Halley's Comet Alarms Europe

1531

A bright comet trailed across the European sky for weeks, observed and measured by the German astronomer Peter Apian, whose careful notes would later help Edmond Halley calculate its orbit. Preachers insisted it foretold war. In much of Europe, they were, as always, correct. Apian's observation that the comet's tail pointed away from the Sun was one of the earliest empirical contributions to cometary science.