Project 10073 Record: Adak, Alaska Sighting, 11 September 1950

This document details the investigation of a series of photographs taken by a U.S. Coast Guard photographer on 11 September 1950. The photographer, while aboard the U.S. Coast Guard Cutter NORTHWIND in the Bering Sea, captured images of a total solar eclipse. At the time of the event, the photographer reported seeing nothing unusual. It was not until two years later, in July 1952, that the photographer noticed unidentified images on the film negatives while reviewing them. The photographer subsequently submitted the negatives and a report to the U.S. Air Force for analysis under Project Blue Book. The investigation, conducted by the Air Technical Intelligence Center, concluded that the unidentified images were not anomalous objects but rather lens flares. The analysis noted that the 4x5 Speed Graphic camera used for the photography was pointed directly at the sun, and the lens was wide open at f/4.7. The investigators determined that the bright light of the sun, combined with the lack of proportional exposure reduction and the use of a flat glass filter, created the flare spots. They observed that any camera movement caused these spots to shift in the frame, consistent with the behavior of lens flares. The report includes the original observer's questionnaire, correspondence between the U.S. Coast Guard and the Air Force, and the final technical evaluation. The official conclusion reached by the Air Technical Intelligence Center was that the spots were the result of overexposure for sun brightness.