Between 1956 and 1963, the United Kingdom conducted seven nuclear tests at the Maralinga site in South Australia, part of the Woomera Prohibited Area about north west of Adelaide. Two major test series were conducted: Operation Buffalo in 1956 and Operation Antler the following year. Approximate weapon yields ranged from . The Maralinga site was also used for minor trials, tests of nuclear weapons components not involving nuclear explosions. Kittens were trials of neutron initiators; Rats and Tims measured how the fissile core of a nuclear weapon was compressed by the high explosive shock wave; and Vixens investigated the effects of fire or non-nuclear explosions on atomic weapons. The minor trials, numbering around 550, ultimately generated far more contamination than the major tests. Operation Buffalo consisted of four tests; One Tree () and Breakaway () were detonated on towers, Marcoo () at ground level, and the Kite () was released by a Royal Air Force (RAF) Vickers Valiant bomber from a height of . This was the first drop of a British nuclear weapon from an aircraft. Operation Antler in 1957 tested new, light-weight nuclear weapons. Three tests were conducted in this series: Tadje (), Biak () and Taranak (). The first two were conducted from towers, while the last was suspended from balloons. Tadje used cobalt pellets as a tracer for determining yield, resulting in rumours that Britain was developing a cobalt bomb. The site was left contaminated with radioactive waste, and an initial cleanup was attempted in 1967. The McClelland Royal Commission, an examination of the effects of the minor trials and major tests, delivered its report in 1985, and found that significant radiation hazards still existed at many of the Maralinga sites. It recommended another cleanup, which was completed in 2000 at a cost of AUD $108 million (equivalent to $ in ). Debate continued over the safety of the site and the long-term health effects on the traditional Aboriginal custodians of the land and former personnel. In 1994, the Australian Government paid compensation amounting to $13.5 million (equivalent to $ in ) to the traditional owners, the Maralinga Tjarutja people. The last part of the land remaining in the Woomera Prohibited Area was returned to free access in 2014. By the late 1970s there was a marked change in how the Australian media covered the British nuclear tests. Some journalists investigated the subject and political scrutiny