Nuclear weapons tests in Australia known at the time as Christmas Island (not to be confused with Christmas Island in the Indian Ocean) between 1957 and 1958. These were airbursts mostly occurring over water or suspended a few hundred metres above the ground by balloon. In Australia there were three sites. Testing was carried out between 1952 and 1957 and was mostly done at the surface. A few hundred smaller scale tests were conducted at both Emu Field and Maralinga between 1953 and 1963. Two separate atomic test projects occurred at the islands, the first being Operation Hurricane and the second being Operation Mosaic The
Operation Upshot–Knothole 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 Rock V in conjunction with the "Grable" shot. "Grable" was a 280mm shell fired from the "Atomic Cannon" and was viewed by a number of high-ranking military officials. The test series was notable as containing the first time an atomic artillery shell was fired (shot "Grable"), the first two shots (both fizzles) by University of California Radiation Laboratory—Livermore (now Lawrence Livermore National