Operation Upshot-Knothole was a series of eleven nuclear test shots conducted in 1953 at the Nevada Test Site

Nevada Test Site

The Nevada National Security Site , previously the Nevada Test Site , is a United States Department of Energy reservation located in southeastern Nye County, Nevada, about northwest of the city of Las Vegas...

.

Over twenty-one thousand soldiers took part in the ground exercise Desert Rock V in conjunction with the Grable shot. Grable was a 280mm shell fired from the “Atomic Cannon

Nuclear artillery

Nuclear artillery is a subset of limited-yield tactical nuclear weapons, in particular those weapons that are launched from the ground at battlefield targets...

” and was viewed by a number of high-ranking military officials.

Operation Upshot-Knothole followed Operation Ivy

Operation Ivy

Operation Ivy was the eighth series of American nuclear tests, coming after Tumbler-Snapper and before Upshot-Knothole. Its purpose was to help upgrade the U.S. arsenal of nuclear weapons in response to the Soviet nuclear weapons program...

 and preceded Operation Castle

Operation Castle

Operation Castle was a United States series of high-energy nuclear tests by Joint Task Force SEVEN at Bikini Atoll beginning in March 1954...

. The test series was notable as containing the first time an atomic artillery shell was fired (Shot Grable), the first two shots (both fizzles

Fizzle (nuclear test)

In nuclear weapons, a fizzle occurs when the testing of a nuclear bomb fails to meet its expected yield. The reason for the failure can be linked to improper bomb design, poor construction, or lack of expertise. All countries that have had a nuclear weapons testing program have experienced fizzles...

) by University of California Radiation Laboratory—Livermore (now Lawrence Livermore National Laboratory

Lawrence Livermore National Laboratory

The Lawrence Livermore National Laboratory , just outside Livermore, California, is a Federally Funded Research and Development Center founded by the University of California in 1952...

), and for testing out some of the thermonuclear components that would be used for the massive thermonuclear series of Operation Castle.

The individual shots were:

Upshot-Knothole test blasts

Test name	Date	Location	Yield	Note
Annie Upshot-Knothole Annie Upshot-Knothole Annie was a nuclear weapons test conducted by the United States as part of Operation Upshot-Knothole. It took place at the Nevada Test Site on 17 March, 1953, and was nationally televised....	17 March 1953	Nevada Test Site	16 kilotons
Nancy	24 March 1953	Nevada Test Site	24 kilotons
Ruth	31 March 1953	Nevada Test Site	0.2 kilotons	First UCRL Lawrence Livermore National Laboratory The Lawrence Livermore National Laboratory , just outside Livermore, California, is a Federally Funded Research and Development Center founded by the University of California in 1952...  device, uranium hydride device Uranium hydride bomb The uranium hydride bomb was a variant design of the atomic bomb, that was first suggested by Robert Oppenheimer in 1939 and advocated and tested by Edward Teller. It used deuterium, an isotope of hydrogen, as a neutron moderator in a U235-deuterium compound. The chain reaction is a slow nuclear... , fizzle Fizzle (nuclear test) In nuclear weapons, a fizzle occurs when the testing of a nuclear bomb fails to meet its expected yield. The reason for the failure can be linked to improper bomb design, poor construction, or lack of expertise. All countries that have had a nuclear weapons testing program have experienced fizzles...
Dixie Upshot-Knothole Dixie Upshot-Knothole Dixie was the fourth test-firing of Operation Upshot-Knothole, an atomic weapons test series conducted in 1953 by the United States at the Nevada Test Site....	6 April 1953	Nevada Test Site	11 kilotons
Ray	11 April 1953	Nevada Test Site	0.2 kilotons	Second UCRL Lawrence Livermore National Laboratory The Lawrence Livermore National Laboratory , just outside Livermore, California, is a Federally Funded Research and Development Center founded by the University of California in 1952...  device, uranium hydride device Uranium hydride bomb The uranium hydride bomb was a variant design of the atomic bomb, that was first suggested by Robert Oppenheimer in 1939 and advocated and tested by Edward Teller. It used deuterium, an isotope of hydrogen, as a neutron moderator in a U235-deuterium compound. The chain reaction is a slow nuclear... , fizzle Fizzle (nuclear test) In nuclear weapons, a fizzle occurs when the testing of a nuclear bomb fails to meet its expected yield. The reason for the failure can be linked to improper bomb design, poor construction, or lack of expertise. All countries that have had a nuclear weapons testing program have experienced fizzles...
Badger	18 April 1953	Nevada Test Site	23 kilotons
Simon Upshot-Knothole Simon Upshot-Knothole Simon was a nuclear detonation conducted as part of the U.S. Operation Upshot-Knothole nuclear testing program. Simon was conducted on 25 April 1953 at the Nevada Test Site, and tested the TX-17/24 thermonuclear weapon design which had a yield of 43 kilotons....	25 April 1953	Nevada Test Site	43 kilotons
Encore	8 May, 1953	Nevada Test Site	27 kilotons
Harry Upshot-Knothole Harry Upshot-Knothole Harry was a nuclear weapons test conducted by the United States as part of Operation Upshot-Knothole. It took place on May 19, 1953 in Yucca Flat, in the Nevada Test Site....	19 May 1953	Nevada Test Site	32 kilotons	Extreme contamination of downwinders Downwinders Downwinders refers to individuals and communities who are exposed to radioactive contamination or nuclear fallout from atmospheric or underground nuclear weapons testing, and nuclear accidents...
Grable Upshot-Knothole Grable Upshot-Knothole Grable was a nuclear weapons test conducted by the United States as part of Operation Upshot-Knothole. Detonation of the associated nuclear weapon occurred shortly after its deployment at 8:30am PDT on May 25, 1953, in Area 5 of the Nevada Test Site...	25 May 1953	Nevada Test Site	15 kilotons	nuclear artillery Nuclear artillery Nuclear artillery is a subset of limited-yield tactical nuclear weapons, in particular those weapons that are launched from the ground at battlefield targets... , gun-type fission weapon Gun-type fission weapon Gun-type fission weapons are fission-based nuclear weapons whose design assembles their fissile material into a supercritical mass by the use of the "gun" method: shooting one piece of sub-critical material into another...
Climax	4 June 1953	Nevada Test Site	61 kilotons

External links

• Operation Upshot-Knothole
• Operation Upshot-Knothole - 1953
• Film about Upshot Knothole Tests