In October 1348, more than a year after the outbreak of the Black Death in Europe, King Philip VI of France asked the doctors of the Faculty of Medicine at the University of Paris to investigate the cause of the terrible plague.
The doctors considered the matter, analyzed the symptoms, examined the evidence carefully, and finally came to their firm conclusion – the cause of the plague is the triple connection of Saturn, Jupiter, and Mars in the 40s of Aquarius which they claimed took place on March 20, 1345. Now that is what I call good science!
In the four years that followed, the plague killed tens of millions more people in Europe and Asia, causing the European population to shrink by about a third of its pre-plague size.
Bonus fact: In late 1979, after a comprehensive worldwide vaccination campaign smallpox – a.k.a the black death – became the first and only disease that humanity has managed to eradicate, so far.