LECTURE #04 : Nuclear Weapons Tests of the United States: LECTURE #04 : Nuclear Weapons Tests of the United States


U.S. Nuclear Testing: U.S. Nuclear Testing After the the first three nuclear weapon detonations (Trinity, Hiroshima, and Nagasaki) and the end of WWII there was a global debate about what should be done concerning nuclear weapons. On Jan. 24, 1946 the United Nations created the Atomic Energy Commission (AEC)


U.S. Nuclear Testing: U.S. Nuclear Testing The mandate for the AEC was: “to deal with problems raised by the discovery of nuclear energy” Remember that the UN was a very big deal at the end of WWII


U.S. Nuclear Testing: U.S. Nuclear Testing Because of disagreements between the Soviet Union and the U.S. the AEC was unable to reach any kind of agreement or treaty. On June 14, 1946 the U.S. proposed the Baruch plan in speech given by US financier Bernard Baruch.


The Baruch Plan: The Baruch Plan The text of Baruch’s speech can be found at the following link: Baruch Plan


The Baruch Plan: The Baruch Plan The Baruch Plan called for international ownership and control over all nuclear resources. Under the plan the US would give up its nuclear weapons after the rest of the world’s countries had ceded their nuclear programs to international control.


The Baruch Plan: The Baruch Plan The USSR wanted the US to turn over its nuclear weapons before the rest of the countries turned over their nuclear materials and programs. These differences were not resolvable and the Baruch Plan failed.


US Nuclear Tests: US Nuclear Tests On June 30, 1946 (two weeks after the Baruch Speech to the UN) the United States carried out the first non-wartime test of a nuclear weapon with operation Crossroads. Crossroads consisted of two nuclear explosions in the Bikini atoll in the middle of the Pacific.


US Nuclear Tests: US Nuclear Tests


US Nuclear Tests: US Nuclear Tests The intent of Operation Crossroads was to test the effect of nuclear weapons on a group of Japanese naval vessels that had been captured. The first test, ABLE, was an airdrop, and the second test, BAKER, was detonated underwater. Both were about 20 kt.


US Nuclear Tests: US Nuclear Tests


US Nuclear Tests: US Nuclear Tests The second group of tests were carried out in mid-1948 near Enewetak Atoll in the Marshall Islands (middle of the Pacific) under the name operation Sandstone. The 3 tests were used to determine more efficient ways of designing weapons (weapons that required less fissionable material).


US Nuclear Tests: US Nuclear Tests Marshall Islands Radioecology Program


US Nuclear Tests: US Nuclear Tests Then in 1949 the USSR detonated its first nuclear weapon. The US was completely surprised by this, thinking the Soviets were about a decade away. The Soviets used information from Klaus Fuchs (a British scientist who worked at Los Alamos) to jump ahead.


US Nuclear Tests: US Nuclear Tests This incident, coupled with the Communist takeover of China, the Soviet domination of Eastern Europe, and the outbreak of the Korean War, caused the US to have a new sense in urgency in developing and producing nuclear weapons. The US created the Nevada Test Site and began a serious effort at developing a hydrogen bomb.


US Nuclear Tests: US Nuclear Tests On May 8, 1951 the US carried out the first thermonuclear explosion (not really a bomb) at the Enewetak atoll in the Pacific. In had a yield of 225 kt, about tens times the size of Hiroshima.


US Nuclear Tests: US Nuclear Tests On October 31, 1952 the US detonated the first actual thermonuclear device (bomb) with the codename “MIKE” It had a yield of 10.4 megatons! This is about 500 times bigger than the Hiroshima bomb. At this point a full-scale arms race between the US and the USSR was occurring.


US Nuclear Tests: US Nuclear Tests The first underground nuclear weapons tests was carried out on 9/19/57 under the codename RAINIER. It convinced the US that it was possible to test and develop weapons underground and so avoid contamination in the atmosphere.


US Nuclear Tests: US Nuclear Tests Although the arms race was thriving there was still anti-nuclear sentiment. President Eisenhower announced a unilateral moratorium for 10/31/1958 and the USSR followed suit.


US Nuclear Tests: US Nuclear Tests However in August of 1961 the USSR announced it was resuming testing and the US quickly followed suit. The Cuban Missile Crisis occurred in October of 1962 and the world came pretty close to all-out nuclear war.


US Nuclear Tests: US Nuclear Tests In 1963 the US, Britain, and the USSR signed the Limited Test Ban Treaty This treaty outlawed nuclear weapons testing anywhere other than underground Why is this important to this class ???


US Nuclear Tests: US Nuclear Tests The next big treaty was signed in 1974 and called the “Threshold Test-Ban Treaty” It basically placed an upper limit on the size of nuclear weapons tests. Various arms reducing treaties occur in the 1980s and 1990s. Next big treaty is the CTBT.


US Nuclear Tests: US Nuclear Tests From 1945-1992 the United States has carried out 1020 nuclear tests: Underground : 815 Atmospheric: 206 Underwater: 5 Outer Space: 4


US Nuclear Tests: US Nuclear Tests There were a total of 12 tests carried out using rockets. Most of these are listed with altitudes of “tens of kilometers” However the three Operation Argus tests (1958) were done at altitudes of over 300 miles; and Starfish Prime in 1962 occurred at an altitude of about 250 miles.


US Nuclear Tests: US Nuclear Tests The different categories for atmospheric tests include: airburst, airdrop, balloon, barge, rocket, surface, and tower


US Nuclear Tests: US Nuclear Tests The US has conducted tests in 17 distinct geographical locations including: various Pacific islands, over the South Atlantic Ocean, Nevada, New Mexico, Mississippi, Colorado, and Alaska