Okinawa, Naha, Kadena, June 1953June 1953

On June 21, 1953, at 1900 hours (7 p.m.), military and civilian observers on Okinawa spotted a small, metallic, spherical object moving across the sky near Naha and Kadena. The sighting lasted about twenty minutes.

Witnesses described the object as ranging in size from a star to a ping pong ball when viewed with the naked eye, but approximately baseball-sized when seen through a theodolite (a precision surveying instrument). It had a silvery or metallic color, produced no sound, left no exhaust trail, and exhibited no unusual maneuvers. Observers at the Ryukyus Weather Service Station in Naha estimated the object's speed at roughly twenty miles per hour, while those using theodolite measurements calculated it at about forty-five miles per hour. The object appeared to travel in a straight line toward the northwest before disappearing into clouds and the approaching twilight at an estimated altitude of about 20,000 feet.

Nine observers participated in the sighting, all either Japanese or Okinawan weather forecasters with six to thirty years of experience. All of them were familiar with jet aircraft and ruled out that possibility. The officers who reviewed the case noted that local F-80 jets were in the area at a lower altitude, but neither their crews reported seeing anything unusual, nor did radar sites record any unidentified tracks. A weather balloon released at approximately 1800 hours (6 p.m.) had drifted eastward, contrary to the object's northwest movement. While the observers appeared sincere and reliable, the fact that no radar detected the object and that winds aloft did not match the object's course made investigators doubt the report's validity.

The full case file, consisting of 30 pages, is reproduced below as held by the National Archives.