Newly discovered data from radioactive sheep provides strong evidence that a mysterious “double flash” detected almost 39 years ago near a remote island group was a nuclear explosion.
Ever since the flash was observed by a US Vela satellite orbiting above Earth in September 1979, there’s been speculation that it was produced by a nuclear weapon test by Israel. International researchers in the journal Science & Global Security analyzed previously unpublished results of radiation testing at a US lab of thyroid organs from sheep in southeastern Australia in order to make their determination.
The flash was located in the area of Marion and Prince Edward islands, which are in the South Indian Ocean about halfway between Africa and Antarctica.
“A new publication sheds further light on the Vela Incident of 1979,” said Professor Nick Wilson of Otago University at Wellington, who highlighted the findings but was not involved with the study itself. “[The research] adds to the evidence base that this was an illegal nuclear weapons test, very likely to have been conducted by Israel with assistance from the apartheid regime in South Africa.”
Wilson, an epidemiologist and member of the Australia-based Medical Association for the Prevention of War, said the test would have violated the Limited Test Ban Treaty signed in 1963, and urged the United Nations to mount a full inquiry.
The researchers conclude that iodine-131, which is an unstable radioactive form of the element iodine found in the thyroids of some Australian sheep, “would be consistent with them having grazed in the path of a potential radioactive fallout plume from a [Sept. 22, 1979] low-yield nuclear test in the Southern Indian Ocean.”
Thyroid samples from sheep killed in Melbourne were regularly sent to the US for testing — monthly in 1979 but also in the 1950s and 1980s, researchers say.
According to a report in the New Zealand Herald, the sheep had been grazing in an area hit by rain four days after the flash incident was observed, which would have been in the downwind path from the suspected explosion site.
Researchers also said the detection of a “hydroacoustic signal” from underwater listening devices at the time is another piece of evidence pointing to a nuclear test.
Israel, which has neither confirmed nor denied the existence of a nuclear program, dismissed the claim that it was responsible for the 1979 incident.
Israel’s ambassador to New Zealand, Itzhak Gerberg, told the Herald, when asked if Israel was responsible for the explosion: “Simply a ridiculous assumption that does not hold water.”
However, the country’s former Knesset speaker, Avrum Burg, told a conference in 2013 that “Israel has nuclear and chemical weapons” and called for public discussion.
Commenting on the findings, US nuclear weapons expert Leonard Weiss of Stanford University said in the online Bulletin of the Atomic Scientists that the “important” new evidence “removes virtually all doubt” that the flash was a small-yield nuclear explosion.
Weiss added that there was “growing circumstantial evidence” that it was conducted by Israel.
“Israel was the only country that had the technical ability and policy motivation to carry out such a clandestine test,” he said.