Slide 1

The Atomic Bomb Slide 2 What do you know about the atomic bomb? Why should you care about the atomic bomb? Slide 3 Who Built the Atomic Bomb? Why did they build it? Why was it used? How was the decision made to use it? Slide 4 Albert Einstein Franklin D. Roosevelt J. Robert Oppenheimer Harry Truman Slide 5 Albert Einstein Father of Quantum Physics-E=mc 2 Letter to Roosevelt This new phenomenon would also lead to the construction of bombs, and it is conceivable... that extremely powerful bombs of a new type may thus be constructed. Slide 6 Franklin D. Roosevelt President of the United States, 1932-1945 The Uranium Committee (1939) Office of Scientific Research and Development (1941) The Manhattan Project (1942) Slide 7 J. Robert Oppenheimer Scientific director of Manhattan Project Father of the Atomic Bomb Los Alamos National Laboratory Atomic Energy Commission Accused of Communist Ties. Slide 8 Harry Truman Became President upon Roosevelts death Gave the order to drop the atomic bombs on Hiroshima and Nagasaki Slide 9 Little Boy Gun-type uranium fission bomb Yield: 15 kilotons Dropped on Hiroshima, 6 August 1945 Casualties: 140,000 Fat Man Implosion-type plutonium fission bomb Yield: 21 kilotons Dropped on Nagasaki, 9 August 1945 Casualties: 90,000 Slide 10 Trinity Alamogordo, New Mexico July 16, 1945 First human-made nuclear explosion Implosion-type weapon 20 kiloton yield News of successful test relayed to Truman at Potsdam Potsdam Declaration Slide 11 And now I am become Death, destroyer of worlds. - J. Robert Oppenheimer Slide 12 Hiroshima, 25 July 1945 Slide 13 Hiroshima, 11 August 1945 Slide 14 Slide 15 Slide 16 Why Did Truman Drop the Bomb? To make an invasion of Japan unnecessary To intimidate the Soviet Union "Having found the bomb we have used it. We have used it against those who attacked us without warning at Pearl Harbor, against those who have starved and beaten and executed American prisoners of war, against those who have abandoned all pretense of obeying international laws of warfare. We have used it in order to shorten the agony of war, in order to save the lives of thousands and thousands of young Americans. -Harry Truman Slide 17 Make an Invasion of Japan Unnecessary Okinawa (March-June, 1945) Casualties-American: 13,000 killed, 39,000 wounded; Japanese, 131,000 killed; Civilians, 100,000 killed. Projected Casualties for Operation Downfall: 46,000-280,000 killed, up to a million total Slide 18 The Soviet Union Divided Europe Soviet numerical superiority Slide 19