat Man atomic bomb is dropped on Nagasaki, Japan. (Source: Wikipedia)

  1945-08-09

• The Manhattan Project transfers control of atomic research and production to the newly formed United States Atomic Energy Commission (AEC). (Source: Wikipedia)

  1947-01-01

Manhattan Project

The Manhattan Project was a research and development program undertaken during World War II to produce the first nuclear weapons. It was led by the United States in collaboration with the United Kingdom and Canada. The Manhattan Project employed nearly 130,000 people at its peak and cost nearly US$2 billion (equivalent to about $28 billion in 2024). From 1942 to 1946, the project was directed by Major General Leslie Groves of the U.S. Army Corps of Engineers. Nuclear physicist J. Robert Oppenheimer was the director of the Los Alamos Laboratory that designed the bombs. The Army program was designated the Manhattan District, as its first headquarters were in Manhattan; the name gradually superseded the official codename, Development of Substitute Materials, for the entire project. The project absorbed its earlier British counterpart, Tube Alloys. Over 80 percent of project cost was for building and operating the fissile material production plants. The project proposed both highly enriched uranium and plutonium as fuel for nuclear weapons. Enriched uranium was produced at the Clinton Engineer Works in Tennessee. Plutonium was produced in the world's first industrial-scale nuclear reactors at the Hanford Engineer Works in Washington. These sites were supported by dozens of other facilities across Canada, the US and the UK. The weapons designs were produced at the Los Alamos Laboratory in New Mexico, and resulted in two weapon designs used during the war: Little Boy (enriched uranium gun-type) and Fat Man (plutonium implosion). The Fat Man design was initially a low priority fallback option, as it was complex and required explosive lenses, but in 1944 it was confirmed that plutonium from Hanford was not suitable for a gun-type bomb because of the high proportion of plutonium-240. The first nuclear device ever detonated was an implosion-type bomb during the Trinity test, conducted at White Sands Proving Ground in New Mexico on 16 July 1945. The project was responsible for developing the specific means of delivering the weapons onto military targets, and for the use of the Little Boy and Fat Man bombs in the atomic bombings of Hiroshima and Nagasaki in August 1945. The project was also charged with gathering intelligence on the German nuclear weapon project. Through Operation Alsos, Manhattan Project personnel served in Europe, sometimes behind enemy lines, where they gathered nuclear materials and documents and rounded up German scientists. Despite the Manhattan Project's own emphasis on security, Soviet atomic spies penetrated the program. In the immediate postwar years, the Manhattan Project conducted weapons testing at Bikini Atoll as part of Operation Crossroads, developed new weapons, promoted the development of the network of national laboratories, supported medical research into radiology, and laid the foundations for the nuclear navy. It maintained control over American atomic weapons research and production until the formation of the United States Atomic Energy Commission (AEC) in January 1947.

Web Search Results

• The Manhattan Project | WWII In 2

  to as the Manhattan Project. The Manhattan Project was a nationwide effort by labs and universities to develop fisionable materials and the means to produce an atomic bomb. Los Alamos Scientific Lab in New Mexico was a central location for scientific research and was led by scientists J. Robert Oenheimer and Army Brigadier General Leslie Groves to create isotopes with uranium 235 and plutonium 239. Facilities were built at Hanford Engineering Works in Washington State and Clinton Engineering Works in Oakidge, Tennessee. Thousands of people worked on the Manhattan project, but information was compartmentalized, and a top-seeker classification meant only a few select people understood the project's goal. A uranium based bomb was thought to be a reliable design, but a major challenge was [...] July 16th, 1945, nuclear scientists working for the Manhattan Project successfully detonated the plutoniumbased device in the remote New Mexico desert. The world had entered the atomic age and there was no going back. This is World War II and two. In the 1930s, scientists discovered the possibility of atomic fision, which split the atom, creating a powerful explosive force. After the German invasion of Poland in 1939, Albert Einstein penned a letter to President Franklin Roosevelt warning of the danger if that technology fell into Nazi hands. FDR heeding the warning and by June 1942, he approved a US Army program to develop an atomic weapon. Initially set up office space in Broadway in New York City. The effort was soon referred to as the Manhattan Project. The Manhattan Project was a

• Manhattan Project Background Information and Preservation Work | Department of Energy

  In a national survey at the turn of the millennium, both journalists and the public ranked the dropping of the atomic bomb and the end of the Second World War as the top news stories of the twentieth century. The Manhattan Project is the story of some of the most renowned scientists of the century combining with industry, the military, and tens of thousands of ordinary Americans working at sites across the country to translate original scientific discoveries into an entirely new kind of weapon. When the existence of this nationwide, secret project was revealed to the American people following the atomic bombings of Hiroshima and Nagasaki, most were astounded to learn that such a far-flung, government-run, top-secret operation existed, with physical properties, payroll, and a labor force [...] Resources: The Department has developed and made available to the public — in print, online, and on display — a variety of Manhattan Project historical resources, including histories, websites, reports, and document collections. On July 16, 2013, the 68th anniversary of the Trinity test of the world's first nuclear weapon, the Department launched The Manhattan Project: Resources, a web-based, joint collaboration between the Department’s Office of Classification and its History Program. The site is designed to disseminate information and documentation on the Manhattan Project to a broad audience including scholars, students, and the general public. The Manhattan Project: Resources consists of two parts: 1) a multi-page, easy-to-read history providing a comprehensive overview of the [...] Congress the establishment of a Manhattan Project National Historical Park, with three sites at Oak Ridge, Hanford, and Los Alamos. In December 2014, Congress passed the National Defense Authorization Act of 2015, which included provisions authorizing the Park to be located at the three sites. President Obama signed the National Defense Authorization Act into law on December 19, 2014. On November 10, 2015, Secretary of the Interior Sally Jewell and Secretary of Energy Ernest Moniz signed the Memorandum of Agreement between the two agencies defining the respective roles in creating and managing the park. The agreement included provisions for enhanced public access, management, interpretation, and historic preservation. With the signing, the Manhattan Project National Historical Park

