Between 1982 and 1986 the Hudson Valley north of New York City produced several thousand reports of the same thing: a very large triangular or boomerang-shaped object with lights along its edge, moving low, slowly and almost silently. The witnesses were suburban residents, police, and staff at the Indian Point nuclear station. Part of the wave is explained and undisputed: a group of amateur pilots from Stormville airfield flew in formation at night with their lights on as a prank, and never denied it. The argument is whether that covers all of it: several reports describe an object blocking hundreds of metres of sky, which is large for a formation of light aircraft.

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Aztec and the Second Crash

In 1948, a year after Roswell, another flying saucer is supposed to have come down at this town in northern New Mexico — thirty metres across, with sixteen bodies inside. The story was told by the writer Frank Scully in a 1950 book, Behind the Flying Saucers, which became a bestseller. Two years later True magazine established that Scully's sources were two confidence men, Silas Newton and Leo GeBauer, who had been selling oilmen an "alien" device for finding deposits. Both were convicted of fraud. Aztec was not put off: from 1998 the town ran an annual UFO symposium, and it became a noticeable source of income for the local library.