A Sardinian professor's glowing sphere, red flares over the Berlin air corridor, a hovering light watched by B-29 guards in British Columbia, a light that circled an interceptor over Guam and a radar blip beside a B-52 on its record round-the-world flight: five Air Force intelligence reports from 1952 to 1957, published by the Pentagon in October 2026. Officers floated a stalled weather balloon for Guam and a bomber's turn for the radar contact. None of the five was ever identified.