[ILLEGIBLE], June 1948 - Incident Number: 141June 1948

On June 30, 1948, a man driving on Route 212 between Watertown and Webster in South Dakota observed an unusual object in the sky that remained visible for approximately two hours as he traveled north. The object first appeared as a small, round spot overhead with a polished aluminum color. The witness initially thought it might be an airplane or a bright star, but its complete lack of motion during his early observations ruled out both possibilities.

As the witness continued north and later west, stopping at several points along his route, the object maintained an apparent fixed position in the sky despite his significant change in location. Near the end of his observation period at 1327 (1:27 p.m.), the object suddenly began to break apart. One ball about one-twelfth the size of the original mass dropped from the center, followed by two additional balls of similar size that shot out from the sides and came to an abrupt halt, forming an inverted triangle. Over the next several minutes, the remaining mass broke into hundreds of smaller particles, some leaving faint trails. All the fragments gradually faded from view over approximately nine minutes, with the larger spheres persisting longer than the smaller ones before disappearing as if receding away from the observer.

The witness was a chemical engineer with seven and a half years of amateur astronomy experience. His wife also observed part of the event, and their account of the breakup sequence was nearly identical. A second detailed witness interview on file, though the OCR text is heavily degraded, confirms multiple observations during the same general time period in the same geographic area. The case file includes a checklist form and internal intelligence correspondence routing the report through Coast Guard channels to the Air Force for investigation.

The full case file, 17 pages as held by the National Archives, is reproduced below.