Project 10073 Record Card and Related Correspondence — September 1958

This document collection details a series of radar and visual sightings of unidentified aerial phenomena occurring on September 7, 1958, across multiple radar sites in Montana and South Dakota, including Miles City AFS and Ellsworth AFB. The reports describe radar contacts that appeared to orbit in a relatively small area, with some visual observations noting two objects with green, white, and red flashing lights, appearing the size of a quarter. Intercept attempts were made by military aircraft, but pilots were unable to confirm the objects visually, despite radar contact being maintained by ground stations. The objects were observed to climb and move in circular flight paths, with altitudes ranging from 10,800 to 20,000 feet. The duration of the sightings spanned over three hours. Thirteen photographs of the electronic radar displays were taken, though no physical evidence was recovered. An official evaluation by AFCIN-4E1 concluded that the sightings were likely caused by the same phenomenon, suggesting possibilities such as weather balloons or anomalous propagation and ground reflections. The documentation includes project record cards, teletype messages between military units, and a formal disposition form evaluating the reports.