Report on the Investigation of the Dexter and Hillsdale, Michigan Sightings of 20-21 March 1966

This document is a comprehensive report by Dr. J. Allen Hynek, scientific consultant to the Air Force, regarding the UFO sightings in Dexter and Hillsdale, Michigan, in March 1966. Hynek conducted a three-day investigation, interviewing numerous witnesses including police officers, college students, and local residents. The report details the consistent observations of reddish-yellow and green lights, often accompanied by a yellow glow, hovering over swampy areas. Hynek concludes that these phenomena are likely 'swamp lights'—a form of low-temperature chemical luminescence caused by the spontaneous ignition of gases like methane, hydrogen sulfide, and phosphine produced by rotting vegetation. He notes that these lights are evanescent, soundless, and match the descriptions provided by the majority of witnesses. Hynek also addresses the 'spectacular' reports of objects, attributing some to the suggestibility of witnesses and others, specifically at Hillsdale, to pranks involving flares. He expresses frustration with the 'amateurish' handling of the press by the Air Force and emphasizes the need for a more scientific and sociological approach to the UFO phenomenon, stressing the importance of high-quality data collection. The report includes various inserts, maps, and news clippings documenting the intense public and media interest in the events.