IN 1979, a strange ‘double flash’ was observed by a satellite as coming from between South Africa and Antarctica. It was a telltale cue. That kind of flash was usually a nuclear explosion.

Almost 39 years later, there appears to be fresh evidence that’s exactly what it was.

The US ‘Vela’ satellite picked up the flash in the vicinity of the Marion and Price Edward islands in September 1979. That it was an explosion was verified by underwater hydroacoustic listening devices.

Exactly what caused it was has been the subject of ongoing debate ever since.

Was it an exploding meteor? Nobody had owned up to it being a nuclear test …

Speculation abounded at the time that it may have been Israel covertly testing a warhead developed under its secret nuclear weapons program. No evidence was put forward to support this claim.

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But a recent paper published in the journal science & Global Security by the Australian Defence Force Academy’s Christopher Wright and retired Swedish Defence Research Agency investigator Lars-Erik De Geer has reignited the debate.

The thyroid glands of grazing animals concentrate radioactive iodine-131 found in the fallout of nuclear tests. So, samples were regularly collected around the world for testing.

The paper highlights declassified testing of sheep from Western and South Australia shortly after the event. The results found a spike in iodine-131’s distinctive signature among slaughtered animals.

Analysis of weather patterns revealed the nuclear fallout may have been dumped on Australia in rains falling four days after the ‘flash’. Currents among the Indian Ocean jet streams offer a direct link between Australia and the distant, tiny islands..

The researchers say this appearance of iodine-131 just days after the flash and sound of an explosion near Marion Island proves it was a nuclear test.

“Analysts have previously argued that the optical and hydroacoustic signals are definitive indicators for a nuclear test, while the iodine-131 detections provide robust and credible evidence for a nuclear fission event,” they write.

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Bulletin of the Atomic Scientists contributor Leonard Weiss writes in a recently published article: “That study makes it virtually certain that the event was an illegal nuclear test. This strengthens previous analyses concluding that Israel likely carried out a nuclear test in violation of US law and the Limited Test Ban Treaty.”

US President Jimmy Carter was informed immediately that the explosion had been detected.

What came next, however, was confused.

“A panel of scientists carefully selected by the Carter White House produced a report in 1980 that did not rule out a test, but said the probability of its being something other than a test was more likely,” Weiss writes. “That conclusion is now derided by nearly all independent observers who have studied and reported on the issue.”

In 1979, none of the major nuclear nations needed to conduct a clandestine test. And Pakistan, India and South Africa were still a long way off from developing the technology.

That leaves only Israel, Weiss argues.

“Israel was the only country that had the technical ability and policy motivation to carry out such a clandestine test, which, according to some sources, was the last of several and was detected by the Vela satellite because of a sudden change in cloud cover,” he writes.

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