Shiroi Air Base, Japan, November 1957November 1957

# Shiroi Air Base Sighting, November 1957

On the evening of November 7, 1957, military and civilian personnel at Shiroi Air Base in central Japan observed a starlike object moving steadily to the west over a two-hour period. The object was visible from the southwest and remained bright throughout the observation. Multiple witnesses, including both U.S. Air Force staff and Japanese nationals employed at the base, reported seeing the phenomenon during this extended timeframe.

The sighting occurred during evening hours with clear skies. Witnesses described the object's movement as steady and sustained, with the object maintaining visibility from a southwestern direction relative to the base. The extended observation period allowed multiple personnel to view the object and record details about its behavior and apparent motion.

The Air Force's official investigation included interviews with 14 individuals connected to the sighting, 12 of whom were U.S. Air Force personnel and two of whom were Japanese nationals. Three additional Japanese civilian employees at the base were identified as having information about the sightings but were initially unavailable for interview due to illness. The investigation gathered weather observations from Haneda Air Base in Tokyo, since Shiroi Air Base had no weather station of its own.

The Air Force concluded that the object was probably a balloon (a weather balloon used to measure atmospheric conditions). The case file notes that Venus was in the position where observers reported seeing the object, suggesting that misidentification of the planet may have contributed to the sighting reports.

The full case file is reproduced below as held by the National Archives, 104 pages in total.