On August 24, 1990, hundreds of tourists and residents across the German Baltic coast, including a school group of 40 boys and several teachers, observed and filmed multiple luminous spheres in Y-formation near Greifswald. The event was captured on videotape by independent witnesses and remains unexplained.

Sightings were reported across the coastal corridor from Rostock to the Isle of Usedom. Observers described rapid, non-ballistic accelerations inconsistent with flares, aircraft, or atmospheric phenomena. The timing, days before German reunification, drew particular attention since the area was adjacent to former East German military installations. No German or allied military exercise accounted for the lights.