https://foreignpolicy.com/2019/09/22/blast-from-the-past-vela-satellite-israel-nuclear-double-flash-1979-ptbt-south-atlantic-south-africa/ [foreignpolicy.com]
Nuclear proliferation was just one of the Carter administration’s headaches in late 1979. The president was dealing with a slew of foreign-policy dilemmas, including the build-up to what would become the Iran hostage crisis. Carter was also preparing for a reelection campaign in which he had hoped to showcase his foreign-policy successes, from brokering Israeli-Egyptian peace to successful arms control talks with Moscow. The possibility that Israel or South Africa, which had deep clandestine defense ties at the time, had tested a nuclear weapon threatened to tarnish that legacy. And the fact that South Africa’s own nuclear weapons program, which the Carter administration was seeking to stop, was not yet sufficiently advanced to test such a weapon left just one prime suspect: Israel. Leading figures within the administration were therefore keen to bury the story and put forward alternative explanations.