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

This document details the investigation conducted by Dr. J. Allen Hynek, scientific consultant to the Air Force, regarding a series of UFO sightings in Dexter and Hillsdale, Michigan, in March 1966. The investigation focused on reports from local citizens, including police officers and college students, who described glowing, pulsating lights of various colors (red, yellow, white, blue-green) hovering near swampy areas. Witnesses reported that the lights moved smoothly, oscillated, and occasionally disappeared and reappeared. Dr. Hynek, assisted by local personnel, interviewed key witnesses and concluded that the sightings were likely the result of 'swamp gas' (marsh gas). He explained that the decomposition of organic material in the swamps produces gases like methane and phosphine, which can spontaneously ignite under specific atmospheric conditions, creating the appearance of glowing, flickering lights. Hynek noted that the witnesses lacked technical training, making it difficult to obtain precise data on angular rates or distances. He emphasized that the sightings were localized to swampy regions and that no evidence of solid craft, propulsion systems, or extraterrestrial technology was found. The report also addresses the intense media scrutiny and public excitement surrounding the events, which Hynek found detrimental to a calm, scientific investigation. He recommended that UFO phenomena be studied as a serious scientific and sociological problem rather than through the lens of sensationalist media coverage.