Phoenix, ArizonaMay 1952

On the evening of May 1, 1952, near Phoenix, Arizona, a civilian observer spotted an unusual object in the sky at 2200 hours (10 p.m.). The object was moving to the northeast at an altitude of roughly 10,000 feet and climbing at an angle of about 10 degrees. The observer watched it for approximately two seconds before it disappeared from view.

The object gave off an iridescent bluish-green light similar in color to the arc produced by an electric welder. The observer could not determine the object's shape or see any trail or exhaust. No sound was heard. The speed could not be precisely measured, but the observer estimated it exceeded 1,000 miles per hour based on how quickly it moved across the sky.

The Air Force interviewed the witness and gathered the available information into an official report. The observer's reliability was marked as unknown. The sky was clear with visibility of 15 miles or better. Wind conditions were recorded at 260 degrees and 12 knots. The Air Force noted that no meteorological phenomena (weather events) were recorded that could explain the sighting, and no photographs or physical evidence was obtained. No attempt was made at interception or further identification.

The file indicates that the description was similar to a meteor or fire ball, though this appears as a late annotation. The Air Force's formal evaluation of the case was unidentified. The complete case file, comprising 8 pages, is reproduced below as held by the National Archives.