Philadelphia, PennsylvaniaMarch 1956

On the evening of March 29, 1956, a bright white object with a faint orange tint appeared in the sky over Philadelphia, Pennsylvania during the twilight hours. The witness observed it for roughly two minutes as it moved from northeast to southwest. The object appeared as a solid, sharply outlined shape resembling the star Sirius. It was initially spotted at an elevation of 45 degrees and an azimuth (compass direction) of about 80 degrees, looking roughly south-southwest. As the object moved, it grew smaller and dimmer with distance, suggesting it was moving away from the observer. It eventually climbed steeply and disappeared behind clouds at an elevation of 80 degrees and azimuth of about 10 degrees, indicating a rapid ascent.

The Air Force investigation noted some features consistent with an aircraft sighting, though the documentation suggests uncertainty about the exact nature of the object. Investigators considered the brief duration of the observation and the rapid climb as factors in their analysis. The case file comments indicate the sighting was too short to be a balloon, and while an aircraft explanation was considered feasible based on design, the available evidence remained inconclusive.

The U.S. Air Force concluded this case as unidentified, meaning the object's true nature could not be determined from the available information. The full case file is reproduced below as held by the National Archives across 17 pages of microfilm.