Correspondence regarding 9 May 1964 UFO Sighting in Chicago, Illinois

This collection of documents details the investigation of a UFO sighting reported by a civilian in Chicago, Illinois, on May 9, 1964. The witness, an amateur astronomer, reported observing three large, light-green crescent-shaped objects traveling at high speed from east to west, south of the constellation Leo, for approximately three seconds. The witness provided a detailed account, including a sketch, and noted that the objects held a tight formation and exhibited an oscillating or pulsing motion. The witness emphasized that the experience was vivid and fear-inspiring, noting that he was trembling and perspiring afterward. He immediately contacted the Chicago Tribune, the Adler Planetarium, and Sky & Telescope magazine to report the event. The report was eventually forwarded to the Foreign Technology Division of the U.S. Air Force and subsequently to Dr. J. Allen Hynek, an Air Force consultant for Project Blue Book, for evaluation due to the astronomical nature of the report. Dr. Hynek engaged in extensive correspondence with the witness. Initially, Dr. Hynek proposed that the sighting was a subjective experience, specifically an after-image caused by the witness looking at a red light on his telescope dials before looking up into the night sky. The witness, who described himself as a cynic regarding myths and superstitions, cooperated fully with the investigation and even suggested the red light theory himself. However, the witness remained troubled by the 'eerie oscillating' motion of the objects, which he maintained was the most significant aspect of the sighting. Dr. Hynek eventually suggested that the oscillating motion might have been caused by light reflected from the bottoms of birds illuminated by distant mercury street lights, though he admitted this was speculative. Ultimately, Dr. Hynek concluded that the sighting was likely a subjective experience and recommended closing the case on that note, praising the witness for his honesty and cooperation.