The Byzantine Empire lasted for more than a thousand years, but in 1453 the capital, Constantinople, was under siege from the Ottoman Turks. The inhabitants believed that their city would fall only when the Moon gave a sign — and in May that year it seemed to come horribly true.
The first omen was when the Moon went into a long and unexpected eclipse. The Byzantine defenders sought divine help with a religious procession, but that was ruined by a tremendous thunderstorm. As a Greek chronicler later wrote: “Such was the unheard of and unprecedented violence of that storm and hail [that it] certainly foreshadowed the imminent loss of all.” The following day, a dense fog enveloped the city, unusual for late spring. And that was followed at night by a fiery light around the dome of Hagia Sophia, the imposing cathedral of Constantinople. By now the citizens were filled with despair and at the end of May the Ottoman Turks finally took the city.
These bizarre meteorological events could be explained, though. In about 1453, the volcano Kuwae in the New Hebrides blew up so violently that massive clouds of dust were shot into the upper atmosphere. According to the American astronomer Kevin Pang, the globe was wrapped in a shroud of volcanic dust that made the Moon look as if it was eclipsed. Sunlight was also weakened and sent the world’s climate plunging.
And the “fire” over the cathedral could have been an intense twilight created by volcanic ash high in the atmosphere reflecting sunlight from below the horizon — similar fire alarms happened after the eruption of Krakatoa.
From the Times