William Shakespeare died on this day 400 years ago. He left behind dozens of plays and sonnets earning him regard as the greatest writer in the English language. English teachers in high schools and colleges worldwide continue to delight and sometimes torture students with the works of Shakespeare as required reading.

“Math and science” kids need not despair. Shakespeare left something for you too, particularly in his plays. He lived during a time when the medieval world of astrology, magic and superstition was being left behind and the Scientific Revolution was beginning.

At the turn of the 17th century, when Shakespeare was most active, astronomy was a very big topic. The publication of De revolutionibus orbium coelestium by Nicolaus Copernicus in 1543 sparked liturgical and public debate about Earth’s place in the universe. After thousands of years of mental gymnastics to describe why planets were observed to stand-still in the night sky yet keep Earth at the center, Copernicus set the world straight with his simple, though uncomfortable for many, sun centered explanation.

The Catholic Church sought to squelch the Copernican revolution when it placed the book on its Index of Banned Books the year of Shakespeare’s death. It stayed there for over 200 years alongside similar works by Johannes Kepler which also reasoned the sun at the center of our solar system.

This new worldview clearly influenced his writings. Shakespeare’s plays reflect the talk of the time with rich astronomical references. Thomas Digges, who published the first English account of this new view of astronomy, may have been an influence. Shakespeare, who was twelve at the time, lived three blocks from the Digges family in North London.

A search of the complete works of Shakespeare finds over 100 references to “stars."

In Act five, scene 1, Hamlet declares, “He whose grief … conjures the wandering stars, and makes them stand like wonder-wounded hearers?” Here he is referencing retrograde motion of the planets, central to the debate over whether it was the sun or Earth at the center. Retrograde motion is an illusion created as Earth passes slower moving outer planets such as Mars or Jupiter in their orbits. The planets appear to move backwards.

Throughout May and June, Mars continues its journey toward the constellation Libra. As June turns to July Mars will appear to stand still before apparently moving backwards through Scorpius, Sagittarius and finally Capricornus in June 2018 where the whole cycle starts over again.

Shakespeare also made reference to the 44 B.C. comet purportedly seen following the death of Julius Caesar in his play of the same name. Some have said that Shakespeare was inspired to include comets in Julius Caesar and History of Henry VI, Part I by a sighting of Halley’s comet during his lifetime. This is unlikely as these plays were written about 10 years before sighting of Halley’s comet in 1607.

There have been numerous books written about science’s influence on Shakespeare. I’ve enjoyed "The Science of Shakespeare: a New Look at the Playwright's Universe" by Dan Falk. No need to rush to amazon.com, WorldCat shows it on the shelf at NC State, UNC Chapel Hill, and Duke University libraries. Durham County libraries also holds two copies.

There’s more than science there, too. Our own Greg Fishel delights in Shakespeare’s puns. For example, Claudius asks Hamlet, "How is it that the clouds still hang over you?" Hamlet, who is mourning his father responds: "Not so, my lord, I am too much in the sun." Get it?