What happened
According to a broadsheet printed by the Nuremberg engraver Hans Glaser, at dawn on April 14, 1561, many of the city’s residents witnessed an extraordinary spectacle in the sky. As the sun rose, blood-red arcs appeared, along with red, blue, and black globes, crosses, and long tubes from which more globes emerged. The objects reportedly collided and “fought” with one another for about an hour, then fell toward the ground as if on fire and vanished in smoke. Glaser accompanied the woodcut with a commentary in the spirit of the age: the phenomenon was a sign from God and a call to repentance. The broadsheet is now held by the Zurich Central Library and is among the most frequently reproduced pieces of “evidence” for UFOs in the past.
Witnesses
According to the broadsheet, many residents of Nuremberg, men and women; the only source is Hans Glaser’s print.
Explanations and hypotheses
Most researchers believe the broadsheet describes an elaborate halo display at sunrise – sun dogs, arcs, and light pillars – interpreted as a heavenly sign and depicted in religious terms. Others see it primarily as a symbolic moral message. UFO enthusiasts read the woodcut literally, as a battle between aircraft. No independent accounts from other witnesses survive, which makes the dispute hard to resolve.
Disputed A likely explanation exists, but some of the facts are still disputed.
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