Upshot–Knothole ''Annie'' was a

nuclear weapons test Nuclear weapons tests are experiments carried out to determine nuclear weapons' effectiveness, yield, and explosive capability. Testing nuclear weapons offers practical information about how the weapons function, how detonations are affected by ...

conducted by the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

as part of

Operation Upshot–Knothole Operation Upshot–Knothole was a series of eleven nuclear test shots conducted in 1953 at the Nevada Test Site. It followed ''Operation Ivy'' and preceded ''Operation Castle''. Over 21,000 soldiers took part in the ground exercise Desert Ro ...

. It took place at the

Nevada Test Site The Nevada National Security Site (N2S2 or NNSS), known as the Nevada Test Site (NTS) until 2010, is a United States Department of Energy (DOE) reservation located in southeastern Nye County, Nevada, about 65 miles (105 km) northwest of the ...

on 17 March 1953, and was nationally televised. The live TV coverage was recorded on a

kinescope Kinescope , shortened to kine , also known as telerecording in Britain, is a recording of a television program on motion picture film, directly through a lens focused on the screen of a video monitor. The process was pioneered during the 194 ...

, so it is a rare record of the sound an actual atomic bomb makes. Operation Doorstep was a civil defense study conducted by the Federal Civil Defense Administration in conjunction with ''Annie''. It studied the effect of the nuclear blast on two wooden frame houses, fifty automobiles and eight bomb shelters designed for residential use. The administration concluded that a car would be "relatively safe" from a small nuclear bomb at least ten blocks away if windows were left open to prevent the car collapsing on its occupants. The homes in the study were constructed in such a way as to minimize the thermal effects of Annie, with an eye towards determining if, in the absence of fire, the basement of the closer home — from the hypocenter — might shelter its occupants, while the second — at — could remain standing.Eden (2004), pp. 166-167. Both homes performed as expected under the conditions of their construction.

References

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