Los Alamos, New MexicoJune 1949

On the evening of June 20, 1949, a security inspector at Los Alamos, New Mexico was standing outdoors near the center of the mesa when a bright light caught his attention. The time was 2010 (8:10 p.m.) local time. He watched as a round object traveled from west to east, passing directly through the zenith, or point directly overhead. The object was blue-green in color and turned to orange-red just before it vanished. The entire sighting lasted only three seconds. The observer reported that the object was not moving particularly fast, and it made no sound. It simply disappeared as though it had been switched off.

The investigator noted that weather conditions were good at the time of the sighting. The observer, whose background had been checked as part of his employment with the Armed Forces Special Weapons Project (a nuclear weapons facility), met all requirements for his security position. The Air Force collected information about the sighting in June 1949 but appears to have made no determination about the object's nature based on what survives in this file. The case was initially recorded as unidentified, though one section of the paperwork notes "Astro (METEOR)" as a possible explanation, suggesting that someone considered a meteor or astronomical phenomenon as a potential cause.

The file contains 10 pages of forms and administrative notes held by the National Archives as part of Project Blue Book's official records.