Thule AFB, Greenland, December 1953December 1953

On the night of December 9, 1953, six Air Force pilots and radar operators stationed at Thule Air Base in Greenland reported seeing unidentified objects during training flights over about an hour. The sightings occurred in the same general area south of the base and involved two F-94 jet interceptors.

The first sighting happened at 0912302 (12:32 a.m.). Captain W. W. Irwin, piloting an F-94 at 26,000 feet, and his radar operator, Second Lieutenant R. M. Roberts, spotted a bluish-white, oblong glowing light roughly the size of a half-dollar held at arm's length. The object appeared to have light shining through it, with no tail or exhaust visible. It traveled from south to north at an estimated 1,000 miles per hour, moving straight and level across the sky. The pilots watched it for 2 to 3 seconds before it vanished with no fade-out. Irwin turned to intercept but gained no radar contact.

Four more similar sightings followed in quick succession involving the same two F-94 aircraft. A second crew, Captain D. B. Zook and Second Lieutenant R. H. Zeigler, described a globe of white light with intense brilliance. Other pilots reported a round, glowing white object and flame-like objects that resembled jet afterburner exhaust. In several cases, pilots attempted interception but could not close the distance. One radar operator reported interference similar to ground harmonics (radar noise from surface reflections) when turning toward an object.

The weather at Thule that night was clear with unlimited ceiling and visibility of 10 miles. Winds were light and consistent. The base intelligence officer, Captain Harold R. Miller, coordinated interviews with all six observers and determined they were ordinarily reliable witnesses.

The official evaluation in the case file concludes that all sightings were probably astronomical phenomena, most likely a meteorite shower. The full case file, consisting of 10 pages as held by the National Archives, is reproduced below.