Modesto, CaliforniaSeptember 1953

On September 3, 1953, a newspaper photographer in Modesto, California set up a camera on the roof of the newspaper building after seeing an unusual yellowish-white light near the airport earlier that evening. He left the camera unattended with its shutter open for about four hours. When he developed the film, he found an elliptical-shaped light on the negative that he could not explain, and he called Castle Air Force Base.

The photographer, an ex-Air Force navigator, had originally spotted the light at 7:45 p.m. (1945 PDT) in the direction of Modesto Airport, about ten degrees above the horizon. He and a reporter watched it appear to remain stationary as they drove about a mile east, after which it vanished. They initially thought it was an aircraft on an approach pattern. The camera exposure occurred sometime between 8:20 p.m. on September 3 and 12:15 a.m. on September 4 (2020 to 0015 PDT). The camera, set on an f22 aperture, was mounted about forty feet above street level on the newspaper building's roof, oriented toward the east.

The Air Force investigation noted that Civil Defense ground observers on duty during the exposure period reported seeing what they believed was a small aircraft with its landing light on, flying the traffic pattern at Modesto Airport between 10:15 p.m. and 10:30 p.m. The weather that night was clear with slight haze near the horizon and winds at twelve knots from the southeast. Based on the observers' statements, the alignment of the airport runway relative to the camera, and the presence of aircraft traffic during the exposure window, Air Force officials concluded that the elliptical light was most likely the flash of an aircraft landing light.

The Air Force formally listed the case as unidentified, though the evidence suggested a conventional explanation. The full case file, comprising 23 pages as held by the National Archives, is reproduced below.