Project 10073 Record: Oak Park Sighting (August or September 1949)

This document contains a Project 10073 record regarding an unidentified object sighting in Oak Park, occurring in August or September 1949. A civilian observer reported an object flying over his house on Watervaleit Avenue at 11-minute intervals. The object was described as bluish-white, flashing, and appearing 'quite high,' with a visual similarity to a 'lightning bug.' The official conclusion for this incident was 'INSUFFICIENT DATA FOR EVALUATION.' The file includes a memorandum dated 27 March 1950 from Lt. Colonel A. J. Hemstreet, Jr., of the Technical Analysis Division, directing that the report be filed with the Performance & Characteristics Branch. Additionally, the document contains a galley proof titled 'The To'lough Rectangles,' which discusses a separate, well-known 1949 sighting by astronomer Clyde Tombaugh in New Mexico. Tombaugh observed a group of geometrically spaced rectangles of light on August 20, 1949, which he later attributed to a natural optical phenomenon, possibly an inversion layer. The document also includes a list of sightings from September 1949, categorizing various reports as meteors, aircraft, or other conventional objects, and a letter from a citizen in Ann Arbor, Michigan, dated 11 January 1950, recounting two personal experiences with strange phenomena, one in 1944 and one on September 1, 1949. The correspondence concludes with an acknowledgment from Colonel Bruno W. Feiling of the Technical Analysis Division, thanking the citizen for their report.