Larson AFB, Moses Lake, WashingtonJanuary 1953

On January 28, 1953, approximately 60 military and civilian personnel at Larson Air Force Base near Moses Lake, Washington observed an unidentified flying object. The sighting began at 0715 (7:15 a.m.) and lasted only about five minutes. Witnesses described the object as circular and green in color, resembling a large weather balloon. The object moved in a generally southwesterly direction while bobbing vertically and drifting sideways. No sound was reported.

The investigation quickly turned to ruling out conventional explanations. The Air Force checked radar sites in the surrounding area and found no unusual returns or activity. No weather balloons had been launched from Larson during the reporting period. Notably, wind data collected from nearby weather stations showed winds blowing from the northeast at various altitudes. This meant the object was moving against the prevailing winds, making a balloon explanation difficult to support. All observers reported seeing the object just below the cloud layer, which sat at roughly 12,000 feet.

A fighter aircraft was scrambled to intercept. Two aircraft became airborne at 0743 (7:43 a.m.) and conducted a thirty-minute search of the area but found no trace of the object. No civilian or military air traffic had been reported in the vicinity at the time of the sighting, and no photographs were taken.

The Air Force's formal conclusion, as recorded in the case file, was "Unknown." The complete case file, consisting of 7 pages as held by the National Archives, is reproduced below.