• Manhattan Project - National Park Service

  | Manhattan Project Learn About the Park Learn about Hanford, WA Learn about Los Alamos, NM Learn about Oak Ridge, TN The Manhattan Project was an unprecedented, top-secret World War II government program in which the United States rushed to develop and deploy the world’s first atomic weapons before Nazi Germany. The use of these weapons by the United States against Japan in August 1945 ultimately became one of the most important historical events of the 20th century. The project ushered in the nuclear age and left enduring legacies that echo all around us today. The Manhattan Project took shape at three primary locations across the country: Hanford, Washington; Los Alamos, New Mexico; and Oak Ridge, Tennessee. A man with a long pipe on the left is sitting next to a man in a [...] Color photo of a building in ruins and silhouetted. SHUTTERSTOCK ## Legacies The Manhattan Project was a highly significant chapter in America’s history that ushered in the nuclear age, determined how the next war, the Cold War, would be fought, and served as the organizational model behind the remarkable achievements of American "big science" during the second half of the twentieth century. The project helped develop three communities—Hanford (the Tri-Cities), Los Alamos, and Oak Ridge—that are thriving today and are now part of the Manhattan Project National Historical Park. [...] The United States formally entered World War II after Imperial Japan bombed Pearl Harbor on December 7, 1941. With the US now at war, the Advisory Committee on Uranium concluded that an atomic bomb could be designed, built, and used in time to influence the outcome of the war. To accomplish this task, the Army Corps of Engineers established the Manhattan Engineer District, headed by Brigadier General Leslie Groves, in Manhattan, New York. This focused effort combined military, scientific, and industrial resources. The Manhattan Project largely remained secret even though it involved hundreds of thousands of workers across the country.

• Manhattan Project | Wellerstein | Encyclopedia of the History of Science

  The Manhattan Project remains one of the prototypical examples of a massive and resource-intensive scientific-industrial-military-governmental collaboration that produced world-shattering results in an unusually short amount of time (the production phase of the project ran only 2.5 years, which is still the record for any national nuclear weapons program). As a result, there have been many invocations of the Manhattan Project as a symbol of technoscientific success: there are frequently calls for “Manhattan Projects” for things as diverse as solar power, cybersecurity, and cancer. But invoking the Manhattan Project as a symbol of intensive resource investment ignores many important factors, notably its decidedly undemocratic nature, its extensive use of militarized secrecy, its vast [...] The Manhattan Project, and the atomic bomb itself, could not have been imagined as plausible prior to the discovery of nuclear fission by Otto Hahn, Fritz Strassman, Lise Meitner, and Otto Frisch in the winter of 1938. Nuclear fission — the splitting of heavy nuclei (originally uranium) through the bombardment of neutrons — and the subsequent (early 1939) concept of the nuclear chain reaction provided the first concrete mechanism towards controlling the rate of nuclear reactions and inducing them towards exponential reactions that might cause explosions. For the context of the Manhattan Project, it suffices to note that by the early 1940, scientists in several nations (France, Germany, the United Kingdom, and the United States, with Japan following in 1941 and the Soviet Union in 1942) [...] the subcontracted labor that fed raw resources into the project. Because of the high rate of labor turnover on the project, some 500,000 Americans worked on some aspect of the sprawling Manhattan Project, almost 1% of the entire US civilian labor force during World War II. In 1943, the project was estimated to be consuming approximately over half of all Army construction labor and steel production, and the Oak Ridge site alone used approximately 1% of the electrical power produced for the entire country. The Manhattan Project was responsible for the generation of thousands of new inventions, as represented by patent claims processed in secret by the project, which if filed would have represented some 1% of all patents in force at the end of World War II. And while much attention has been

• Manhattan Project: The Manhattan Project and the Second World War, 1939-1945

  weapon of awesome destructive capability, making clear the importance of basic scientific research to national defense. The Manhattan Project became the organizational model behind the remarkable achievements of American "big science" during the second half of the twentieth century. When President John F. Kennedy announced his goal of putting a man on the moon by the end of the 1960s, it was the Manhattan Project that he invoked for its spirit of commitment and patriotism. [...] Hiroshima, August 6, 1945 The Atomic Bombing of Nagasaki, August 9, 1945 Japan Surrenders, August 10-15, 1945 The Manhattan Project and the Second World War, 1939-1945 The atomic bombings of Hiroshima and Nagasaki and the surrender of Japan were the last acts of the Second World War. The most destructive weapon in the history of combat had helped bring an end to the most destructive conflict in human history. A Frenchman weeps as he watches German troops march into Paris, June 14, 1940.The Manhattan Project and the devastation that its successful outcome wrought are inexplicable outside the context of the Second World War. The project began as a race to acquire the bomb before Nazi Germany did, and the prospects of an atomic bomb in the hands of one of the world's most [...] government, academia, the military, and industry into an organization that took nuclear physics from the laboratory and on to the battlefield with a weapon of awesome destructive capability, making clear the importance of basic scientific research to national defense. The Manhattan Project became the organizational model behind the remarkable achievements of American "big science" during the second half of the twentieth century. When President John F. Kennedy announced his goal of putting a man on the moon by the end of the 1960s, it was the Manhattan Project that he invoked for its spirit of commitment and patriotism. To view the next "event" of the Manhattan Project, proceed to "1945-present: Postscript -- The Nuclear Age." The War Enters Its Final Phase, 1945 Debate Over How to