South-Central Alaska, November 1950November 1950

On the evening of November 20, 1950, in South-Central Alaska, witnesses across a vast region saw a brilliant blue-white flash light up the sky like daylight for just a few seconds around 7:50 p.m. The sighting was reported from locations over 185 miles apart, including Anchorage, Kodiak, and as far north as Healy. Shortly after the flash, observers in some areas heard a series of explosions that rumbled across the sky at intervals.

One of the most detailed accounts came from a civilian living about four miles south of Anchorage. He reported seeing the blue-white object traveling northwest and low across the sky from the southeast. About thirty seconds after the initial flash, he heard an explosion directly overhead, followed by four more explosions in rapid succession, each growing fainter and more distant. The observer emphasized that the entire sequence happened almost directly above his location, a little to the south. Weather officials and Civil Aeronautics Administration personnel also confirmed the bright blue flash and the accompanying rumbling sound.

The Air Force's investigation drew on reports from weather stations, military and civilian observers, and even a seismograph at the University of Alaska. The official weather bureau log at Merrill Field in Anchorage described "a bright blue flash accompanied by a loud rumbling like thunder" that swept across the sky. An engineer with the Civil Aeronautics Administration noted the phenomenon came from a southeasterly direction and lasted about two to three seconds, followed by a sequence of rolling sounds that he initially thought might be caused by Air Force maneuvers.

The seismograph at the University of Alaska recorded no disturbance, and radar operators detected no objects on their screens. Military air traffic controllers and pilots in the area were interviewed, along with dozens of civilian witnesses. Descriptions of the object and the direction of travel varied somewhat, though most observers agreed on the blue-white color and the explosive sounds that followed.

The Air Force's official conclusion, stated in the final intelligence report, was that the phenomenon was almost certainly a meteor or meteoroid passing through Earth's upper atmosphere. When such objects encounter the atmosphere at high speed, they become heated to the point of glowing brightly before breaking apart. The multiple explosions heard by witnesses would be consistent with a large meteor fragmenting as it descended. Weather conditions at the time, with scattered clouds at 3,000 and 5,500 feet and ten-mile visibility, allowed the bright flash to be seen over a wide area. The full case file, consisting of 14 pages as held by the National Archives, is reproduced below.