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
Soviet atomic bomb project CIA. RDS-3 was the third Soviet atomic bomb. On October 18, 1951, the 41.2 kiloton device was detonated - a boosted weapon using a composite construction of levitated plutonium core and a uranium-235 shell. Code named "Joe 3" in the USA, this was the first Soviet air-dropped bomb test. Released at an altitude of 10 km, it detonated 400 meters above the ground. RDS-4 represented a branch of research on small tactical weapons. It was a boosted fission device using plutonium in a "levitated" core design. The first test was an air drop on August 23, 1953, yielding 28 kilotons.