The Vela Incident
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On 22 September 1979, sometime around 3:00am local time, a US Atomic Energy Detection System satellite recorded a pattern of intense flashes in a remote portion of the Indian Ocean. Moments later an unusual, fast-moving ionospheric disturbance was detected by the Arecibo Observatory in Puerto Rico, and at about the same time a distant, muffled thud was overheard by the US Navy's undersea Sound Surveillance System (SOSUS). Evidently something violent and explosive had transpired in the ocean off the southern tip of Africa.
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