On September 22, 1979 at 12:53am, an American satellite named Vela 6911 recorded a double flash near the Prince Edward Islands in the sub-antarctic Indian Ocean, located between Africa and the Antarctic.
The fact that a double flash could be a sign of a nuclear explosion is what contributed to the theory that a country had carried out a nuclear test there. Many experts said that this was an experiment carried out by Israel in cooperation with the Apartheid regime in South Africa.
Over the years, however, other hypotheses have been raised for the unusual flash, such as a meteor shower. International experts said that had this indeed been an Israeli nuclear test, it would have been a violation of both international and American law.
Former US President Jimmy Carter admitted in his memoirs that American officials at the time had speculated that it was an experiment carried out by Israel and South Africa.
The new research is headed by Christopher Wright of the Australian Defense Force Academy and Lars Erik de Geer, a former member of the Swedish Defence Research Agency.
The two claimed that in October and November of 1979, a few weeks after the Vela 6911 findings, traces of radioactive Iodine (I-131) had been discovered in several dead sheep in Australia.
According to the study, samples from the sheeps’ thyroid glands were sent for tests in the United States, but the test's results were never made public.
In their study, the researchers write that the findings may indicate that the sheep ate some of the grass in the area where nuclear fallout occurred when the September test was conducted.
According to the study, due to stormy weather in the region at the time, the fallout might have been scattered throughout many parts of Australia.
In their study, the researchers also analyze descriptions of an underwater sound wave that was monitored by an American listening station, simultaneously to the occurence of the double flash.
The wave had been talked about in the past, and those who believe that the nuclear experiment indeed took place view it as evidence that reinforces their claim.
Following the findings, a nuclear weapons expert from the US, Leonard Weiss of Stanford University, wrote that the new evidence effectively removes any doubt about the occurrence of the nuclear test.
In the Bulletin of the Atomic Scientists, Weiss emphasized that the circumstantial evidence that the experiment was carried out by Israel keeps growing.
"Israel is the only country that had the technical capability and the political motivation to conduct such a discreet experiment," Weiss wrote. His assertion is based on the assumption that in 1979 none of the major nuclear powers had the need to conduct a secret nuclear test.
Israel's Ambassador to New Zealand Itzhak Gerberg told the local New Zealand Herald newspaper the claims that Israel was the one responsible for the nuclear test "are simply ridiculous.”