Bedford, MassachusettsJune 1961

On June 14, 1961, a resident of Bedford, Massachusetts reported seeing a bright light in the sky. The object appeared to be roughly the size of the full moon held at arm's length. It was visible for about 50 seconds and traveled across the sky from north to south, moving through an arc from about 360 degrees (due north) to about 45 degrees (northeast).

The light had a distinctive characteristic: it flashed with a regular period of about 4 to 4.5 seconds. The witness reported that the brightness was similar to a full moon at around 20 degrees altitude. The object's elevation angle appeared to remain fairly constant throughout the sighting, suggesting it was maintaining a steady flight path relative to the observer's line of sight.

The Air Force's investigation concluded that the light was probably an anti-collision beacon mounted on an aircraft. The case file notes that the Federal Aviation Agency had authorized some jet airliners to test an experimental anti-collision light consisting of two bright flashes. According to the file, the beacon on a military aircraft flashes approximately 40 to 100 times per minute, which compares favorably with the 4-second period the witness reported. The file also notes that at a distance of 10 nautical miles, an aircraft moving at 150 knots would have an apparent speed consistent with the witness's observations. The intense brightness and the periodic flashing are consistent with viewing such a beacon from that distance, especially with atmospheric effects creating the appearance of varying size and color.

The complete case file is reproduced below as held by the National Archives, spanning 8 pages of microfilm.